XJ front axle shaft - - do I have big u-joint or small u-joint?

[halmca]

I have an XJ front axle, Dana 30, of unknown year. Need to replace the rider's side axle shaft, but I hear stuff about a large U-joint and small u-joint. How can I tell which I have? Is there a measurement I can take to assure that I shop for the right piece? And, of course, thanks in advance! EDIT: this is a high pinion Dana 30, and it is not a three shaft model.

 

[Rob Mayercik]

Far as I know there's only two sizes: the older/smaller 260 and the later/larger 760. I don't recall when they switched over; I think it was prior to the 1997 refresh, but don't quote me on that.

Have you considered just buying one of each, then simply returning whichever one doesn't match up to what you have now? I don't recall ujoints being that expensive...

 

[IslanderOffRoad]

Measure the bearing cap diameter.

Big: 1.188"
Small 1.062"

 

[halmca]

Measure the bearing cap diameter.

Big: 1.188"
Small 1.062"

Precisely the information I was looking for. THANKS!

 

[halmca]

Far as I know there's only two sizes: the older/smaller 260 and the later/larger 760. I don't recall when they switched over; I think it was prior to the 1997 refresh, but don't quote me on that.

Have you considered just buying one of each, then simply returning whichever one doesn't match up to what you have now? I don't recall ujoints being that expensive...

Thanks. But I'm not looking for a u-joint. I'm looking for an axle shaft. But since information is power, what do the 260 and 760 denote? And a sincere thanks for your information.

 

[RCP Phx]

Thanks. But I'm not looking for a u-joint. I'm looking for an axle shaft. But since information is power, what do the 260 and 760 denote? And a sincere thanks for your information.

Then it doesn't even matter, but as stated the 760 joints have larger trunnions.

 

[halmca]

Then it doesn't even matter, but as stated the 760 joints have larger trunnions.

What doesn't matter and where stated? When you're looking for an axle shaft, you're saying that the OD of the bearing cups doesn't matter?

Or are you saying that it doesn't matter, so long as the replacement shaft, from spline to spline will fit in the axle tube irrespective of whether it has large or small u-joints?

this isn't for academic interest: I am looking to score a used axle shaft and would prefer one that fits my existing Dana 30 on the first try as opposed to paying return shipping to a vendor.

 

[RCP Phx]

Or are you saying that it doesn't matter, so long as the replacement shaft, from spline to spline will fit in the axle tube irrespective of whether it has large or small u-joints?

This!!!

 

[Rob Mayercik]

x2. You can replace the entire shaft of a 260-equipped axle with the whole shaft of a 297/760 one, as far as I know it's a drop-in. Of course, if you're going to do that, it probably makes sense to swap out both sides so you've got the same joint size on both ends.

Also, good source of D30 information is in the FAQ section:

https://www.naxja.org/forum/showthread.php?t=101124

 

[halmca]

x2. You can replace the entire shaft of a 260-equipped axle with the whole shaft of a 297/760 one, as far as I know it's a drop-in. Of course, if you're going to do that, it probably makes sense to swap out both sides so you've got the same joint size on both ends.

Also, good source of D30 information is in the FAQ section:

https://www.naxja.org/forum/showthread.php?t=101124

A most excellent thread, like so many others on this forum. Thanks for the cite.