Worn u joints methinks

[Magyver]

In the past few weeks I've been noticing a clunky sound in the rear end area when going into gear especially from park, and thought it was the beginnings of u joints. Lately there has been a slight vibration around 30 on acceleration, and coasting in neutral makes it stop. I don't feel it above 45-50, and no other weird sensations. FWIW I have replaced all tie rod ends, both front wheel bearings in the past year, and the tires are fine. My first thought is still u joints, just a bit worse than before.

My question is this: how far gone are they really? I have a 6 hour road trip coming up Tuesday, and I wanted to get some feedback about whether or not I should drive it ad change out the u joints when I get back, or should I not put those continuous miles on worn parts, risking breakdown? The only time I could possibly do this would be late Monday night but I can't have something go wrong and be too late to rent a car. Second question: what could possible go wrong to make this job go longer than about 2 hours?

 

[smt 59]

Hey Magyver, have you got under the truck and checked for play on the driveshaft? There is a certain amount of play in the rear differential when putting it into gear, as well how many miles are on it and what kind driving do you do? I have not looked at your profile either so is the truck 4wd,mods etc.

 

[Hypnotoad]

They're a biatch to replace. They have nylon pins that need to be torched out. The aftermarket joints have C clips instead, so they're easier to install. Life will be much easier if you have a bench vise too.

 

[Magyver]

Smt--- I haven't actually crawled under yet. I imagine by prying against the yoke and joint I could see play or not. I was asking more about how far to let it go before it becomes a risk of failure. Mileage is 140k, all stock. No off roading, no big tires, no major amounts of towing.

 

[Harpo]

Go on your trip,no worries.
You would feel a lot more rumble if they are really bad,but it's just started you say.
I have never heard of anyone who had a breakdown caused by bad u-joints. You would be annoyed and change them out long before they get dangerous.

 

[smt 59]

I agree, with the low milage and no real abuse it is uncommon for these to go, the rumbling is likely something else and yes I would go on the trip as well with no worries.

 

[nagyiii]

I tried to sqeak every last inch out of mine, and it failed on my in the middle on no where. do the right thing and fix it.

 

[Magyver]

Now I'm back from my trip, about 800 total miles, mostly highway, and the vibration seems to be a little worse but not too much worse, and now there's a new sound. Rather, the same sound that's louder. Not sure if it's rear end gear or u joint, but the link is a video to capture the sound it's making. The first click is reverse, then drive, then reverse, etc

http://i906.photobucket.com/albums/ac266/cableguy2368/Mobile%20Uploads/B266CC19-9DD6-48E4-84D1-A7089A822AA7_zpsscluedhi.mp4

 

[PProph]

that sounds very similar to when my u-joint went a little while back, i posted a couple videos in my thread here (the second video a few posts in has a very similar 'ping' sound when putting into gear):

http://gmtnation.com/forums/topic/8581-drivetrain-noise-video/

If that sounds anything like what yours is, mine ended up being the rear u-joint at the rear dif. it was a pita to change because of those stupid nylon pins, heat and a press are helpful (my propane torch wasn't enough, i had a friend with a shop press and an oxy torch). maybe others have been lucky with less extreme measures but i rarely have that luck and didn't here. good luck!

 

[Magyver]

Yup the noises are the same and i will start with u joints. Thanks everyone!

 

[Hypnotoad]

I was able to do it with a mapp torch.

 

[Magyver]

A late update....changed both front and rear, used MAPP to heat things up, and no problems. The rear joint was toast, all the needle bearings had disintegrated from on side , and the end of the cross was just sloppy in the end cap. My bad for letting it get like that. Anyway, no clunks, popping, squeaking, all is good.

I may have installed the front joint 180 degrees backwards. I marked it, but it came off while handling it. Would that likely be the reason I get a vibration at highways speeds?

 

[Sparky]

Possibly. Typically things like driveshafts are balanced as a unit so if it is installed 180 degrees of how it was it can create a vibe. Spin it back around and see if it helps.

 

[Hypnotoad]

Is it possible the weight fell off?

Flipping it can't hurt, but I have a feeling it won't matter.

 

[Up And Down]

Stumbled across this thread and it may be the noise that I have not been able to isolate and identify yet. Can anyone who has had this noise from their u joints please take a listen to the noise here http://gmtnation.com/forums/topic/11878-help-identifying-a-noise-please/?p=320863 and let me know? My noise is only when turning right and once in a while when going straight. Thanks for the help.