Diff Oil

[milesz]

What's a good diff oil to use? Is Castrol Syntrax™ Limited Slip Gear synthetic oil a good oil to use or what you guys are using?

Thanks

[williamx5]

Good day!!

First off, what are we working with? It might help us help you if you had all the vehicles you deal with in the signature block... You never have to worry about including the information in any posts again...

Unless a limited slip was actually custom added to your X5, no matter the year or motor size, you don't need LSD fluid... I think BMW uses 75W90... I'm going to check really quick... Be right back...

https://www.google.com/search?q=8322...&bih=924&dpr=1

Yep... OEM stuff comes in liter bottles... You can use the equivalent full synthetic version from any quality names... Mobil 1 is the stuff I use...

Cheers!!!

[milesz]

Originally Posted by williamx5

Good day!!

First off, what are we working with? It might help us help you if you had all the vehicles you deal with in the signature block... You never have to worry about including the information in any posts again...

Unless a limited slip was actually custom added to your X5, no matter the year or motor size, you don't need LSD fluid... I think BMW uses 75W90... I'm going to check really quick... Be right back...

https://www.google.com/search?q=8322...&bih=924&dpr=1

Yep... OEM stuff comes in liter bottles... You can use the equivalent full synthetic version from any quality names... Mobil 1 is the stuff I use...

Cheers!!!

Thanks Willianx5, I look into add my info in the signature black.

[Bmwtvboy]

He's correct. 75-90 W is what I use every 100K miles. I do both front and rear, although getting to the front is more time consuming. Not due until I reach 300K. Good luck.

[PR1AWRet]

I run synthetics in the engine (5W30), transfer case (ATF+4), and differentials (75W90). Any major brand. If differential oil says it has the added ingredients for limited slip you can still use it without any problems.

[wpoll]

Originally Posted by PR1AWRet

I run synthetics in the engine (5W30), transfer case (ATF+4), and differentials (75W90). Any major brand. If differential oil says it has the added ingredients for limited slip you can still use it without any problems.

Only pre-facelift cars (1999-2003) can use ATF in the transfer case - the later model XDrive cars require the special BMW fluid.

For all diffs though - this: -



https://www.redlineoil.com/product.aspx?pid=133&pcid=4

[oldskewel]

If "diff oil" means the oil to put in your differentials, one of the most important things to be sure of is that it is GL-5 (and not GL-4, which would more commonly be used in a manual transmission).

Careful inspection of the oil you drain out may be helpful.

Changing the front differential oil will probably require removing the stiffening plate, along with the famous (or infamous) bolts. Set aside some time before delving into that topic.

[bcredliner]

As mentioned, what year model do you have?

[semcoinc]

Originally Posted by oldskewel

If "diff oil" means the oil to put in your differentials, one of the most important things to be sure of is that it is GL-5 (and not GL-4, which would more commonly be used in a manual transmission).

Careful inspection of the oil you drain out may be helpful.

Changing the front differential oil will probably require removing the stiffening plate, along with the famous (or infamous) bolts. Set aside some time before delving into that topic.

Did the stiffening plate removal a few months ago for my front axle shafts and one of the best tips I've seen for dealing with this is to only remove THREE bolts and loosen the 4th one to allow the plate to pivot for access. Pick which way you need the clearance and then select the appropriate bolt to leave loosely fitted.

Worked great for me and yes, I reused the nuts and bolts and thousands of miles later, nothing has snapped apart on the freeway.

For front and rear diff fluid I use this



AMSOIL Severe Gear® 75W-90

http://www.amsoil.com/lit/databulletins/g2043.pdf

Mike

[bcredliner]

Since diff, transfer case and transmission fluids do just fine for so long I see no reason to use anything other than OE fluid where there is no question that it meets the specs and no risk there it will cause a problem.