Can anybody who has actually pulled the above and counted the teeth tell me if this is 21 or 23....short or long too if you know.

There is a lot of conflicting information out there on what will determine the input spline count (e.g., HO vs non-ho, I6 vs I4, auto vs 5spd, model year).

I have a nearly free 231 from a 4cyl YJ lined up, owner thinks its a 23spline, and I'd like to have the right TC in hand before droping mine, laying on my back in my gravel driveway.

87-90 AW4 behind the 4.0 IS a 21 spline (short or long I do not recall). 91 on will be 23 spline, though I wouldn't hold too much confidence in a 91 as it was a changeover year and there might be a few exceptions.

That's what I thought, thanks.

ANybody know what the 4cyl YJ is / could be?

That's what I thought, thanks.

ANybody know what the 4cyl YJ is / could be?

4cylinders are 21 spline