I've just bought a 3.62 diff off flea bay.It is a push in drive shaft type.Im currently running a 3.92.
I've read on here that the spline numbers and shaft size can change.
So.....how can I check the compatability of my new diff before I take off my existing?
I.e does the main drive shaft diametre have a direct coralation with what fits into the diff?
The last thing I want to do is take it all apart and find I can't put it on.

Also my speedo currently reads about 64 gps to 70 speedo reading.
What effect will the 3.62 have on this giving that the speedo healer hasn't been altered?

Cheers in advance
Danny.

Its pretty easy to take a driveshaft out (wheel off, remove bearing carrier [4 bolts]) pull out driveshaft with bearing carrier.
Then see if it fits into you 'new' diff.

You are right not to take the diff out before you are sure.

by my calcs you should be doing 69mph (GPS) when your speedo reads 70mph.

I've just bought a speedo healer Danny, so got all the destructions if you want to calibrate it correctly.

Cheers Matt,I didn't realize how easy it would be to take the driveshafts out.
I've only had the car one summer so just made the most of it and ragged the poo out of it all the time))
Tee.... If matts calcs are right it'll put my speedo accurate so shouldn't be any need for re calibration.
Just need to get me spanners out and get cracking!!

[Edited on 8/2/14 by danny84]

I just recently swapped my 3.6 diff for a3.9 push in shafts and it was a straight swap.

That's good to know.Hopefully mine will be the same!!