Front Axle U Joint Question

[Fish On]

My driver side u joint is done. Truck has just over 60,000 miles on it. I called a local driveline shop and was quoted seven hours of labor to do both sides. The high labor time was due to their requirement to replace the differential seals. They claim that a high percentage will leak if you reinstall shaft without doing the seals. Does anyone have any experience with this claim? Thanks in advance.

 

[mweiman]

I have replaced several sets of u-joints on 3rd gens and they have put many miles on since with no problems. It may be more of an issue on a truck that is 20 years old. If your truck stays fairly clean and the axle tubes aren't full of dirt and rust you should be ok.

Matt

 

[rscurtis]

When I installed the Dynatrac hubs on mine, I had no problem with the differential seals. The bulk of the time may be spent removing the original wheel bearings from their mounts. If it turns out that you do have a leak, then disassembly the second time will be that much easier to replace the seals. If the front axle runs quietly and has no leaks, I would leave it alone rather than disturb the bearings and hope that someone resets the preload and backlash correctly.

 

[Cosmo]

I'm pretty sure I had my driver's side out in under an hour from the time I drove it into the shop.

 

[AMcCormick]

It will all depend on how easy the spindle nut and unit bearings come off. No you should not need to replace the axle seal, just need to be gentle when pulling out and pushing back in the axle.

 

[TimothyLong]

I just had both of mine done along with the ball joints. The shop I took it to charged me for 6 hours labor and that's it (I supplied the parts). They told me the bearings were a serious PITA to get off. They didn't say anything about wanting or having to replace the seals.

 

[DGamelin]

We do this kind of work all the time. We would not replace the seals unless they were leaking or very old like mweiman said. You would have to be very clumsy installing the shafts to have them go bad that often.
We use a pipe that slides over the outer shaft and put a socket in the u-joint so it wont fold over this makes the shaft straight and long easy to handy. Sometimes on real heavy shafts it is a good idea to have help guiding it in. Good luck.

________________________
93 250 2wd xc 354 auto 91k
04. 5 3500 4wd cc dully 373 6speed 136k

 

[04blackcherry]

DG, That's a very good idea. Wish I had thought of that on the 2 I did. The passenger side is the difficult one. I hate the idea of getting dirt inside the diff case. I haven't seen the seal up close but it seems like there is a guiding surface prior to the seal. When reinstalling, the axle seems to find the hole a long way before the splines are engaged.

 

[DBentley]

7 hours labor seems like about right for just the 2 u joints.
It's a bugger of a job on these trucks.

 

[rscurtis]

It took me almost that long to do my truck, with the studs installed in the hubs, the bearings packed, and the U-joints installed in the stub shafts before I started.

 

[TBartlett1]

The reason most seals leak after the u-joints are replaced is because the axle tube gets filled with dirt and crud and someone that is not experienced will just slide the axle in letting it plow thru the dirt & crud that is laying on the bottom or the axle tube, it then gets pushed into the seal & bearing.

I clean the tube using a large fender washer on the end of a broom handle and scrape the dirt out as best I can.

When installing the axle I keep the end of the axle on top of the tube which is clean which avoids pushing dirt into the seal.

I also grease the inner axle end to keep the machined seal surfaces from rusting. I also apply grease liberally to the seal on the inside of the wheel bearing this helps keep water out of the bearing particularly in the North East.

Taking it 1 step further I also clean the wheel bearing OD and the ID of the steering knuckle so the bearing slips easily into place. With everything clean I slather grease on all contact points and also grease the bolts so the wheel bearing or bolts will never ever get stuck again.

Anything I do I clean & prep assuming I will be taking it apart again in the future.

Some swear by never seize but grease has never failed me up here in the North East and I keep my vehicles for many years.

As far as the time goes 7~8 hours sounds about right. It can be a tough job!