Differential Ratios:

[oliver90owner]

If you cannot read the ratio marked on the diff, jack up one wheel and start counting propshaft turns per road wheel turn. Not difficult to do.

[pgp001]

Are you sure jacking one wheel up will do it ?

I would have thought both wheels need to be free to rotate, otherwise the sun and planet gears in the diff will have the effect of doubling the speed of the one wheel that is free to spin.

Phil

[Bowie69]

Yes, it will double the count, but I am sure you can divide by 2

[pgp001]

The point I was making is that it would really confuse someone who didn't know about that fact.
Not everyone knows how a differential works, especially if they have to ask someone on here

Phil

[Bowie69]

Oh indeed

[oliver90owner]

Far safer to jack up only one wheel. It ensures that the wheels do not rotate at random - one definitely stationary!

One would soon realise that the ratio appears to be not as expected (by those who have no idea how a differential works) so a good learning curve.

I’m sure if he couldn’t work it out for himself, he would ask (but I would be quietly confident that most would soon catch on very quickly when actually carrying out the job )