How do you externally identify the diff ratio?

Jack one wheel up, put it in 4th gear & turn the engine over by hand, counting the number of turns to get exactly 1 wheel revolution.

Mark the start points on the wheel & crank pulley first, then you can pro-rata by measuring the the arc length / circumference of the pulley.

Clear as mud?

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Too many cars, and too little time.

no wuckers - all makey cents

no part number method.

The diff ratio is marked on the side of the crown wheel on the bolt head/bearing side with the number of teeth on the crown wheel and the matching pinion. e.g. Cooper S ratio is 18/62 to give 3.44:1.

Don't think you can see it while it's in the car though
Big wheeled Moke ratio should be 4.1 or 4.2:1, but a Morris 1100 unit would be a good swap with their 4.3:1 ratio

Failing that, may be run 10" mags?

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Too many cars, and too little time.

I swopped the 4.267 in my 1275 Californian with a 3.765 and now wish I'd used a 3.444 - plenty of grunt allows easy cruizin' without it screaming it's tits off.
Probably not much chop tho' if your'e into sand dunes or stump pulling..............

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1967 Cooper S - new front bearings to do.
1965 Cooper S shell - Slow progress. No time or money!
1966 Deluxe- next rustoration!
Mk 2 & XJ6 Jags. Less said the better.

Bloke is running the big 998 - screaming is what it does best!

that and the fact it wouldn't be able to hold onto 4th into a slight breeze with a 3.44 diff

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Too many cars, and too little time.

Looks like 98 km.h is all she will do - maybe I should get it registered before I try again

i thought it was on the side of the diff casing