What are the signs of bad u-joints?
 

Hello,

Just out of curiousity, what are the signs of bad universal joints? My truck is approaching 10 years of age with under 90,000 miles on it. Is it a normal scheduled maintenance item after a certain mileage (like a fuel filter)? I notice from time to time, the truck will shake when taking off in first gear. Other than that, the truck drives great.

Cheers,
Dan

just keep them greased, you have to pull them to know if they are actually bad. You can give the driveshaft a sharp twist by hand, if there is a lot of movement (more than 3/8") then your joints are shot.

I'd only use GMB Performance or Precision Machine Ujoints.

Last set that I wore out got to where I'd hear a clank when I started to back up. They didn't seem worn really bad, but new u-joints got rid of the clank.

Thanks for the quick reply. Did a quick check, and there's no movement whatsoever.

Wondered why this post was moved. I thought UV joint symptoms fell into a "general" category. Oh well.

Happy motoring!

Other than the physical check... You'll have a noticable "clank" or "chink" when shifting and going in reverse. And at certain mph you'll feel vibration or shaking.

IF there are ANY visible signs of play in a u-joint, it needs to be replaced

the only thing i have owened that the u-joints went out on was my '73 mach I and they went out every 6 months or so, and i could tell when they were bad. i will try to explain this; when they were bad and you had pressure on the driveline(accelerating or deaccelerating) you could not tell, but if you "costed" the driveline in other words gave it enough gas to take any resistance off the driveline you could feel a vibration and when i felt that i knew my u-joints were bad.

Remember though, the feel of a lil movement inside the truck can be due to the rear end. In manual transmissions, they have a little bit more movement. (this is what i'm told)

Then again, if your like me, your transmission is going. hahah! POS M5OD.

Just make sure that motor mounts and transmission mount are fine.

There will be a little play in the system, for gear backlash in the rear differential, and play in the tailshaft or transfercase.

I've notice sometimes that they will sqeak at low speeds. I have heard mine do that right before they get ready to fail. The way I listen for that is to keep the rear sliding window open and start going slow in first gear. Fred

means you dont greeze em enough fred. :P

I bought lifetime replacement u-joints for my truck. They didn't have grease fittings in them. So I can't grease them. Go figure. Otherwise I would grease them if they had grease zerks.

There are greaseable and non-greaseable types. The only way to know if the joint needs to be replaced is if you get under the truck and grab the two yokes and try to move them around. Look for movement in the joint. I grease mine everytime I change the oil, water gets in there when it rains and wears them out. The joints will usually seem fine, and then all of a sudden eat themselves within a few thousand miles. Most of U-joint failures come from lack of lubrication.

you can always tell when they break..sorry couldn't resist. I have always noticed a "clicking" sound when they are getting bad. if you off-road, you should check them more often because of the extra stresses

oh yeah, and the u-joints for the front driveshaft are interchangeable, so if you ever break a rear one, just take one off the front to get you home