Ujoint replacement.

Diffs, axles, lockers, transmissions, portals, that kind of thing.
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Twin Pinzies
Posts: 545
Joined: Mon Jan 03, 2005 1:33 pm
Location: San Juan Mountains, CO

Ujoint replacement.

Post by Twin Pinzies »

My ujoints are needing to be replaced. Any tips from you guys that have done it?
steyr92
Austria
Posts: 19
Joined: Tue May 22, 2018 1:40 pm

Re: Ujoint replacement.

Post by steyr92 »

i´ve done it 2 month ago.
got the u joint from gkn , part number u742. all in all pretty straight forward
mark the driveshaft teeth to the tube and also the flanges.
i replaced it with the hammer method and vice method. pretty straight forward to youtube videos.
also check(mayby if still installed) if there is any play in the shaft when you grab it in the teeth area and push it up and down. i had the case so i needed to replace the whole shaft ://
when ujoints are changed, check that movement is not too tight, and prelube them and check that greas purge out equaly on the bearings. i lubed mine every 20 km in the beginning until no more grey, contaminated grease comes out. now they run perfect.
greets
stiffler4444
Canada
Posts: 776
Joined: Mon Mar 15, 2010 1:46 pm
Location: Crystal Beach ON CAN

Re: Ujoint replacement.

Post by stiffler4444 »

I had a bit of trouble with mine. Most notably, not all shafts take the same size ujoint. I ordered some fro EI and they didn't fit. I thought it was an oddball drive shaft, so I bought a spare one and discovered that the ujoints didn't fit that one either. It drove me crazy trying to figure it all out. At the end of the day I just used the joints from the second shaft that I bought. Hope you have a better experience!
1972 710m
steyr92
Austria
Posts: 19
Joined: Tue May 22, 2018 1:40 pm

Re: Ujoint replacement.

Post by steyr92 »

you can measure them pretty easy when dismounted to be sure. bearing cap diameter, crosswidth and place of the greasefitting.
stiffler4444
Canada
Posts: 776
Joined: Mon Mar 15, 2010 1:46 pm
Location: Crystal Beach ON CAN

Re: Ujoint replacement.

Post by stiffler4444 »

steyr92 wrote: Tue Jun 12, 2018 7:40 pm you can measure them pretty easy when dismounted to be sure. bearing cap diameter, crosswidth and place of the greasefitting.
I did all that and even from a specialty drivetrain shop couldn't get any to fit mine. So strange. I had presumed that ones from EI would fit even before I measured. That was not the case.
Do you happen recall what the measurement was on your shaft? I'd be curious if it's the same as mine or different.
1972 710m
steyr92
Austria
Posts: 19
Joined: Tue May 22, 2018 1:40 pm

Re: Ujoint replacement.

Post by steyr92 »

i only measured the ujoint itself after dismounting and comparing to some info in the internet(hard to find) and got 81.8mm width and 30mm cap diameter which is exactly the gkn u742
plug n play in my case
stiffler4444
Canada
Posts: 776
Joined: Mon Mar 15, 2010 1:46 pm
Location: Crystal Beach ON CAN

Re: Ujoint replacement.

Post by stiffler4444 »

Ya, mine was in the mid 30's, have to look back. Odd there'd be different sizes.
1972 710m
steyr92
Austria
Posts: 19
Joined: Tue May 22, 2018 1:40 pm

Re: Ujoint replacement.

Post by steyr92 »

you sure that its an originsl shaft?
stiffler4444
Canada
Posts: 776
Joined: Mon Mar 15, 2010 1:46 pm
Location: Crystal Beach ON CAN

Re: Ujoint replacement.

Post by stiffler4444 »

Pretty sure given the ujoints that were intact were obsolete European units. The second shaft I bought from the same dealer was slightly different, but I would imagine suppliers changed throughout the run during the years. After buying the second "OEM" shaft, it was a different size as well. I'm going to measure up both cap diameters and post up. I suffered no end of frustration and threw a way some cash trying to solve this issue and it has scarred me permanently. :((
1972 710m
Twin Pinzies
Posts: 545
Joined: Mon Jan 03, 2005 1:33 pm
Location: San Juan Mountains, CO

Re: Ujoint replacement.

Post by Twin Pinzies »

Thanks gentlemen. I guess that I'll just drop it by my mechanic rather than risk being stuck with a truck that can't drive,
Twin Pinzies
Posts: 545
Joined: Mon Jan 03, 2005 1:33 pm
Location: San Juan Mountains, CO

Re: Ujoint replacement.

Post by Twin Pinzies »

UPDATE:
I'm glad that I chose to take it to my trusted mechanic...

The old u-joints were quite hard to press out of the flange without bending anything. Then one of the new u-joints didn't fit into one of the flanges without some small grinding of both the u-joint body and the flange.
The part numbers were identical (from SAV) and the driveshaft was original to the truck, but somehow, one u-joint fit right in and one didn't.

Since Pinzgauer driveshafts and universal joints aren't "live" and therefore don't ever flex, they just wear a notch in the one fixed angle/position that they are set at. Which is why they wear weirdly in just one spot.

A few of the needle bearings were dry and almost completely gone even though I've been pretty diligent about keeping them greased over the past 13 years.
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