Need U-Joint advice

[Tim L.]

Discovered a new noise while taking the car for it's first spin the spring. Sounds like a u-joint. The drive shaft has zerks on both ends. I was able to grease the front one but was unable to service the rear. The half-shafts do not have zerks. Question is: since there are 6 u-joints how do I go about figuring out which one(s) is causing the problem? By visual inspection they look fine. Or do I have to tear into it and replace all of them? Or is there something else I'm overlooking?

It's a 66 small block with 4-speed.

Thanks for any advise!
Tim

[Kenneth T.]

Re: Need U-Joint advice

Most of this you probably already know, but. If you have access to a lift, get the car off of the ground put it in neutral and get hold of a stethoscope and place the wand on each joint and have someone rotate the rear wheels, check each joint one by one.

The click and squeek will be the bad one. A long thin screwdriver can be useful if you cannot locate a stethoscope. Also, grab the drive and shafts and try to gain movement up, down, whatever any of that will also be a clue to wear.

Ken

[Dana M.]

Re: Need U-Joint advice

Sometimes you can find the bad one just by looking. Look for a red rust dust around the main body of the u-joint coming out of the cap. You can't beat the feel test by taking out the halfshaft and working the u-joints. My theory is if one is bad, change all 4 and save down time later.

[Joe L.]

Re: Need U-Joint advice

Discovered a new noise while taking the car for it's first spin the spring. Sounds like a u-joint. The drive shaft has zerks on both ends. I was able to grease the front one but was unable to service the rear. The half-shafts do not have zerks. Question is: since there are 6 u-joints how do I go about figuring out which one(s) is causing the problem? By visual inspection they look fine. Or do I have to tear into it and replace all of them? Or is there something else I'm overlooking?

It's a 66 small block with 4-speed.

Thanks for any advise!
Tim

Tim-----


If you have one that's bad, it's extremely likely that you'll have more in the near future. There's no sense in just doing the bad one. What you're almost certainly going to find is that ALL of the u-joints are bad---there's just one that's a lot worse than the others.

When you get the shafts out, if you inspect the trunnion bearing surfaces (i.e. the surfaces where the roller bearings contact) you're going to find brinnelling. Just a slight amount of this on any of the 4 trunnions and the joint is not suitable for re-use.

I would not recommend that you attempt to replace the u-joints yourself. Take them to a driveline shop with experience. The half shafts can be very difficult and special procedures are necessary. The driveshaft joints are much easier, but the driveshaft needs to be balanced after u-joint replacement. So, all-in-all, you're better off to take all the shafts to a pro. It's usually not even all that expensive, either.

[Tim L.]

Re: Need U-Joint advice

Thanks for the pointers Ken and Dana.

Joe - makes sense to replace them all. Looks like I'll start looking for a good place to have it done at.

Tim

[Joe L.]

Re: Need U-Joint advice

Thanks for the pointers Ken and Dana.

Joe - makes sense to replace them all. Looks like I'll start looking for a good place to have it done at.

Tim

Tim-----


If you live in any kind of metropolitan area there should be at least one driveline shop. These days, most of their business comes from trucks and industrial machinery. But, they do car stuff, too. Look for one that is named "Driveline Service of XXXXXX" with the XXXXX being a city name. I believe these were once connected to Dana Spicer but I don't think they are anymore. But, they're usually very competent and they use only quality parts.

[Tim L.]

Re: Need U-Joint advice

Tim-----


If you live in any kind of metropolitan area there should be at least one driveline shop. These days, most of their business comes from trucks and industrial machinery. But, they do car stuff, too. Look for one that is named "Driveline Service of XXXXXX" with the XXXXX being a city name. I believe these were once connected to Dana Spicer but I don't think they are anymore. But, they're usually very competent and they use only quality parts.

Joe

That's one of my problems is I don't live in a big city. If I can find a place locally, do you suggest removing the drive shaft and half shafts and taking the shafts to them for repair? Is removal a difficult operation? I can do alot of things, but I have never ventured into C2 rear suspension before! Or is removing and installing best left to professionals?
Thanks for your help.
Tim

[Gary R.]

Re: Need U-Joint advice

If you decide you want to do them, burn them out and use a plate to bolt the flange to. Use Spicer solid joints as well.
Here is a link to a thread I wrote on the job,maybe it will help you.
Good luck

http://www.digitalcorvettes.com/forums/showthread.php?t=76752

[Jim T.]

Re: Need U-Joint advice

Tim you said it sounds like a u-joint. Is the noise constant straight line driving, or only when turning?
Do you know when your rear wheel bearings were serviced/repacked with new grease?

[Tim L.]

Re: Need U-Joint advice

Tim you said it sounds like a u-joint. Is the noise constant straight line driving, or only when turning?
Do you know when your rear wheel bearings were serviced/repacked with new grease?

Jim -
The noise is not constant straight or turning. It comes and goes when I'm giving it some gas. It stops when I back off.

I do not know when the rear wheel bearings were serviced. Wouldn't the noise be contant if it was a bearing going out?

Thanks for your suggestions.
Tim

[Steve L.]

Re: Need U-Joint advice

Joe,
How important is it to balance the main driveshaft after U joints have been installed?

[Jim T.]

Re: Need U-Joint advice

Tim I don't really have enough experience to comment on what your actual noise is from.
Replaced a u-joint in my 68's right half shaft in 1977 when it made a noise when turning a corner, inspection showed me which one it was, the red dust that has already been mentioned.
The right rear wheel on my 70 actually locked up SEP 1978 after I paid a Corvette garage mechanic to service the wheel bearings in June 1978, about 4,000 miles later. Had no indication that there was a problem. Left the car sitting for hours to cool down and was able to drive it a couple miles home. I bought the service manual tools from KM and have done my own rear spindle bearing servicing since that experience.
Several posts here for help on your problem. Let us know what the discovered problem is.

[Joe L.]

Re: Need U-Joint advice

Joe,
How important is it to balance the main driveshaft after U joints have been installed?

Steve-----


Personally, I would never install new u-joints on the driveshaft without having the complete assembly subsequently balanced.

[Tim L.]

Re: Need U-Joint advice

Examined the u-joints on the half shafts again over the weekend and did see indication of the red dust on one. I think I'm going to pull both half shafts and replace all four u-joints. Getting the shafts out doesn't look like it is that major of a job. I have a place I can take them to get the new u-joints installed. Are the u-joints from Long Island the best route to go with for judging?
Thanks to all who have replyed.
Tim

[John H.]

Re: Need U-Joint advice

I have a place I can take them to get the new u-joints installed. Are the u-joints from Long Island the best route to go with for judging?
Thanks to all who have replyed.
Tim

I don't know what LICS is selling, but what you want is Spicer joints with no grease zerks. Make sure the shop you use knows that replacing the outboard U-joints requires a spare flange or steel plate bolted to the existing flange to avoid bending it while replacing the joints, or you get to spend sixty bucks per side for new flanges. If they don't know that, go elsewhere.