So Fix it

Drive shafts are used on all cars to connect the rear differential to the engines transmission. If you have a large vehicle like an SUV or a van, your vehicle will have a center bearing. This is also known as a carrier bearing. This bearing is used to support the drive shaft on the car. You dont have to be a car mechanic to replace your bearing. You can do it yourself with little hassle and minimal knowledge of the replacement.

Instructions

1

Jack up your vehicle so you have access to the bottom of the car. Put jack stands under the frame to support vehicle so it is not being support solely by the jack.

2

Use a piece of tape to mark where the transmission and the drive shaft are. The drive shaft is a splined shaft on the bottom of your vehicle. Mark where the universal joint connects to the rear axle differential.

3

Remove the bolt holding the drive shaft to the car. Remove the drive shaft center bearing from the frame with a socket wrench.

4

Use your wrench to remove the bolts holding the universal joint bearing to the yoke. This is coming out of the cars rear axle differential. Secure the caps at the bottom of the car with a piece of duct tape so they do not fall out.

5

Pull the drive shaft out of the cars transmission. Use a socket wrench to remove the bolts that are securing the universal joint bearing to the cars yoke coming out of the vehicles rear axle differential.

6

Use your wrench to remove the bolts from the drive shaft plate. Pull the rear plate off of the drive shaft. Secure the front plate to the drive shaft with a vise. Use your wrench to remove the nut from the center of the drive shaft.

7

Use a hammer to remove the old bearing from the drive shaft. Use a brass-ended punch so you do not scratch the shaft. Put a thin layer of car grease into the bearing shaft. Push your new bearing into the drive shaft and then hammer the bearing into place.

8

Reassemble your cars drive shaft in the reverse order that you took it apart.

The BMW 740 is large luxury sedan that delivers limousine comfort in a sporty chassis. The 7 series is so good that it actually serves as the base for many Rolls Royce cars, which BMW also makes. However, it has a lot of electrical gadgets that can go bad, necessitating the removal of the center console to gain access to certain components. Alternatively, you can replace a faded or damaged center console with a replacement to resh the look of the interior.

Instructions

1

Drive the BMW 740 into your garage or driveway because if you perform this removal procedure on the side of the road it will look like you are stealing the stereo. Place the 740 in "Park" and pull the emergency brake to make sure it does not shift while you are working on it. Make sure the car is off before you continue.

2

Pull the two plastic cup holders out from the center arm rest by hand. Unscrew the Philips head screws at the bottom of the cup holder holes. Go to the back seat of the 740 and pull the ash tray out from the rear of the front center arm rest. Unscrew the two Philips head screws that are underneath. Pull the center arm rest up and then back and place it to the side so that it does not get bent. Pull the emergency brake jacket off and the center plastic bezel from around the shifter.

3

Pry the bottom of the center console bezel up with a flat screwdriver. Be very gentle, as you can easily crack the plastic. Work the screwdriver in the seam between the center console bezel and the rest of the dash. Pull the center console bezel straight back and then up once all the pegs are disengaged. Place the center console somewhere safe, as it too is prone to cracking.

Depending on your perspective, an off-center steering wheel can be a truly infuriating experience, all the more so when the car doesnt pull to either direction. Theres something about this condition that just seems to baffle the human mind; how can the car be going straight when the wheel is turned? But the reason for a steering wheel turn, and the subsequent fix, is actually pretty simple once you understand what went wrong.

Steering Basics

Your steering wheel connects to a steering column. At the end of that column is a gear called a pinion, and that pinion meshes onto matching teeth on top of a flat bar called a rack. When you turn the pinion, it pushes the rack to the left or the right. The ends of the rack connect to tie rods, which in turn connect to arms extending backward from the wheel hubs. On the tie rods youll find a threaded collar; turning it makes the tie rod longer or shorter, angling the wheel inward or outward. Of course, this describes only a rack-and-pinion system, but most steering systems are functionally identical where the steering linkage is concerned.

Rear Toe and Steering

Most cars also have a second bar running from side-to-side in the rear, and those that dont typically have some provision to turn the axle one direction or the other. While it may seem a bit strange, the rear axle and its tie rods are just as responsible for steering your car as the front. The difference is that the rear axle only turns the rear of the car. If your rear alignment settings -- via the tie rods or axle alignment -- are off, youll have to turn the wheel in the same direction as the rear tires to keep the car pointed down the road. This alone will cause your steering wheel off-center, because the car is actually going down the road slightly sideways.

Alignment Problems

An off-center steering wheel is, paradoxically, a pretty common complaint following a front-wheel alignment. During an alignment, the technician will adjust your front tie rods to whatever degree necessary to remove any pull on the steering wheel. In the course of doing so, hell end up changing the position of the wheels relative to the steering column just to keep them pointed in the same direction as the rear tires. While this does eliminate that sideways pull, itll also permanently cock your car sideways. This "off-tracking" or "dog-tracking" is dangerous because it changes your cars low and high-speed handling characteristics, and itll kill your fuel economy by exposing the broad side of your car to the wind.

Dialing Out the Turn

Since this is essentially a problem with rear wheel angle, you need to adjust that first. The simplest way is to take your car to an alignment shop and have them perform a four-wheel alignment. If youre doing it yourself -- which you shouldnt unless youve got the right equipment -- then you need to get the rear wheels pointed perfectly straight first. Then, youll need to start the engine, turn the wheel a couple of times to relieve pressure from the power steering system. Shut the car down with the wheel locked in a straight-ahead, 12-oclock position. Finally, adjust the front tie rods to get the wheels straight. At this point, the problem is essentially fixed and your car is once again pointed straight, but youre not quite done yet.

Setting the Toe

While it might sound odd, most cars arent going down the road with all four wheels pointed straight forward. Many have a certain degree of front or rear "toe." Toe-in means the front of the wheels point inward, or sort of cross-eyed. Toe-out means they point slightly outward. Different manufacturers and drivers per different degrees of toe-in or -out for a given car. Toe-in makes that axle more stable on the highway and under braking by causing the wheels to constantly try to turn toward each other. Toe-out causes that axle to change direction more quickly at the expense of stability. A zero-toe setting does nothing for directional stability either way, but is the hypothetical optimum for fuel economy. Setting toe is vital for your cars performance and safety, and its somewhat difficult to measure without the right equipment. So, unless you really know what youre doing, these sorts of alignment settings are best left to professionals.