• Forum membership has its advantages....

CV joint service need help (first timer)

dualsport4.3az

New Member
So i had a hole in one of my CV boots. My friend told me that it was not that hard to service them myself, just messy. Taking them off and apart was not hard at all, but while doing some research on the subject, i read that you have to put the axles in the exact orientation they were before. The article said they twist when power is applied to them and thats the reasoning. I know how everything was except the rotation of the axle. Just how important is that? Im running a TomPro Hayabusa sand rail.

Thanks in advance.
 

Wilson

Well-Known Member
That's common practice in the racing world; we have our axles marked so that it's easy for us to re-install them correctly. The same is true of torsion bars, for the same reason. Over time, the bars/axles will develop some rotational offset due to the torque they transmit. The common belief is that once they've developed this offset, they will rapidly fail if used in the opposite orientation. I can't cite any engineering studies to prove it but that's the "tribal knowledge" within the racing community.

Having said that, we only carry one spare axle when we race (and it's "used") - so we live with the possibility that we may have to use it on the "wrong side" (we have done so and went over 500 miles on it at last year's Baja 1000)..... You may be able to determine the orientation in which they were previously installed by examining the wear pattern on the splines carefully. If you can't, just install them without worrying about it and carry a spare.....
 

harleys dad

Well-Known Member
The general rule is make sure the axles themself are put the same way, the cv joints wont care but most all aftermarket axles are torsional so putting the axle the opposite was could maybe have a effect but its not a given they will break. When you put the cvs back on the axle try not to line the holes up from one cv to the other, helps with potential binding. I have done cvs about 10 trillion times in my life and its my unhappiest thing to do. As far as boots if you have clearance a Bates type boots work extreamly good going over the cv joint....good luck
 

matt86m

New Member
Here is a great tutorial about cv's

CV Assembly


As far as the rotation of the axles, ideally you would want to put them back on the same way they came off. More of a worry with higher horse power cars (torque) but still a concern.

If you didn't I would put it back together and ride. but buy a spare - note!!! Measure BOTH axles before you put them back in. Sometimes they are different length's. If they are the same, maybe buy 1 for a spare.
 

43mod

Well-Known Member
the drag cars guys always swapped from side to side to get more life from axles. I wonder who is right or if it really matters.
 
Top