LSD Differences between 901, 911 and 915 Gearboxes.

[Rob B]

Are there any differences in the LSD required to fit into an aluminium 901, magnesium 901/911 and 915 gearboxe?
I currently have a 915 gearbox with LSD in a 1969 car that I have to swap out with a 901 or 911 box to meet class regulations.
Can I swap the LSD from the 915 into a 901 or 911 box and use the flanges and driveshafts currently on the car? If so would it matter if the box was an earlier aluminium 901 or later magnesium 901/911?

Rob

[edmayo]

Its been awhile since I did a similar install, but I believe your currant LSD would fit better in the mag 911 box than the aluminum 901 housing. I seem to think I did the opposite, put a 901 unit into a mag box and I think it required an additional 6mm of shims to fit the housing, that's in addition to the normal shimming required for the carrier set -up. I'm sure you realize that you will need to do the entire carrier and pinion set-up again. I'm not positive my memory is correct, hopefully someone else will jump in here!

[kenikh]

Here's a start:

http://www.early911sregistry.org/for...d-901-trannies

[Jon B]

Can I swap the LSD from the 915 into a 901 or 911 box and use the flanges and driveshafts currently on the car? If so would it matter if the box was an earlier aluminium 901 or later magnesium 901/911?

The 915 diff will not work in a 901 aluminum transmission housing. Several dimensions are larger, and roller bearings are larger. It will work in a '69-'71 901/911 magnesium housing, although the '70-'71 is arranged for a pull-clutch.

Jon B.
Vista, CA

[gled49]

+1 with Jon B. Also as a correction Alu trans ZF 901 LSD's are all the same, only the drive flanges are different, Nadella vs Lobro. Gled