Auto with 4.44 [Archive] - 318ti.org forum

yoda

11-03-2008, 06:53 PM

Hello guys,
I'm wondering if I change my open 4.44 diff to a 3.xx LSD would have any adverse effect on the Auto Tranny?

I will do the whole 5 speed swap in the future, but just wondering if this upgrade would be beneficial in the meantime...

Thanks in advance for the responses...:cool:

spidertri

11-03-2008, 07:07 PM

You would be slower off the line but have much better highway fuel mileage. I don't think it would adversely affect the trans, it's just the final drive ratio.

CirrusSR22

11-03-2008, 07:10 PM

I have a 3.45 diff in right now with my auto. Acceleration is slightly worse off the line and cruising on the freeway if quieter. Something like 2400 RPM at 70 mph vs. 3000 RPM. I haven't noticed much of an improvement in MPG. Maybe 1-2 mpg on average. Very minimal.

It doesn't seem to lug the engine/tranmission at all, so I'm not concerned about the auto transmission.