General Tech Universal Joint—Driveshaft

[KVH]

Can I replace a drive shaft universal joint with the driveshaft left in the car? Room is tight but it must be possible?

 

[PAUL161]

You might want to pull the whole shaft out and put it on the bench, makes life a lot easier! PJ

 

[KVH]

Can I do that without removing the transmission?

 

[bobhustead]

Removal of transmission is not required. The drive shaft ends terminate in 4 -bolt flanges that unbolt from similar flanges on the tranny and rear end.
Bob

 

[charleyf]

I would not try to replace the U joint in the car. ( You should likely do both front and rear at the same time.) It requires a lot more need of movement than you are apparently aware of..
Charley

 

[Geo Hahn]

Really takes very little time to remove the propshaft completely. I did it recently just to have more room to replace the rear seal with the gearbox in the car.

Once undone on each end it is easily slid out the back .

I always mark the flanges so I put it back in the exact same orientation but not sure that's necessary.

 

[CJD]

Not really. You cannot access the front of the drive shaft in the car. Then, as mentioned above, it's not really a job to replace u joints in tight spaces.

 

[bobhustead]

And as long as you don't take the splined yoke apart, you don't have to mark the position of any components.
Bob

 

[KVH]

Oh? And what fate have I invited by failing to mark that yoke? It’s all back together, and I guessed

 

[DrEntropy]

Oh? And what fate have I invited by failing to mark that yoke? It’s all back together, and I guessed

The driveshaft is spun up to balance it when first assembled. You may experience a vibration if the yoke alignment is off from original position. Any good driveshaft shop should be able to rebalance it, just tell them you may have the weight distribution off and why.

 

[bobhustead]

If you put it back together with both u-joint yokes in the same clock position, you are 50/50 likely to have it in original position. Even if you are out 180, you may very well not get a vibration. If you do, try a 180 position change before the shop.
Bob

 

[DrEntropy]

Actually there are four possible ways to line up the U-joints. Two with yokes on each end the same and two not so much.

 

[LarryK]

I have got them jacked up high enough to run and hold a marker to the driveshaft and see if it vibrates and used ss hose clamps and balanced them. Not for the unsafe person.

 

[KVH]

Is this a big enough issue that I need to pull the driveshaft and have it balanced, or is there sufficient working space underneath to release and change the yoke spline alignment after a few test drives, or successively?

 

[charleyf]

Is this a big enough issue that I need to pull the driveshaft and have it balanced, or is there sufficient working space underneath to release and change the yoke spline alignment after a few test drives, or successively?

I have replaced the U joints on 4 TRs and have yet to have any of the drivelines balanced. And have not felt any vibrations.
Charley

 

[KVH]

Great. I’ll put it all back together and report by post if I feel or hear anything I don’t like or can’t recognize.

 

[mezy]

I have change many many UJ's during my lifetime without the need to rebalance a prop shaft,
I have even shortened propshafts without rebalancing, allways shortened them at the yoke and never had an issue

 

[PAUL161]

I've replaced a "few" U joints also and never had to have one balanced. Only when I've had a driveshaft shortened, or lengthened, they were balanced by the driveshaft shop.

 

[LarryK]

Align UJs as they came out and you should not have problems. Only time I had to balance was for length, shortening, or replacing damaged yokes from crashes or failures.

 

[CJD]

Yes, run it. If it vibrates, then have it balanced.