[Fot] Spitfire differential - broken pinion teeth

[Tim Pettenati]

Our last race of the season, the CSRG season finale at Thunderhill, didn't go
so 

well.  On the first warm-up session, my wife pulls into the paddock early
and 
says the rear end is making a clunking sound. Turns out the pinion has
two 
broken teeth. Not completely missing, each one lost about 1/3 of the
tooth.

I have a spare stock diff (FC85870) but the axle flanges don't
match. Looks like 

my original diff (FC2669) was upgraded to 1500 bits with
larger flanges, 
bearings, and 7/8" 20 spline shafts.  The rear case must have
been changed also 
to accommodate the larger bearings. I'm assuming all this
was done to fit the 
detroit locker, and heavy duty axles.  Suppose to be
Mother Mueller parts
according to the PO.

So I now have two winter projects -
fix the original diff and upgrade the spare 
so it 

fits.

Anyone familiar
with these changes?

Does the stock 4:11 crown and pinion 510005 work with the
Detroit locker?

Thanks,
Tim