Sunday, June 26, 2011

The Worst Cars in the World

Volumes could be filled on this subject. Everyone probably has their own opinion as well. The likelihood of finding 50 different opinions on this subject by talking to 50 different people is very high. Occasionally I will write about a car that is part of my never ending list of the worst cars that were sold as new during my lifetime. These might not be the worst cars ever since they are only cars that have been sold in the last, I won’t say how many years, but anything that was made before I was born doesn’t count.

Some of you will see something on my list that you owned at some point in the past and perhaps even liked. If you disagree with me, that’s too bad, you are wrong. Don’t worry, it’s not personal. You can find a website or two dedicated to each one of the bad cars on my list with people posting all sorts of nonsense about how great their car is. Just because a lot of people like something doesn’t mean that it’s good. I would even say that many people are fans of one car or another just because it is so crazy bad.

So let’s start with the following, and as you see articles on these bad cars remember that they are listed in no particular order:

Volkswagen Bus/Beetle

Might as well start out with the car that might be the most controversial of all of the vehicles on my list. The original bug was commissioned by Adolf Hitler. How in the world could anything that came from that man’s mind be good? The designer of the VW beetle was Ferdinand Porsche but he cannot be blamed for how awful the Beetle turned out. If you were under pressure from Hitler to design something small, cheap, and something that would keep the people of the Third Reich humble, you would probably come up with the same thing. The people would have never had a chance of rising up against the Fuhrer with such bad cars to drive. Porsche redeemed himself in the following years with some really fantastic cars.
Sorry Herbie but you are a terrible car.
The Beetle was produced from 1938 to 2003 and over 21 million units were rolled off the assembly line. Sales of the original Beetle ceased in the U.S. after 1979. This car is often chosen as one of the most influential cars of the 20th century but so what, this does not make it a good car. Cigarettes are also very popular and influential but that shouldn’t give them a special place in anybody’s heart.

The bus was produced from 1950 to the present, but the old air-cooled models disappeared from showrooms in the U.S. in 1980. I am referring to the T2 transporter here, the one that was beloved by the hippies of the 60’s. The T2 is still in production in South America. In the U.S. market the T2 was replaced by the Vanagon which was a much better vehicle, and that was later replaced by the Transporter which was even better.

The reason these things are so bad is the same reason that so many other cars are bad. They are terrible to drive, they have no power, and they sound funny running down the street. Climbing a mountain pass with an underpowered air cooled engine is never good. Every single one leaks oil and there is not much you can do about it. Most of the early Beetles and Buses didn’t even have an oil filter. That’s really good for making the engine last a long time.

These vehicles had air cooled engines which means that they didn’t have a radiator or antifreeze circulating through the engine. If you want to find out whether or not your local auto parts store employs reasonably knowledgeable people behind the counter, call them up and ask them if they have an upper radiator hose for a 1977 VW Bug. If they actually try to look up the part, then you know that’s not the person you want helping you.
This 1977 bug looks almost exactly like a 1947 bug. Obviously
developing the product over time wasn't that important to VW.
The old bugs and buses had a big fan on top of the engine that would constantly blow air down around the engine to keep it cool. This is similar to the way your lawnmower engine stays cool except your lawnmower is small enough that it doesn’t need a fan. This fan was also the fan that would move the air up to the front of the vehicle for the heater and defrost. The heater and defrost are so bad that you have to always keep a towel on the passenger seat so you can wipe the inside of the windshield in order to avoid dying in a wreck, and the rest of the time you are just plain freezing from the lack of heat in the passenger area. If you drove the vehicle on a long trip then you could possibly get enough warm air from the back that you might be able to travel without freezing.

The bus is probably slightly worse then the bug just because it’s bigger, but whatever, neither one is practical. Perhaps the only reason that anyone ever bought either one is because they lived in a third world country and that’s all there was, or they lived in a country where the bug was the only thing that got good gas mileage. How can a car that uses the air pressure in the spare tire to power the washer fluid sprayer, be considered a good car.
Can you imagine hauling your kids around in this. My parents
actually had a few of these before I was born. I'm pretty sure
they were hippies. 

Many of you are thinking that these old V-dubs are so cute and nostalgic that it seems highly inappropriate to criticize them. Think about what it would be like to have one of these things as your daily driver today. You would hate it. Just for the sake of comparison, think of what it would be like to have something else that was sold at the same time as one of these Volkswagens, as your daily driver today. You might still hate it but probably not as much, unless it was one of the other bad cars that you might find on my list.

If you like them because they are old, that’s fine, if you like them because they are quirky, that’s okay too, but to think that anyone ever drove one of these things as their daily driver is almost laughable. The hippies that used to run around in the buses extolling peace, love, and being good to nature were spewing so much air pollution that their ignorance really shined through.

Many people say they were well built, but when compared to the likes of a Chevy Vega, or an AMC Gremlin of course they would seem well built. Some of the appeal came from the relatively good fuel economy that they achieved. They typically got about 30 miles per gallon from an engine that was only good for about 30 to 60 HP. Along with this they had a top speed that wouldn’t let them keep up with traffic on the freeway. This does not make them efficient by any means.
The custom Baja Bug, yuck!
The Volkswagen beetle and bus were toys, not cars. As cars they were terrible and if you have ever had one then you may know exactly what I am talking about. If you had one in the past and you disagree with me now, then let me ask you this question. Would you make this car your commuter today if somebody offered you one that was in mint condition?

Friday, June 24, 2011

AWD v. 4WD

If all the wheels are pushing, what’s the difference?
When the SUV craze first began back in the mid 90’s, nearly every single new SUV offering, from every manufacturer, had four-wheel-drive (4WD). As customer preferences have evolved, which they can do very very quickly. That 4WD option that nearly everything was equipped with has changed to what might be more accurately called all-wheel-drive (AWD).
AWD and 4WD seem like they are the same thing because vehicles that are equipped with either have the ability to allow all 4 wheels to propel the vehicle down the road. This is true, they are pretty much the same, but there are some fundamental differences that make them what they are, and in the end these differences make them very different. One thing that seems certain is that the term 4WD seems to be applied to things that are more truck like, and AWD seems to be applied to things that are more car like. This is one difference but let’s get into this a little deeper.
Typical FWD layout
The drivetrain of the vehicle is the part, or system of parts, that make up all of the rotating assemblies that come inline after the engine. This includes the transmission, the driveshafts, the axles and axle shafts, and the wheels. All of these parts can be laid out in different ways but every vehicle will usually have all of these drivetrain parts somewhere in the system. The drivetrain and the engine together are usually referred to as the powertrain. Front-wheel-drive (FWD) vehicles have a more compact drivetrain with everything essentially located under the hood, or in or near the engine compartment. Small vehicles usually have this kind of drivetrain layout. Rear-wheel-drive (RWD) vehicles have a different layout that supplies the rotational power to the rear wheels. This has all of the same drivetrain components as a vehicle with FWD except it will also have a driveshaft that will come out of the back of the transmission to send power back to the rear wheels. This kind of setup is always found on pickup trucks and on many larger cars.
Typical RWD layout.
The trucks, SUVs, and a few cars that are equipped with 4WD have a drivetrain layout that is pretty much like a RWD vehicle but there are a bunch of extra things thrown in. Instead of a driveshaft being attached to the back of the transmission, another box of gears known as the transfer case is there between the driveshaft and the transmission. The transfer case is responsible for taking some of the torque that is going to the rear wheels and turning that rotation around to send it to the front wheels.

The transfer case usually has several different modes under which it can operate. Some of the more familiar ones include 2 high, 4 high, 4 low, and in many cases Neutral. 2 high is the mode that you would drive in when roads are good and extra traction is not required. This is kind of like the normal mode of operation.
4 high will shift the transfer case to direct power to the front wheels and the rear wheels equally. In 4 high the driveshaft to the front wheels and the driveshaft to the rear wheels will turn with an equal amount of force and speed. This is the reason that the wheels of a 4WD vehicle seems to hop or bind when the vehicle makes a sharp turn on pavement or hard ground while in 4 high. This mode provides the high traction necessary to maintain control in snow or mud loose dirt.
Most 4WD and some AWD systems
will be laid out like this.
4 low is like 4 high in that power is directed to the front wheels and the rear wheels equally, except now the torque is multiplied through a final, super low gear reduction. This means that the engine will turn very quickly but the wheels will turn very slowly, in all of the gears. This torque multiplication is used to sacrifice speed for more of the raw twisting force that is torque. This helps a big heavy truck climb straight up a very steep hill with minimal effort. The trade off is that while the truck can now climb the hill that it couldn’t climb in 4 high, it won’t climb very quickly. 4 low is all about maximum torque along with maximum traction.
The last mode is neutral. This disengages the output of the transmission from the output of the transfer case. This is pretty much what neutral in the transmission does; it’s just another way to do it. Some 4WD vehicles do not have neutral in the transfer case; they only have it in the transmission. When towing a truck or SUV with a tow rope, it is better to put the transfer case into neutral than to put the transmission into neutral while towing.
All of these different modes of 4WD are usually selected manually as needed. This is why sometimes 4WD is referred to as part-time 4WD. Many newer vehicles with 4WD will have some auto selection capabilities in the transfer case as well. These vehicles might have a transfer case selection that is referred to as AWD or auto 4WD. In this mode the transfer case uses computer controls to look for slippage between the front and rear wheels. If the computer sees any of this slippage it will automatically shift the transfer case from 2 high, to a mode that is essentially AWD.
So then what exactly makes this auto mode AWD and not 4 high? When the vehicle is running with AWD, the transfer case is splitting power between the front and rear wheels, but the 2 drive shafts, meaning the front and rear driveshafts, are not locked together. They are allowed to turn at different speeds if needed.
Any transfer case capable of running in this kind of AWD mode contains what is called a differential. This is the set of gears that allows the front and read driveshafts to turn at different speeds. The differential allows a rotational speed differentiation to occur when needed. The time that this is needed is usually while the vehicle is turning. Remember the SUV in 4 high, and how the wheels bind and skip when turning? This is because there is nothing in the transfer case to allow one driveshaft to turn at a different speed from the other while the vehicle is going around a corner. Every drive axle on the vehicle will also have differential located between the drive axles that turn each wheel. This allows the outside wheel to turn faster when going around a corner than the inside wheel.
Because of this center differential, AWD is not as effective in extremely low traction situations as 4 high. This is because if the front or rear axle has no traction whatsoever and the wheels are slipping, the differential will actually take all of the torque from the wheels or axle that does have traction. The slipping wheels literally take all the power from the non-slipping wheels and the vehicle quits moving. This happens because of the way the differential works. It must allow for faster rotation of one wheel or axle if that’s what that wheel or axle what’s to do. On normal dry pavement the wheel spinning faster is allowed to do so in order to go smoothly around corners, so in low traction situations the wheel that wants to spin faster (the one with no traction that is spinning on the ice) is allowed to spin as fast as it can. Many AWD and 4WD vehicles will have some kind of mechanical or electromechanical device that will prevent this from getting out of control to the point where you are totally stuck. If your vehicle doesn’t have this kind of torque limiting device then it is very frustrating to get stuck and see just one wheel spinning, even if you have 4WD or AWD.
In Plain English
So let’s sum it all up. AWD has a center differential and 4WD does not. AWD usually requires no action on the part of the driver to make all 4 wheels turn, and 4WD usually does require the pull of a lever or the push of a button in order to engage. AWD works well for all driving situations, and 4WD is only for low traction situations. AWD vehicles almost never have a low range, and 4WD vehicles almost always do have a low range. AWD is good in snow, a little mud, and gravel, 4WD is better in each of these situations and will also climb steep hills, as well as go down steep hills and remain in perfect control (most of the time).
Nearly all 4WD vehicles have the exact same drivetrain layout, but when it comes to AWD the layout has many variations. Many AWD vehicles will have a drivetrain layout that is essentially the same as any FWD vehicle. This is because they usually run around with only the front wheels moving the vehicle down the road. They will of course have a driveshaft coming out of some sort of transfer case that goes to the rear wheels, but this rear driveshaft, and the rear wheels will only engage when the front wheels slip. This is the type of AWD system that you typically find on all of the cross over type vehicles that are on the road today. Cars such as the Chevy Equinox, Ford Escape, Honda CRV, and Toyota RAV4 fall into this category. Sometimes you will see some kind of emblem that says 4WD on the back of a vehicle with this type of FWD bias AWD system. Don’t be fooled, they do not have true 4WD.
Which One Should I Buy
AWD cannot compete with something like this SUV
with 4WD.
If you want good traction in the snow then get AWD. If you want good traction in the snow but spend a fair amount of time off-road then get 4WD. If you want to drive something more like a normal car then get AWD. Trucks with 4WD will require a bit more maintenance, are usually heavier, and usually don’t have as much interior space. 4WD is also more complex and costs more to make. Trucks with AWD are usually not really that great off-road, and cannot come close to getting to the places that 4WD go. Because most people are not into climbing steep mountains and slogging through deep mud, they usually go for the AWD. That is why today’s SUVs usually have AWD and not 4WD.

Wednesday, June 22, 2011

Driving Ruminations, Chrysler 200

It's go time for the smallest of the Big Three, will Chrysler come through?
Sales are up, and the corporation is now in good hands. This is what the people at Chrysler would have the general public believe. Perhaps this is true, but who are the people at Chrysler now anyway? We still see cars and trucks with the Chrysler, Dodge, and Jeep names on the tailgate, trunk lid or grill, but who is it now that is building these cars. That’s a good question since the company has traded hands a few times in recent history, and now we ask the question: are the current chieftains of the Chrysler Corporation putting anything new out there that’s worthwhile?
Back in 1998 Daimler Benz, the people that build Mercedes, essentially bought out Chrysler and joined the companies together as two separate companies that were tied together so that two equal companies could market automobiles all over the world appealing to a wider audience of potential buyers than what they could appeal to individually.
Daimler could not make a go with Chrysler as an asset so the anchor was thrown over board in 2007. Chrysler was purchased by Cerberus Capital Management who tried to get things going but failed due to the latest recession and the essential crash of the US auto industry in 2008. As Chrysler emerged from chapter 11 bankruptcy in 2009 they were bought out by the Fiat S.p.A. of Turin, Italy. Fiat now owns about 54% of Chrysler which is enough to call the shots. Their stake may go as high 70% at some point. This means that Fiat will be able to use Chrysler to help them make their way back into the U.S. market.
With all of the problems that Chrysler has had they have not been able to spend much money developing new models and redesigning old ones, but with their problems hopefully behind them, and with Fiat firmly in control, they are now rolling out several new models and redesigned models to the public here in the U.S. According to Fiat they will also be able to start selling several of these new models in Europe under the Fiat and Lancia name plates.
The hope is that these recently released cars and trucks can renew Chrysler’s product line in a way that will excite the auto buying public. With new logos and new sheet metal, these models really need to be successful in order to help Fiat get the Chrysler group going strong again. One of these models that I recently had a chance to drive for a few days was the new 2011 Chrysler 200.

I had this car for three days recently while spending some time in Cleveland, Ohio. I was there on business but had a few moments here and there to spend some time in the Cuyahoga Valley National Park. This is an area of thick forests and rolling hills, and an excellent place to test a car such as this one. This was also a good place to do some hiking and take few pictures.

The Cuyahoga Valley National Park is located along the Cuyahoga River between Cleveland and Akron. The park is a mix of forested scenery, walking trails, creeks, rivers, waterfalls, and some interesting history. It’s not a park on the scale of Yellowstone or the Grand Canyon, and it is not as unique as the National Parks of the Western U.S. but it’s still a very nice place to visit if you find yourself staying somewhere in the suburbs of Cleveland and Akron. It’s also a great place to test drive a car.
The 200 that I was driving was the touring edition. Nicely equipped with such things as the new 3.6 liter Pentastar V6, good for 283 horsepower, and an EPA projected fuel economy rating of 19 city, 29 highway. I probably put about 200 miles on the car and I would say that the fuel economy ratings are probably accurate. The horsepower rating sounds accurate as well.

This engine had to be the best V6 engine that I have ever experienced in a Chrysler product. Long gone are the old buzzy sewing machine like mills that used to be so common in Chrysler sedans. While Chrysler has been building engines around modern over-head cam architecture for some time they have struggled to nail down a design that could be versatile enough to be used in many different vehicle platforms. This is something that has cost the company a tremendous amount og money. Most companies can save money by using the same engine in multiple models but changing the tuning or the computer programming slightly to make the engine most effective in the given platform. The Pentastar found in the 200 is slated to be tuned for use in everything from sedans, to sports cars, to SUVs. This engine shows some real potential especially if it proves to be as reliable as some of the V6 engines used by the midsize sedan sales leaders. 

While not perfect the engine felt very nice and had plenty of power down low, but felt a bit weezy on the high end. Throttle response also lacked a smooth linear feel and the vehicle always seemed to want to leap off the line in a way that is not very becoming of a sedan such as this one. Leaping off the line is never a problem, but application of power ought to feel smooth and follow a predictable line rather than feeling as if a switch is just being turned on and off. Some of these issues might simply be a matter of tuning rather than a problem with the way the engine itself functions.
The six speed transmission is the nicest ever in a midsize Chrysler sedan, and it’s about time they got rid of the old 4 speeds that they kept for so many years. To think that there was a time when all automatics only had three speeds seems strange now with 6 speeds being the new standard. The autostick function worked well while driving up and down the hills of the Cuyahoga Valley National Park. When traveling down a hill one must ride the brakes too much because the current gear never seemed to want to keep the vehicle speed in check. The transmission had to be manually downshifted multiple gears in order to keep from riding the brakes. The engine just seems to want to rev higher and higher and the vehicle doesn’t slow down without multiple downshifts. Some kind of grade logic control within the transmission programming would be really good when driving in hilly country such as where I was driving.

Brandywine Falls in the Cuyahoga Valley National Park.

Overall the styling of the interior and exterior is much improved over the old Sebring sedan that the 200 replaces. This new design appears much more upscale and doesn’t look as cheap as the old vehicle. This is an area where Chrysler has made massive improvements in the last few years.
Chrysler has had several models in the past that looked good from a distance but when you got close to them, the fit and finish was so poor that the plastic in the dash looked like it was formed in some kind of cheap blow molding process. You might say that Chrysler cars and trucks looked good from far, but far from good. The interiors on the upscale models looked just as cheap as the interiors on the entry-level models.
The 200 is flex fuel and will run on ethanol, assuming you even know where a place is that sells the stuff.

The interior in the 200 is really nice. Soft-touch plastics and chrome bits abound in the passenger cabin. The design looks good and has some nice details that give it a bit of flashy style. The buttons feel firm and connected rather than cheap and hollow. The gauges are easy to read and the overall ergonomics are well thought out.
The only problem with the exterior is that it still looks somewhat like the Sebring and this is probably because some of the chassis parts are the same. This kind of thing happens when designers are working with a limited budget. Some of the other new models and redesigned models from Chrysler show the same kind of thing. Because of the new powertrain and due to the fact that the exterior and interior are different enough from the Sebring, I don’t think any similarities between the new and the old matter much. The 200 is a nice looking car.
An old service gargae in the historic village of Boston Mills, OH.

Will this car help to really get Chrysler back on its feet? Maybe, but I think it’s more of a good first step towards recovery. With further development the potential is there for great things. The 200 is much better than the old Sebring but considering the competition, Chrysler may struggle to keep this car fresh, stylish, powerful, and efficient. Considering that every Chrysler model is in this same situation, each of these models must evolve as well. Maybe Fiat can see that this happens, if they do then Chrysler will be just fine.

Sunday, June 5, 2011

The Fluids Time Forgot

Isn't Everything Some Kind of Oil?

Most people know that oil should be changed regularly. Most people probably know that automatic transmission fluid should be changed regularly. They might even know that coolant should be changed at some point as well. What about some of the other fluids? If you are asking yourself right now, “There are other fluids?” then chances are you have neglected your car in some way or another. If you are wondering what other fluids your car has, and when they need to be replaced, check your owner’s manual.

The owner’s manual is truly the be-all-end-all when it comes to what services your car requires. You can find out exactly what services the manufacturer recommends and at what mileage or time intervals they recommend them. A few things don’t get mentioned in the owner’s manual but it’s not a bad idea to have these things serviced as well, especially if your car has high mileage.

Some other fluids your car might have are as follows:

Manual Transmission Oil

Anything with gears in it has to have some kind lubrication. While everyone knows something about automatic transmission fluid not many people know about manual transmission fluid. The oil that is used in a manual transmissions varies somewhat. The only thing that the fluid in a manual transmission must do is lubricate the gears and the shifting mechanisms.

The many gears of a manual tranmission

Manual transmissions usually use one of the following types of fluid, 75w-90 gear oil, automatic transmission fluid (ATF), regular motor oil such as 10w-30, or some kind of proprietary synthetic oil. The service interval for the fluid will ultimately be determined by the manufacturer, and it will also depend on what kind of fluid the manufacturer designed the transmission to use. The interval may be as often as every 30k miles, while some vehicles might not list any service interval and may even indicate that the fluid doesn’t require service for the life of the vehicle (or at least for the duration of the warranty period).

No dipstick is found for this oil, but it ought to be checked on a somewhat regular basis. A good lube shop will usually check this fluid when they are servicing the engine oil. Most of the time the service of a manual transmission requires a simple drain and refill of the fluid. A drain plug will be found at the lowest point on the transmission, and somewhere half way up the side of the case will be found a fill plug. After the old fluid is drained, new fluid will be pumped into the fill hole until it starts to run out the hole. At this point the transmission is full, and the fill plug is reinstalled. This is a very simple service which means that it’s easy to perform yourself, or easy for someone else to perform. Either way this means that it doesn’t cost much but it is something that most people seem to forget.

Brake Fluid

This must be serviced more often then any of the other forgotten fluids. Most vehicles require that the brake fluid be serviced every 2 years or 30k miles. Part of the reason for this frequent service interval is the fact that brake fluid is hygroscopic. This means that the fluid soaks up moisture from anything that it is exposed to. Keeping the moisture in the brake hydraulic system in check is important. Water is corrosive to just about everything it comes in contact with, and it also freezes. Both of these things are bad for the brake system.

A brake fluid reservoir perched on top of the brake master cylinder.
Brake fluid types don’t vary much at all from one make to another. Generally most manufacturers will use either DOT 3 fluid or DOT 4 fluid. The difference is that DOT 4 has a higher boiling point than DOT 3. Brake fluid is not petroleum based but is actually glycol based. This means that brake fluid is more similar to coolant in many ways than oil. DOT 3 and DOT 4 can be mixed with the only effect being that the boiling point of DOT 4 is no longer as high as it could be once it gets mixed with DOT 3. Synthetic brake fluid that is usually referred to as DOT 3-4 or DOT 5.1 is also compatible with DOT 3 and DOT 4. DOT 5 brake fluid is silicone based and should never be mixed with anything else. This fluid is usually used in very special applications such as auto racing.

The brake fluid condition is easy to check because the fluid reservoir is under the hood in a place that easy to access. Removing the cap is usually necessary in order to look at fluid condition. If the fluid is very dark then it probably needs to be serviced. If you have had your car for a long time but you don’t know if the fluid has ever been serviced, it probably needs to be serviced. If you just purchased your car recently and you don’t know if the brake fluid was ever serviced, it probably needs to be serviced. To service the brake fluid the entire hydraulic system must be flushed or bled. This requires a special tool to force all of the old fluid out, using positive or negative pressure at one end of the system or the other. This may also be accomplished by someone pumping the brake pedal while someone else opens a bleeder screw at each brake actuator. Brake bleeding is better left to someone with a little experience because if it isn’t performed properly the brakes will not work at all.

Power Steering Fluid

This is a special hydraulic fluid that is used to transmit force as well as lubricate. The fluid is stored in a reservoir where it is gravity fed into a pump. The fluid will be pressurized so that it can act against a piston in the steering gear assembly, and help push the piston in the direction that the vehicle is being steered. Some vehicles will use power steering pressure to provide pressure to the power brake booster that helps to actuate the brakes. The fluid is doing double duty in this instance.

A p/s reservoir attached diredtly to the pump.

Power steering fluid will break down over time and loose its ability to lubricate. Oxidation is also a problem just as it is with most other fluids in the vehicle’s various systems. Replacement intervals for power steering fluid are all over the map. Some experts say that it really doesn’t need to be serviced, and some would say to service it every 60,000 to 90,000 miles. All fluids break down over time and the properties that allow them to do their job are diminished, so every fluid must be serviced at some point.

The good news regarding power steering fluid service is that new technology is eliminating hydraulic power steering. Many new cars have electronic power steering that uses an electric motor to provide the assist. This is good because there is no pump and no fluid, which means no leaks, and more reliability.

P/S reservoir mounted away from the pump.
The type of power steering fluid that a car requires varies a little from one make to another but most of them require one of two different fluids. Standard power steering fluid is used by many vehicles. This fluid is just a special hydraulic fluid used to lubricate and transmit force. If the car doesn’t use standard power steering fluid, then it will probably use automatic transmission fluid. ATF is also a special hydraulic fluid that can transmit force and lubricate. Honda cars and trucks require a special “Honda Type” power steering fluid that is not compatible with regular fluid; many European cars might require some kind of specialized mineral oil. None of these fluids should ever be mixed.

Most power steering fluid reservoirs have either a small dipstick attached to the cap, or the reservoir is translucent so the level can be seen through the side of it. Servicing the power steering fluid is similar to servicing the brake fluid in that the system must be bled. This is not a process of ‘drain and fill’ like most fluids on the vehicle.  The best way to perform this service is to remove the return line from the reservoir, and direct it to a container to catch the old fluid as it cycles through. Start the engine and quickly pour new fluid into the reservoir to replace the old fluid as it flows out the return line into your catch pan. Some machines are available to help with this flushing process but they are not at all necessary.

Transfer Case Fluid

Any vehicle that has four wheel drive has an extra gear box on the back of the transmission that is responsible for splitting transmission output between the front wheels and the rear wheels. This device also contains gears that will multiply the torque output from the transmission. This device is the transfer case. Because it is full of gears and shafts and other rotating assemblies it too must be lubricated at all times.
A typical transfer case. The drain plug is the round thing at the bottom,
and the fill plug can be seen in the middle of the housing.
The fluid that is usually used in the transfer case can be 75w-90 gear oil, ATF, or any proprietary lubricating fluid that the manufacturer might come up with (ATF is amazing stuff, that’s why it gets used in all sorts of different things besides the automatic transmission). The average service interval for the transfer case is about 60,000 miles, but some manufacturers will claim it’s a lifetime fill and doesn’t require service. Service of the fluid is just a drain and fill similar to the manual transmission service.

Differential Fluids

The differential is the set of gears that make up the final drive and gear reduction in the power train. If you look under the back end of a rear wheel drive vehicle, this is the round box of gears that can be seen in the middle of the axle where the drive shaft connects to the axle. These gears split the power between the drive wheels, multiply torque one last time, and allow one wheel to turn faster than the other when the vehicle is turning.

Every drive axle must have a differential so any vehicle that has all wheel drive, or four wheel drive, will have two differentials, one for each axle. On a car with front wheel drive the differential is in the same housing as the transmission and most of the time they share the same fluid. This is why the transmission on a front wheel drive car is often referred to as a transaxle. A few front wheel drive cars have the differential and the transmission in the same housing but the fluid is not shared, nor is it the same type of fluid. Both fluids must be serviced separately.
Rear differential with the pan removed
Differential fluid must be serviced anywhere between every 15k to 90k miles, and of course some manufacturers say that their vehicle’s never require differential fluid service. Most differentials can be serviced through a simple drain and fill. Some of them do not have a drain plug however, and some kind of pan or cover must be removed so the fluid can flow out. Filling the differential requires pumping the new fluid in through the fill hole somewhere on the differential housing until it reaches the level of the fill hole.

The fluid is usually a gear oil such as 75w-90, but with all of the specialty differentials that are found on today’s SUVs and crossovers, some require a proprietary fluid that must be obtained from the dealer. Differentials that are known as “limited slip” require a special additive to go with the gear lube. This additive keeps the clutch packs located in this special type of differential conditioned in such a way that they will slip when needed and grip when needed.

Never Ending Fluids

Getting behind on fluid services is easy to do and therefore catching up again and getting things back on course is very difficult. The service schedules found in the owner’s manual will never let you down, and if you combine these recommendations with the recommendations that a trusted mechanic can make, you will never fall behind. None of these fluid services are difficult for a well trained service technician so none of them are very expensive all by themselves, but together it could be costly. Nevertheless fluid service is important and all of these things must be remembered. If they are forgotten, it will only lead to failure of the systems where they are found.