Parts Catalog Accessories Catalog Tech Info Tech Forums
 
Follow Pelican Parts on Facebook Follow Pelican Parts on Twitter Follow Pelican Parts on Instagram Follow Pelican Parts on YouTube Follow Pelican Parts on Pinterest Follow Pelican Parts on Tumblr
  Search our site:    
View Recent Cars  |   Cart  | Project List | Order Status | Help    
 >  >
Rear Differential Fluid Replacement
 
Bookmark and Share

Pelican Technical Article:

Rear Differential Fluid Replacement

Nick Czerula

Time:

1 hour1 hr

Tab:

$30

Talent:

*

Tools:

14mm Allen bit, drain pain, oil quart container pump

Applicable Models:

BMW Z4 Coupe/Conv (2006)

Parts Required:

Differential oil, differential plugs (2)

Hot Tip:

Drive car for short distance to warm oil

Performance Gain:

Extend differential life

Complementary Modification:

Replace manual transmission fluid

The rear driveshaft transfers the rotation of the transmission (or transfer case) output shaft to the input shaft of the rear differential. Inside the differential the axis of rotation is turned 90 degrees. Using specially designed planetary gears, the differential also splits the power in order to accommodate cornering: the two rear wheels must be allowed to rotate at different speeds in a turn. The output flanges of the differential connect to the drive axles which power the rear wheels.

The oil in your rear differential is considered lifetime by BMW. This does not mean you shouldn't service it. When a vehicle manufacturer refers to a component as lifetime, the time period is usually 100,000 miles or so. So your differential oil lifetime is 100,000 miles, but what does this mean when it comes to servicing? The oil in the rear differential lubricates the bearings and gears that drive the rear wheels of your Z4M. You want these items to last, and with routine maintenance, they will. I suggest replacing your differential fluid every 4 years regardless of mileage. It's a good idea to check the fluid every time you change your oil and top off if necessary. Your rear differential will hold about 1 liter (M models 1.5 liters) of oil, but have a little more on hand in case you spill it.

Keep in mind that when your car was serviced before, parts may have been replaced with different size fasteners used in the replacement. The sizes of the nuts and bolts we give may be different from what you have, so be prepared with different size sockets and wrenches.

Protect your eyes, hands and body from fluids, dust and debris while working on your vehicle. If working with the electrical system, disconnect the battery before beginning. Always catch fluids in appropriate containers and properly dispose of any fluid waste. Recycle parts, packaging and fluids when possible. Do not work on your vehicle if you feel the task is beyond your ability.

Vehicle models change and evolve as they grow older, so the vehicle shown in our illustrations may vary slightly from yours. If something seems different, let us know and share your info to help other users. Questions or want to add to the article? Leave a comment below. When leaving a comment, please leave your vehicle information.

The rear driveshaft transfers the rotation of the transmission (or transfer case) output shaft to the input shaft of the rear differential (red arrow).
Figure 1

The rear driveshaft transfers the rotation of the transmission (or transfer case) output shaft to the input shaft of the rear differential (red arrow). Inside the differential the axis of rotation is turned 90 degrees. Your rear differential will hold about 1 liter (M models 1.5 liters) of oil, but have a little more on hand in case you spill it. Drive vehicle for about 2-3 minutes to warm the differential oil. Next, lift and support the front and rear of the vehicle. You want the rear differential to be level when filling or checking the oil level.

The splash shield for the drivetrain has to be removed.
Figure 2

The splash shield for the drivetrain has to be removed. Start in front of the differential, remove the six 8mm fasteners (red arrows).

Then remove the final two 8mm splash shield fasteners (red arrows).
Figure 3

Then remove the final two 8mm splash shield fasteners (red arrows). Support the splash shield as you remove the final fastener.

Remove the splash shield (red arrow) from the vehicle.
Figure 4

Remove the splash shield (red arrow) from the vehicle.

With the splash shield removed, you now have access to the fill (red arrow) and drain plug (purple arrow).
Figure 5

With the splash shield removed, you now have access to the fill (red arrow) and drain plug (purple arrow).

Working at rear differential, using a 14mm Allen bit, remove the oil fill plug (red arrow).
Figure 6

Working at rear differential, using a 14mm Allen bit, remove the oil fill plug (red arrow). There isn't a lot of room for ratchet, I use a 14mm wrench over my Allen bit. To check the fluid level, insert your finger into the fill hole, oil level should be at the bottom of fill plug opening. Be sure to wear clean gloves.

Next, using a 14mm Allen bit loosen the differential oil drain plug.
Figure 7

Next, using a 14mm Allen bit loosen the differential oil drain plug.

Remove the differential oil drain plug (red arrow).
Figure 8

Remove the differential oil drain plug (red arrow). Drain the oil into a suitable container with a 4 liter capacity (purple arrow). Once the oil has completely drained, reinstall the drain plug, I suggest replacing it.

Pump the oil into fill plug hole until it runs out (red arrow).
Figure 9

Pump the oil into fill plug hole until it runs out (red arrow). Allow oil to stop dripping or come to a slow drip, then reinstall fill plug and torque to specs. Inset shows drain and fill plug with integrated sealing O-ring, replace when removed. Once finished, take vehicle for a short ride and check the rear differential for leaks.

Bookmark and Share

  Search our site:    

View Cart & CheckOut | Project List | Order Status |  Help    

 

[Home] [Customer Service] [Shopping Cart] [Privacy Statement]
 [Contact Us] [About Us] [Shipping] [Map to our Location] [Careers]

Copyright © Pelican Parts Inc.

Page last updated: Fri 12/9/2016 03:01:53 AM