stevepulleyman

How can i determine if its a uk rear diff.
i've one spare and need to clarify that its a uk diff.(classic shape)
if i take the back plate off, how many and which teeth shall i count to determine if its a uk rear diff or not.(or is there an easier way to I.D. it)
thanks if anyone can advise.

911

Easy:
1
Remove oil and end cover exposing the crown wheel.
2
Mark with a white marker pen/tipex a tooth on the crown wheel and on the case closest to that tooth thus giving you a start reference point.
3
Mark similarly the prop shaft flange and case for a start reference point.
4
Turn the prop flange counting the complete 360 degree turns to rotate the crown wheel ONE complete turn and the tipex marks to re-align.
5
You will turn the prop flange about 3 complete turns then a fraction of a turn.
Expect about 3.9 turns (you have to estimate this) for one rotation of the crown wheel.
I cannot remember the UK rear diff ratios off hand, sorry.

little'un

iTrader: (9)

...alternativly, just remove the rear aluminium cover, rotate the diff assy, and just read off the ratio as stamped into the crownwheel

911

So true!

stevepulleyman

Thanks for the advice.

if its a uk rear diff, what should be stamped on the crown wheel, cheers.

911

On the crown wheel side face exposed will be a series of numbers.
You divide the one by the other and it will read something like 3.9 or 3.53 etc. The Jap diffs tend to work out as 1:4.444 or 1:4.111

Not having a UK turbo I am not familiar with the ratio values.

stevepulleyman

Had a look at the stamped numbers on crown wheel.

it reads 39:11, so i presume this is a uk rear diff then ?

911

1:3.54 which i think is a UK turbo diff.

stevepulleyman

so can anyone clarify that a 39:11 stamped on crown wheel is a uk rear diff.