How you could stop your own BMW rear diff from being noisy like i did.
How do you make your BMW diff noise go away ?
Is it your diff or your wheel axle bearings ?
One way to tell is:
Drive your BMW in a straight line at a steady speed, say 40mph
Accelerate, then come off the gas, then on, then off.
Does the noise change pitch ?
Whine….no whine….whine ……no whine etc ?
If the noise can be “played” it’s almost sure to be your diff pinion bearings worn.
BMW E87 118d diffs are especially prone to this problem.
Then get a mechanic to do the same and get a professional opinion and maybe read.
This video shows a classic example of BMW 1 series diff noise, whining on and off acceleration.
What's inside your "How i rebuilt my BMW differential" book with over 110 pictures and easy to follow instructions ?
When you read inside you will find out how to:
1. Drain your oil and remove the rear cover.
2. Remove parts to gain access to hidden BMW diff retaining clips.
3. Learn how to keep some important parts in factory positions ( crucial).
4. How to remove the differential bearings safely.
5. Dismantle the pinion shaft quicker after removing an often unseen part.
6. How to replace the noisy BMW pinion bearings with good ones.
7. What important "tiny" diff part that should be renewed to ensure rebuild success.
8. How to easily set the pinion bearing preload
9. Easily refit the differential in the case without damaging the gears.
10. How you can properly check backlash between the gears is correct
11. Finally learn how to seal your diff ready for use again
What else is covered inside this BMW diff rebuild guide book ?
The information inside the book covers replacing your worn bearings and oil seals only, as this is the most common cause of noise and whine. The information covers BMW differentials built after about 2003 that use the tandem ball roller type bearings inside. This is most of the 1 series and 3 series E90/E92 cars, also many X3 and Z4 differentials used this setup inside.
All parts other than your bearings and seals must serviceable and in good condition. You can determine their condition before you purchase replacement parts once your diff is dismantled.
Ask a professional mechanics advice if you are unsure about any part.
What's NOT covered inside this BMW differential instruction guide ?
There is NO information inside about replacing or swapping gears for other ratios, replacing differential planetary gears, swapping casings or "uprating" etc. Although some information inside the book may be relevant to these procedures, this is not the purpose of this guide book.
If your differential has failed and requires more than bearing replacement you should get it professionally inspected and repaired or get a new factory diff.
As a guide often prices for this can cost upwards of $1700 USD, £1200 GBP or 1400 euros before the extra fitting charges and local sales tax.
This book will still however give you some inside knowledge as to what's inside your noisy differential so you can determine whether to buy a new BMW part, get it repaired by a specialist or buy a pre-used item.
Finally, even if you decide against undertaking the work yourself, your book may help you make a decision about what to do next to solve your BMW differential noise problem.
Buy your copy of this book with over 110 pictures here and get it sent now !