I posted this in the Alberta section, as a reply to a thread, but felt its worthy to start its own thread.

as a courior, I seem to eat thru a few U-joints, in particular the Precision brand, I'm on my 3rd Joint in 3yrs (same side) and have only gone 175,000kms in that time frame.
I noticed this when I installed it last time, that it has a plastic "plate" at the end of each cross shaft and a tiny hole to allow grease to lub the needle bearings.

Here is what I posted in the Alberta section:

Here is a pic of a U-joint I replace this morning (took an hour start to finish)
It is a precision joint, Made in the USA, all the "nozzles" were plugged, so it actually never got any grease, and I greased it every month or so.
I actually shot grease in it as the pic shows and only one nozzel shot a little tiny stream of grease,. I dont understand the reasoning behind theses nossels, I drilled one out and shot grease thru it and look at the difference, I think if I installed one of these type again I would drill it out first.

the China brand I installed today has huge hole drilled in the end, and does not have the plastic plate on the end of it, its steel on steel

this is what it looked like when I removed it, all cups were dry and starting to gall/sieze


here is a close up of the plugged ends


here is a grease gun hooked to it and I had a hard time to get the grease to "pop" out


here is what the end looks like after the crap is cleaned out of the end


here is what it looks like with the hole drilled out


and here is how much more grease will pass after drilling out the nossel, no chance of this hole plugging up

 

I always use non-greaseable joints on the trucks I work on.
None have failed under 100k miles.

 

i agree, it's hard to beat oem non-grease able u joints ....i know 2wd drive line u joints don't have the motion 4wd have.
but i have 230k on my joints, no sign of them going bad

 

Yeah. After a thorough discussion with a number of guys who know, I went with the factory sealed Spicers. 85K Miles is a reasonable lifespan for these IMO. And the solids are stronger than the greasables.

Kurt

 

I had the same problems with the percision brand. No more for me. Installed Spicer joints and haven't touched em since

 

I don't think it matters as long as you grease the U-Joints regularly and not leave them to dry up. We use more grease able than sealed at our work and they hold fine. JMO

 

that was the problem, I greased it at least once a month, except the grease never made it to the u-joint cups! I'm going to go with the non greaseable ones next time...unless this "cheap" joint I have in there now holds up.
I blame the plastic nossels for the grease failure, to make it to the cups

 

What symptoms are you guys getting when the u-joints go bad? Is it the little binding noise?

 

I've always replaced U-joints with Dana/Spicer parts and have never had a problem. I do like how you hogged out the holes to prevent blockage in those Precision Joints...good thinking.

 

binding/clunking/squeaking/vibration are all symptoms, dead give away of a failing joint is any rust colored dust near the u-joint.

 

thx for the pics. I think i wont buy a precision joint after seeing the pics. also, so far the brute force joints have treated me pretty good.

 

Its best to inspect them at oil change intervals. I have 120000 on the originals and they are ok still. Failure starts off with a squeak or a distinctive TING as load is applied. It can be heard taking off from a stop or sometimes just dropping into gear. Once it gets to binding, grinding or vibrating you will be walking soon. Driveshaft angle has a direct impact on U joint life more than most other factors. Lifted trucks will have u joint disease just like an overweight person has joint disease. Ive seen some so extreme that when the truck gets air on a bump the yokes bind up and tear them out quick. Pinion angle can be adjusted with wedges but that doesnt resolve the problem at the transfer case completely. On a front axle, rolling the pinion up to reduce shaft angle changes caster. Its a tricky business and it will get your mind to working for sure.

 

nickg,
Excellent article on u-joint failure.I've changed many of these over the years and, as you say ,the cups are always dry and rusty, a good sign no grease was getting to the cups.I only have 86K on my truck and haven't had any u-joint failures yet but when I do , I'll drill the ends out as you did. Thanks for the idea!

 

Well, I tend to sealed joints as well because I am horrible about greasing them, but when I have greasable ones I always make sure to put in enough grease to see something come out- water , oil, or grease. You have to push the contaminants out or the new grease will do little.
That's something I find a lot of others do not do- they only grease until there is slight pressure resistance. How do you know what is causing the resistance?
I've been told I an breaking the seals by over greasing- but since I am pushing out contaminants (most often water) I'm ok with breaking the seal to be sure grease is where it needs to be.

 

The problem I have with greasable u-joints is even if you add enough grease for it to squirt out the seals it often only comes out one or two of them.
On my farm equipment PTO driveshafts I've paid attention and it's usually the same couple of seals that the grease exits.
Sometimes you can get it to exit from different seals by rotating the joint while greasing but it doesn't happen often.
After a joint failure when disassembling the joint it seems there are always a couple of bearings filled with hard dried grease...