U JOINTS

[Glenn28132]

I replaced my u joints about 2 years ago on my 79
I have seen talk about the brown dust you might see around them I have seen that around mine but they still feel good they are not really tight or any hard spots when i turn them what does the brown dust mean.

thanks

glenn

[Jim T.]

Re: U JOINTS

If the dust is rusty looking, it means lack of lubrication and u-joint replacement is in the future.

[Jim T.]

Re: U JOINTS

If the dust is rusty looking, it means lack of lubrication and u-joint replacement is in the future.

[Joe L.]

Re: U JOINTS

Glenn and Jim-----

Yes, the "brown dust" is usually tiny particles of iron oxide which formerly existed as needle bearings inside the trunnion caps. The "metamorphosis" of the needle bearings to iron oxide is an all-to-common malady which afflicts 63-82 Corvette half shaft u-joints and, to a lesser extent, driveshaft u-joints.

In a 63-82 Corvette, the half shafts serve a dual purpose: they drive the rear wheels AND they are a suspension member. In their latter role, they are "worked" very hard. Their service life is actually a lot shorter than most folks think. In fact, if you were to remove a 1/2 shaft u-joint after as little as 6 months of service and inspect the trunnions, I think that you'd find at least one on each joint which evidences significant brinneling. Essentially, the joint is scrap at this point, but since very few folks remove and inspect their 1/2 shaft u-joints at 6 month intervals (or, usually, any other interval until complete or near complete failure) they just don't know it.

[Joe L.]

Re: U JOINTS

Glenn and Jim-----

Yes, the "brown dust" is usually tiny particles of iron oxide which formerly existed as needle bearings inside the trunnion caps. The "metamorphosis" of the needle bearings to iron oxide is an all-to-common malady which afflicts 63-82 Corvette half shaft u-joints and, to a lesser extent, driveshaft u-joints.

In a 63-82 Corvette, the half shafts serve a dual purpose: they drive the rear wheels AND they are a suspension member. In their latter role, they are "worked" very hard. Their service life is actually a lot shorter than most folks think. In fact, if you were to remove a 1/2 shaft u-joint after as little as 6 months of service and inspect the trunnions, I think that you'd find at least one on each joint which evidences significant brinneling. Essentially, the joint is scrap at this point, but since very few folks remove and inspect their 1/2 shaft u-joints at 6 month intervals (or, usually, any other interval until complete or near complete failure) they just don't know it.

[john lokay]

Re: U JOINTS

Joe, Would rust around my half-shaft u-joint be an indication that the u-joint should be replaceded and potentially be responsible for a squeaking noise I hear when I drive my mid-year at low speed under 25mph?

[john lokay]

Re: U JOINTS

Joe, Would rust around my half-shaft u-joint be an indication that the u-joint should be replaceded and potentially be responsible for a squeaking noise I hear when I drive my mid-year at low speed under 25mph?

[john lokay]

Re: U JOINTS

Joe, Would rust around my half shaft u-joint be an indication that the u-joint should be replaceed and potentially be responsible for a squeaking noise I hear when I drive my mid-year at low speed under 25mph?

[john lokay]

Re: U JOINTS

Joe, Would rust around my half shaft u-joint be an indication that the u-joint should be replaceed and potentially be responsible for a squeaking noise I hear when I drive my mid-year at low speed under 25mph?

[Joe L.]

Re: U JOINTS

John-----

Yes, it could well be. I'm not sure if it's the cause of the squeaking but it does warrant inspection and, likely, replacement of the u-joints. Then, you'll find out if it cures the squeaking or not and you won't have lost anything if it doesn't since, if it's what I expect, the joints need replacing anyway.

[Joe L.]

Re: U JOINTS

John-----

Yes, it could well be. I'm not sure if it's the cause of the squeaking but it does warrant inspection and, likely, replacement of the u-joints. Then, you'll find out if it cures the squeaking or not and you won't have lost anything if it doesn't since, if it's what I expect, the joints need replacing anyway.

[ronnie robertson # 36786]

Re: U JOINTS

Is this a good reason to use replacement U-joints with a grease fitting?
Thanks
Ronnie

[ronnie robertson # 36786]

Re: U JOINTS

Is this a good reason to use replacement U-joints with a grease fitting?
Thanks
Ronnie