When you feel your vehicle vibrating as you're driving down the road, one cause could be something you may not have ever seen: your driveshaft.  It is underneath the vehicle and most drivers don't climb under there to take a look very often.  The driveshaft is a cylindrical part that helps conduct the rotational power from your engine to your drive wheels.  If you have a four-wheel drive vehicle, you may have two driveshafts. 

The drive shaft has bushings, and when they wear out, that's a likely source of the vibrations.  When the bushings are in good condition, they prevent the driveshaft from vibrating.  And if you don't get your vehicle repaired fairly soon after discovering vibrations, they'll continue to get worse and cause other components of the drivetrain to wear out.

The driveshaft is, of course, only one part of the drivetrain.  It includes other parts such as axles, transmission, differentials and joints.  They all work together and need to be maintained properly.  When a driveshaft fails, there can be symptoms other than vibrations.  They include difficulty turning, rattles, clunks and squeaks coming from underneath your vehicle. You may even feel a shudder when you accelerate from a stop.

Driveshafts can fail when they get corroded or damaged by rough roads, curbs and debris. A trained technician with experience working on drivetrains uses specialized equipment that doesn't further damage the drivetrain's other parts.  Sometimes the entire driveshaft will have to be replaced; sometimes the problems can be fixed by replacing individual components. 

Your vehicle's drivetrain was engineered to propel you smoothly down the road.  When time and distance begin to take their toll, have your vehicle looked at by your service facility. They'll know how to properly pinpoint what's causing your problems and restore your vehicle to the reliable, smooth, safe machine its designers worked hard to create.

PDR
1008 N. Cunningham Avenue
Urbana, Illinois 61802
217-367-9481
http://www.pdrauto.com

Some people love 4x4 vehicles, the true 4-wheel drive works of engineering like Jeeps and 4x4 pickups that allow you to seemingly go anywhere on the planet. You can climb up a 40-degree rock trail with some planning and skill (always careful to protect the environment, of course), or you can get through the deepest snow.

But with that added capability comes additional complexity, drive-train components and other systems that less capable vehicles don't have.  And that is why when it comes to 4x4s, you have to maintain them a little differently from those vehicles that spend their lives on pavement.  Here are some of the key things to keep an eye on:

• Transfer case—This transfers power from the engine to the wheels.  A transfer case has fluid in it that needs to be changed at intervals recommended by the manufacturer.  Your service advisor will let you know how often that is and will keep track of your service dates.  You will need to make sure the transfer case seal is working properly.  Otherwise, transmission fluid could get in and cause damage that is costly to fix.  Some transfer cases have an electric motor that shifts it through gears, and its connections are often exposed to the elements, making them vulnerable to damage and corrosion.  Proper maintenance will keep those connections working like they should
• Front and rear differentials—These also have to have the right amount of fluid and should be checked regularly.  Your service advisor can let you know when you need that fluid changed as the owner's manual recommends.  It's important the service is performed correctly with the proper lubricant so it will work the way it is designed to.
• Brake lines—Those 4x4s practically beg to go into wet spots. They also are great machines to conquer snow: road salt, brine and all.  Moisture, salt and brake lines are a recipe for corrosion, so brake lines need to be inspected regularly.  There are anti-corrosion sprays or white lithium grease that can retard corrosion.  Remember, getting there is half the fun, but not being able to stop is no fun at all.

So enjoy your 4x4 and what it can do that other vehicles can't.  Just remember that even though it's tough on the outside, it needs special care to keep it going.  Oh, and remember to take care of the environment when you go off-roading, too. 

There are a lot of drivers in Urbana who are due for a differential service, but had never heard of a differential before. With front-wheel drive being so common in Illinois these days, the differential is just taken care of during a transmission service, so most Urbana folks don't even have to think about it. And rear-wheel drive differentials don't need to be serviced for years, so it's understandable that it's not something on the top of your mind. It's not uncommon for people in Urbana to not know they have a differential, let alone know that it needs service.

To better understand what a differential does, think about a track at any Illinois high school. There are lanes marked off on the track. For the longer distance races, the starting lines are staggered. The starting lines for the outside lanes are ahead of the starting lines for the inside lanes. That's to compensate for the longer length of the outside lanes. Staggering the starting lines means that each runner has the same distance to run.

The differential compensates for the difference in speeds between the inside vehicle wheel and the outside wheel in a turn, because they have to travel together through slightly different distances.

It's a very important function. When you think of it, all the power to get a vehicle moving goes through the differential. Most cars weigh between 3,000 and 6,000 pounds (1,400 and 2,800 kg) – trucks even more. The power from the engine goes through the transmission and then through the differential to the drive wheels.

That's a lot of work and requires very heavy duty parts. And those parts need protection. The differential fluid lubricates the gears in the differential and keeps them cool. The fluid eventually gets dirty and worn down. Some kinds of differentials require special additives that break down over time. So manufacturers recommend intervals for when to replace your differential fluid.

Your knowledgeable PDR service technician will drain the used fluid and check it out for metal bits, which could be a sign of excessive wear on the gears. He'll then replace the fluid and install the additives if necessary.

Your PDR service advisor can look up the vehicle manufacturer's recommended service interval or you can check your owner's manual.

At PDR, we've been providing quality automotive service for our valued Urbana customers since . If you need to schedule differential maintenance, or any other automotive service, give us a call at 217-367-9481.

PDR
1008 N. Cunningham Avenue
Urbana, Illinois 61802
217-367-9481
http://www.pdrauto.com

Hello Urbana - let's talk differentials. If you have a rear-wheel drive vehicle, your differential is on the back axle. With front-wheel drive cars, the differential is up front. All-wheel drive and 4-wheel drive vehicles have three differentials - front, rear and in the middle. So you see, you've got a differential (or two or three) and it needs service now and then.

What does your vehicle differential do? Well, it compensates for the differences in speed between your outer and inner wheels in a turn. Using the dimensions of a typical car, let's compare the distance the wheels travel from the start of a turn through to the completion of the turn.

The inside wheel travels about 12.6 feet/3.8 meters. How much farther does the outside wheel travel? About 18.8 feet/5.7 meters – over 6 feet/1.9 meters more. This means the outer tire has to rotate 9 times in the same amount of time that the inner tire has to rotate only 6 times - so the outer tire has to spin faster in order to keep up. The differential makes this possible.

The gears in the differential are cooled and lubricated by differential fluid. It's this fluid that needs to be serviced. Small bits of the gears break off and are suspended in the differential fluid. The dirtier the fluid, the faster the gears wear.

So your PDR technician drains the old fluid out and replaces it with fresh fluid. Some differentials also need a special additive that is put in at this time.

So when should you have your vehicle differential serviced? Intervals vary from vehicle to vehicle – and may be as short as 15,000 miles/24,000 km – so check your vehicle owner's manual or ask us at PDR. If you frequently drive with heavy loads, tow a trailer or drive in hot Illinois conditions, you may need to change differential fluid more often. Servicing your differential on schedule at PDR can save a pricey replacement down the road.

Give us a call.

PDR
1008 N. Cunningham Avenue
Urbana, Illinois 61802
217-367-9481
http://www.pdrauto.com

Scratching your head? Don't worry, if you don't know what a differential is – you will in a moment. That fact is that if you drive a car anywhere in Urbana, Illinois, you have a differential. Whether your vehicle is front-wheel drive, rear-wheel drive or four-wheel drive, you have a differential. Some Urbana vehicles might even have two or three.

Not surprisingly, a differential's job is to compensate for differences; specifically, they're the differences in wheel speed when turning. For instance, imagine taking a corner near your Urbana, Illinois, home. Your inside wheel has a shorter distance to travel than the outside wheel as you turn the corner. That means that your outside wheel has to turn faster to keep pace with the inside wheel.

The differential allows the wheels to turn at different speeds while still providing power to your vehicle. Without a differential, Urbana residents' tires would scrub and hop along the pavement during turns like the early cars.

Ever noticed the big bulge in the middle of the rear axle on trucks? That's the differential. Rear-wheel drive vehicles have a differential in back. Most four-wheel drive trucks and SUVs will also have a similar differential on the front axle. A front-wheel drive vehicle's differential is called a transaxle because it combines the differential and transmission in one unit. An all-wheel drive vehicle will have a differential or transfer case that adjusts for speed differences between the front and rear drive wheels.

It can seem a little complex to some Urbana drivers - but you can see that all of the engine's power is routed through your differentials. They're strong enough to handle the work, but- we've said it before - they need to be properly lubricated in order to stay strong. So from time to time, you need to schedule a differential service in Urbana at PDR. The used fluid is drained and replaced with clean fluid. Some advise certain differentials to have special additives installed.

Get your differential serviced at PDR in Urbana.

PDR
1008 N. Cunningham Avenue
Urbana, Illinois 61802
217-367-9481
http://www.pdrauto.com

The drive train in your vehicle includes all the components that transfer power from the transmission to the wheels. Those components differ depending on what type of vehicle you drive, namely, front-wheel drive, rear-wheel drive, all-wheel drive or four-wheel drive. The preventive maintenance your driveshaft needs will also differ by what type of vehicle you drive.

Let's start with front-wheel drive. In this vehicle, the transmission and the differential are combined in one component, known as the transaxle. The transaxle is connected to two half-shafts (axles), which are then connected to the wheels with a constant velocity (or CV) joint, which is protected by an airtight rubber boot.

PDR service for this type of driveline includes servicing the transaxle and inspecting the CV boot. If the boot is damaged, the CV joint will need to be inspected, and the boot will need to be replaced. If you hear a clicking noise in your wheel wells when you turn, you may have a damaged CV joint. A damaged CV joint should be replaced.

Rear-wheel drive vehicles generally have a transmission in the front of the car and the differential in the back. A driveshaft (it looks like a long tube) connects the transmission to the differential. Some vehicles may have a two-piece driveshaft, which are connected to the differential with universal joints or U-joints. Again, the differential is connected to two half-shafts that go out to the wheels.

PDR service on the drive train on a rear-wheel drive vehicle starts with servicing the differential. It will need its fluid drained and replaced regularly. The seals on the axles should also be inspected for wear or leaks. Leaking or damaged seals may mean the axle needs to be serviced as well. Also, U-joints can wear out. If you hear clunking or feel a jolt when you shift into drive or into reverse, it could indicate a driveline problem.

All-wheel drive vehicles provide power from the transmission to all of the wheels, instead of just to the front or rear. The advantage is that the vehicle can adapt to different driving conditions and transfer more power to the front or back wheels as needed. The disadvantages are that the driveline is more complicated, and the vehicle weighs slightly more.

Many all-wheel drive vehicles are based on a front-wheel drive set-up. They also have a differential in the rear and one in the center of the vehicle that allows power to transfer to the front and rear. A shaft runs from the transfer case to the center differential, and another from the center differential to the rear differential.

Servicing an all-wheel drive at PDR involves servicing ALL of the differentials and inspecting the joints and seals for wear, leaks or damage.

Four-wheel drive vehicles are rear-wheel drive vehicles that have an option to transfer power to the front wheels. In other words, they can be driven as either rear-wheel or four-wheel drive vehicles. These vehicles are specifically designed for the harsh driving conditions Urbana drivers encounter off-road. The driveline in a four-wheel drive vehicle is similar to that of an all-wheel drive vehicle. The center differential, however, is a transfer case. Maintenance requires servicing both of the differentials and the transfer case, as well as an inspection of the joints and seals.

Urbana auto owners would be wise to check with their owner's manual for recommendations on how often to service their vehicle drive train. It's also good auto advice to check with your friendly and knowledgeable PDR service advisor as well. You may live in an area in Illinois where weather or driving conditions require more frequent servicing of the drive train.

Good car care at PDR in Urbana always includes taking care of your driveline. Without it, your vehicle becomes a very large paperweight.

PDR
1008 N. Cunningham Avenue
Urbana, Illinois 61802
217-367-9481
http://www.pdrauto.com

Here at AutoNetTV, we have national viewers, like your neighbors in Urbana, who write to us with questions or feedback. One common question we're asked is: "What is a differential and what does it do?" You may have been told by your PDR service advisor that your differential needs serviced, or it's seen it as an option up on the service menu. Differential service at PDR covers a lot of things, so let's first talk about what a differential does.

As you drive through a turn, your outside wheels and inside wheels turn at different speeds. Kind of like the cars going around a race track - the ones driving in the outside lanes have a greater distance to travel than the cars in the inside lanes. The differential is what allows the outside and inside drive wheels to rotate at slightly different speeds so that the tires don't hop or skip while taking corners, or lose traction in dirt or snow on Urbana area roads. Differentials have gears in them that transfer the power from the drive train to your wheels - which is why they're often referred to as gear boxes. The gears need to be very strong to do this work, and they need to be properly protected so that they'll last.

All vehicles in Urbana have some form of differential. If you have a front-wheel drive car, your differential is sometimes called a transaxle and is located in the front. If you have rear-wheel drive, the differential is in the back of the car. Urbana auto owners with a four-wheel drive vehicle have a differential in the front and the back - and in the middle as well. The center differential adjusts for differences in speed between the front and rear wheels.

Differential fluid lubricates and cools the gears. Over time, the fluid can get dirty from bits of the gears grinding off. The additives that keep the fluid clean and protect the differential break down over time. So your vehicle manufacturer has scheduled intervals for you to have your differential fluid changed. Talk to your friendly and knowledgeable PDR service advisor if you are not sure about your recommended schedule.

PDR
1008 N. Cunningham Avenue
Urbana, Illinois 61802
217-367-9481
http://www.pdrauto.com

With front-wheel drive being so common these days in Urbana, Illinois, the differential is just taken care of during a transmission service, so most Urbana drivers don't even have to think about it. And rear-wheel drive differentials don't need to be serviced for years, so it's understandable that it's not something on the top of Urbana customers' minds. It's not uncommon for drivers to not know they have a differential let alone know that it needs service.

Call PDR in Urbana at 217-367-9481 for information about differential service, or stop by our Urbana, Illinois, auto center at 1008 N. Cunningham Avenue, 61802.

To better understand what a differential does, think about our local Urbana high school track. There are lanes marked off on the track. For the longer distance races, the starting lines are staggered. The starting lines for the outside lanes are ahead of the starting lines for the inside lanes. That's to compensate for the longer length of the outside lanes. Staggering the starting lines means that each runner has the same distance to run.

The differential compensates for the difference in speeds between the inside wheel and the outside wheel in a turn, because they have to travel together through slightly different distances.

It's a very important function. When you think of it, all the power to get a vehicle moving goes through the differential. Most cars in the Urbana, Illinois area weigh between 3,000 and 6,000 pounds (1,400 and 2,800 kg) – trucks even more. The power from the engine goes through the transmission and then through the differential to the drive wheels.

That's a lot of work and requires very heavy duty parts. And those parts need protection. The differential fluid lubricates the gears in the differential and keeps them cool.

The fluid eventually gets dirty and worn down. Some kinds of differentials require special additives that break down over time. So vehicle manufacturers recommend intervals for replacing your differential fluid.

The professionals at PDR will drain the used fluid and check it out for metal bits, which could be a sign of excessive wear on the gears. Then they’ll replace the fluid and install the additives if necessary.

Your PDR service advisor can look up the vehicle manufacture's recommended service interval or you can check your owner's manual. Give us a call at 217-367-9481 for more information about your differential service.

PDR
1008 N. Cunningham Avenue
Urbana, Illinois 61802
217-367-9481
http://www.pdrauto.com

Don’t be embarrassed if you don’t know what a differential is; you will in a moment. That fact is that if you drive a car, you have a differential. Whether your vehicle is front-wheel drive, rear-wheel drive or four-wheel drive, you have a differential. You might even have two or three.

As you might guess from the name, a differential’s job is to compensate for differences. Specifically the differences in wheel speed when turning. For instance, imagine taking a corner. Your inside wheel has a shorter distance to travel than the outside wheel as you go around the corner. That means that your outside wheel has to turn faster to keep pace with the inside wheel.

The differential allows the wheels to turn at different speeds while still providing power. Without a differential, our tires would scrub and hop along the pavement during turns.

You’ve probably noticed the big bugle in the middle of the rear axle when you’re behind a truck. That’s the differential. Rear-wheel drive vehicles have a differential in back. Most four-wheel drive trucks and SUVs will also have a similar differential on the front axle.

Front-wheel drive vehicles’ differential is called a transaxle because it combines the differential and transmission in one unit. An all-wheel drive vehicle will have a differential or transfer case that adjusts for speed differences between the front and rear drive wheels.

It can seem a little complicated. But you can see that all of the engine’s power is routed through your differentials. They’re strong enough to handle the work, but they need to be properly lubricated in order to stay strong. So from time to time, you need to have your differential serviced. PDR Automotive Repair can service your differential. The used fluid is drained and replaced with clean fluid. Some differentials also require special additives to be installed, and at PDR Automotive Repair we can help you with that, too.

The rule of thumb for the time and mileage interval for servicing your differential can vary greatly by vehicle. A front-wheel drive vehicle’s transaxle will need servicing more frequently than the rear differential on a pick-up truck, so check with your service advisor or your owner’s manual for recommendations.

How and where you drive will have an impact as well. If you drive on dirt roads or through streams in the Champaign area, you’ll need to service the differential at PDR Automotive Repair much sooner than if you always stay on the local Champaign pavement.

One Urbana automotive service issue that doesn't get much attention is driveline service. Drivelines don't get talked about very much around Urbana, but they're very important. First let's define what the driveline is:

Taking a small step back, the power plant is comprised of the engine and transmission. The driveline starts there and includes all of the components that transfer power from the transmission to the wheels.

That's not really a lot of components, but they handle the full force of the engine. Without the driveline you're not moving. So Urbana residents need to take good care of it. The driveline components differ depending on whether your vehicle has front wheel drive, rear wheel drive, all wheel drive or four wheel drive. For purposes of our discussion, we're going to have to oversimplify a bit.

If you are ready to have your drive train looked at, give us a call at 217-367-9481.

Let's start with front wheel drive. The point where the transmission stops and the driveline begins is a little blurred with front wheel drive because the transaxle houses both the transmission function and the differential function. The half shafts that send power to each front wheel come out of the transaxle. The shaft is connected to the wheel by a constant velocity, or CV, joint. The CV joint is protected from dirt and water by an airtight, flexible rubber boot.

So, PDR driveline service would include properly servicing the transaxle and inspecting the cv boot to see if it's torn or loose. If it is, it needs to be replaced and the CV joint inspected for damage. Repairs may be in order. Besides visual damage to the airtight CV boot, you might hear a clicking noise when turning. Recommended maintenance for the transaxle and CV joints will be spelled out in your owner's manual, or check with your friendly and knowledgeable PDR service advisor.

On to rear wheel drive. The driveline for a rear wheel drive vehicle starts with the driveshaft – that long tube that connects the transmission with the differential on the rear axle. Some vehicles in Urbana have a two piece drive shaft. The shafts are connected to the transmission and the differential with big universal joints. Most Urbana residents have probably heard the term 'u-joints.' These joints can wear out, just like the CV joints in front wheel drive vehicles. You may hear some clunking or feel a jolt when shifting into drive or reverse – if you do, get your driveline inspected at PDR in Urbana.

The differential on the rear axle sends power out to each rear wheel through half shafts in the axle. The differential fluid needs to be drained periodically and replaced with clean fluid. When the seal on the end of the axle is damaged or leaks, the axle will need to be serviced. The routine maintenance item here is differential service. Be sure to check your owner's manual or Urbana service advisor for intervals.

Now let's go on to all wheel drive. Remember that the difference between all wheel drive and four wheel drive is that an all wheel drive vehicle is essentially providing power to all of the wheels all of the time. The vehicle may be able to shift more of the power to the front or to the back depending on where you need traction. All wheel drive vehicles are designed to work well on dry pavement. Even some high-end sports cars from makers like Lamborghini and Porsche have all wheel drive.

Some all wheel drive vehicles are designed to work well off-road in Urbana, but all hard-core rock crawlers are four wheel drive. These guys thrive in mud, sand, rocks and hills – but they don't work well on dry pavement when they're in four wheel drive. So they have the option to shift to rear wheel drive only on dry pavement.

Most all-wheel drive vehicles are very similar to front wheel drive when it comes to the front end. They also have a center differential that transfers power to the rear differential. Connecting it all is a shaft from the transaxle to the center differential and another from the center differential to the rear differential. So all of the normal front wheel drive service is recommended as well as service to the center and rear differentials.

Four wheel drive can be thought of as a rear wheel drive vehicle that can also send power to the front axle. There's a transfer case in the middle of the vehicle that can be shifted to send power through a drive shaft to a differential on the front axle. So Urbana residents need differential service for the front and rear differentials and for the transfer case as well.

The bottom line for Urbana residents is that the maintenance schedules are in your owner's manual. Your Urbana service advisor can answer any questions you've got. If this is the first time you've heard some of this stuff – it's time to ask someone at PDR if any of it needs to be done now.

PDR
1008 N. Cunningham Avenue
Urbana, Illinois 61802
217-367-9481
http://www.pdrauto.com