3aj gearboxes

**Alfow** · #1 27 Jan 2007

I've read that 88 and 89 3aj gearboxes have different demultiplication systems between 88 and 89 with the 89 one being better. I have an UK registered F reg which is 1988/1989. Can I tell from the engine /frame numbers if I have the later version? If so what am I looking for? Many thanks

**okrad** · #2 27 Jan 2007

didn't want to start the new thread since it's a similar problem.
first, what does the 'different demultiplication systems' means?
second, i have a 1990 3AJ with busted gearbox. something has come off of something and made a chaos in it, resulting with 5-6 busted gears

.
so, i've found good used gearbox from another 3AJ, so i've been told, but there is something wrong. this one is diferent. where the first axle goes into clutch, it has 6 nuts/gears and mine has 14 or so. also, where second axle goes into chain gear, it has also 6 nuts/gears and mine has 15-20 or so. other than that, they are identical.
so, i' ve been looking for what to do, and i think i should put new gears onto mine old axles. but what is the procedure to remove 2 speed gear from first axle? is it on cone, or do i need a press to remove it?
also, what models are those two gearboxes that i now have?
thanx, an sorry for bad english

**aukeboss** · #3 28 Jan 2007

meaning, I think the ratios in the g'box. They have indeed been chaged slightly between 1VJ, 3AJ mark I and 3AJ mark II models. However, as far as I know all the rest (clutch, output shaft and input shaft) have not been changed. Except for the connection between front sprocket and output shaft, the newer models, starting with 1VJ, have fine splines and a big nut. The older types have 8 or so splines, two bolts and a plate to fix the sprocket to the shaft.
So, think you have been sh*fted with the new gearbox.

To remove the gearwheel you need a press. Once you have one, easy work.

Auke

**okrad** · #4 28 Jan 2007

thanx Auke,

Quote:

Originally Posted by aukeboss

So, think you have been sh*fted with the new gearbox.

damn! well, anyways, new gears are better from old ones(not broken), and they have identical number of teeth?, so i'm puting them.

also, i'm just swiching gears onto my shaft, using press to remove 2 speed gear and there's nothing there? i expected some small nuts or something...

cheers