I hope that some of you gear heads can maybe explain to me the REAL reason for BMW's Front & Rear Differential GL5 viscosity fluid change.
I own & maintain 5 current BMW's of different years & models (92 E34 535i, 01 E39 540i, 05 E46 330ic, 07 E83 X3 & newest 15 F15 X5.
It's time to drain & fill the X5's Front & Rear Differential fluids. When I go to the BMW Tech site & FCPEuro, they specify the following:
Front Differential with a G2 fluid, which is a GL5 75W85 @ $59.49/ .5 liter
Rear Differential with a G3 fluid, which is a GL5 70W80 @ $80.49/ .5 liter
Both take a little over .5 liter, so I would need to buy 2x .5 liters of each, which is $280 just in gear oil. It's even higher if you purchase from a Dealer.
My question is Why would they (BMW) change from the standard 75W90 GL5 oils? Is there that much difference in these newer fluids?
Why can't I just use a 75W85 GL5 fluid like Red Lines 75W85? It's a good grade GL5 & the same weights as the G2. And why drop the weight to 70W80 for the rear?
Do you think that they have done this to be more GREEN? That would be a better MPG from a lighter fluid OR less harmful chemicals to the environment?
I'm just looking for someone that might know or understand the REAL reason?
Your comments are appreciated.
I own & maintain 5 current BMW's of different years & models (92 E34 535i, 01 E39 540i, 05 E46 330ic, 07 E83 X3 & newest 15 F15 X5.
It's time to drain & fill the X5's Front & Rear Differential fluids. When I go to the BMW Tech site & FCPEuro, they specify the following:
Front Differential with a G2 fluid, which is a GL5 75W85 @ $59.49/ .5 liter
Rear Differential with a G3 fluid, which is a GL5 70W80 @ $80.49/ .5 liter
Both take a little over .5 liter, so I would need to buy 2x .5 liters of each, which is $280 just in gear oil. It's even higher if you purchase from a Dealer.
My question is Why would they (BMW) change from the standard 75W90 GL5 oils? Is there that much difference in these newer fluids?
Why can't I just use a 75W85 GL5 fluid like Red Lines 75W85? It's a good grade GL5 & the same weights as the G2. And why drop the weight to 70W80 for the rear?
Do you think that they have done this to be more GREEN? That would be a better MPG from a lighter fluid OR less harmful chemicals to the environment?
I'm just looking for someone that might know or understand the REAL reason?
Your comments are appreciated.