Any idea what would cause this type of U joint bearing wear? I had my driveshaft shortened, and new yolk installed, and new joints, then balanced, all at a reputable driveshaft shop. I have 2500 miles on this U joint. It is the rear joint. I replaced both front and rear ones after seeing this, and it did not correct the shake. I feel this damage is more the result of the shake, and not the cause, but am looking for suggestions. I have a whole vehicle shake at 60 mph, so I ; Put it on jack stands, and ran it to 60 = shake still there Removed rear tires and ran it to 60 = shake still there pulled the driveshaft and found this... if it makes a difference it is a AOD trans and a 8 inch ford rear end.
Also, It sounds like the driveshaft is warped, bent, end welded on wrong or just plain wasn't balanced.
Are both ends of the driveshaft phased correctly, meaning are the yokes in line? How much angle is there at the u-joints, and are both exactly the same?
Sounds like you have been troubleshooting this before! I assume that the u joints were cleaned for the pictures and it wasn't missing any roller bearings. Any yoke damage or loose pinion/ pinion bearings? Pinion angle is checked and ok? How is the drive shaft angle? I know drive shafts /driven shafts are ok in the same plane (parallel) but need to have a angle in the drive shaft itself. Did the vibration problem cause the irregular bearing wear or the failed u joint cause the shake? You didn't say if you run the car hard and if it's a hotrod? Could you have twisted the drive shaft. Check it out and maybe have the guys that did the balance work check the drive shaft to eliminate it as the problem. Good luck-
I'd say so too, look at the damage; it's where you'd expect it to be if the caps were warped by overtorque... Not on the "sides", just damage on the "front and back" (as much as a cylinder has sides).
Jack stands should have been under axle so rear end is in same position as when on ground. 60 is ok on stands my question first off is what are your drive shaft angles? Lets start there.
Yep, I have seen that before. Every time I overtightend the u-bolts on my Jeep and then went wheeling, the trunions looked like that or worse. Sometimes, there was just metal slush where the needle bearings were. It is surprisingly easy to overtighten u-joint u-bolts. Good thing they are cheap.
check the yoke on the diff to see if there is any wear /where the cups ride and if it is new check drive shaft for being stright and yokes in alignment both dynamic and lateral
I'll pile on with the overtorqued u-bolt. That type of wear on the cross is called brinelling. The torque spec is around 20 ft-lb, which isn't much. Easy to overdo if you didn't use a torque wrench.
If that wear is only on the caps that are retained by the U bolts I would tend to agree that they were either over tightened or not correctly seated in the yoke. That type of brinneling can also be caused by not enough angle in the driveshaft. But will normally be present on all 4 trunions. I would however take everything back to the shop for a re-check just in case.
What lo-buk said..........I'd look at the driveline angle first, that'll cause vibration and u-joint wear as well. You can over torque the hell out of the hardware but it shouldn't create any kind of driveline shake until the joint turns to paste.
WOW, a wealth of info, here is what I know yes run at 60mph on jackstands, and yes it was facing out of the garage with the door open yes, this joint was cleaned for the photo, it was fully greased and all needle bearings intact. it is a street rod, not a drag racer. Stock 5.0 ford EFI trans angle down 3 degrees, axle angle up 2 degrees. the damaged surfaces are the ones from the yoke on the rear axle, that are attached with the u-bolt retainers. I have only hand tightened them with a small box end wrench, cannot get a socket and/or torque wrench to it. I did check (after finding the damaged joint) to see it the yolk is square, and it checks out. the front U joint did not show any signs of damage, but I did replace it at the same time as the rear (cheap insurance) I think I need to hae the shaft rebalanced, but am still open to your suggestions
Never ever saw a U bolt that would over tighten a cup to do that much damage to a trunion not saying it couldnt happen but not likely. Cups are tempered. Now according to your figures you only have 1 degree of pinion angle-I would check it with the weight of the car on it as if it was on the ground on all 4 wheels. I would go at least 3degrees of pinion angle. Next I would put it on stands and check out the shaft for straightness. Get a big screw driver and let it run on stands just over an idle in gear and use the screw driver as a tramal rod and check the shaft front-middle and rear for run out. Your problem really seems to be in the driveshaft.
Well, I wrecked another U-joint.... It looked just like the damage I had on my other joint, so I decided to do a bunch of diag, and checking out of everything. When it is installed it looked correct. But it you take the u-bolt off, and just pull the driveshaft bad a smidge, it shows that the yoke has a bigger hole than the bearing cap, but about 1/16th of an inch. After working with Mike at DTS, we checked and cross referenced everyting and found a joint with different sized caps, and the correct width. Fits like a glove.... put it all together this afternoon, and went for a drive. no more shake go figure, the 8 inch in my coupe has a bigger yoke that the 9 inch in my sedan.....
I was going through the post from the first one and new the answer the dumb 8" ford sometimes have this dumb joint I think Mavericks had them. Driveshaft cups are 1-1/16 pig yoke has 1-1/8.I have one in my 34 ford.Had guy with Willys with 9" same thing but he raced his went through joints every month.When you tighten the joint I think it egg shapes the cup and then doesnt roll.
1-5349 naepco is the right joint for a 1310 (1 1/16 x3 7/32")gm to a big ford 1 1/8 cap x3 5/8".I use them all the time $20.00 at speedways .
I think not enough angle on driveshaft. I have similar wear on pto shaft joints used in straight line setups. A little angle is a good thing.
Good find! Surprised you didn't run into it sooner since all the parts you have there are so clean. I used to take my measurements and even the drive shaft to a local friendly parts house and go through his catalogs until I had what I needed. Bob
this might be what I was looking for.....nothing better than heading home after a 3 day race and have u joint issues ....especially when you only an hour and half away from home....
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