Driveline vibration help

[85-VA]

Afternoon ladies and gents ...
I am having a problem with my driveline... I think. To be more specific, 5 u-joints in 200 miles. I have a severe vibration from 45 to 60 mph. I don't feel it when holding rpm steady in park, so I'm thinking from the converter back. Anyway, 5 u-joints, 4 new tires and rims and a new driveshaft later, I still have no clue. Anyone else run into this issue? Pointers?

I haven't done anything since building the motor last year. This just started and is only getting worse.

1982 C10, 385 stroker, th350 with 1800 converter, 3.73 corporate rear.

 

[73c20jim]

Check pinion angle and other driveshaft angles.

 

[Charlie]

 

[RecklessWOT]

I had this happen on my last '87, ultimately led me to junk a running rust, err I mean truck. There were many issues, it was just the last straw that made me say **** it (though I now kick myself for not holding onto it, would have made a killer parts truck). Make sure your rear yoke isn't ****** up where the u-joint mounts up. ANY play there even if it doesn't seem like a lot will allow it to slop around and destroy the universal in no time. Could have been caused by leaving a bad one in there vibrating for too long, once the yoke itself is damaged it's too late to just replace the u-joint.

Obviously there are many, many things that could cause an unknown vibration, but that's an easy place to check.

Especially with a stall converter, I'd make sure everything behind the transmission hasn't been damaged from being slammed too many times.

 

[85-VA]

Reckless,
Thanks for that. I'm almost to the point of selling this one for scrap. But trying to hang on to it for a street rod/sons truck etc. There is slip in the rear yoke as well as the trans output shaft. In my own stupidity I thought a little slip was normal. Should have known better. I have put it on jack jtands an ran it up to 60mph. Nothing. Seems like the vibration only comes under load, which would make sense. I'll replace the yoke. Which leads to ring and pinion swap. I mean, if I'm in there... Right?

 

[RecklessWOT]

Reckless,
Thanks for that. I'm almost to the point of selling this one for scrap. But trying to hang on to it for a street rod/sons truck etc. There is slip in the rear yoke as well as the trans output shaft. In my own stupidity I thought a little slip was normal. Should have known better. I have put it on jack jtands an ran it up to 60mph. Nothing. Seems like the vibration only comes under load, which would make sense. I'll replace the yoke. Which leads to ring and pinion swap. I mean, if I'm in there... Right?

Well you might be able to rotate it a little and that's normal, but make sure things aren't so beat up that the driveshaft is able to wobble around, should still feel nice and solid even while turning it that little bit. But yeah a real beat up gear set can also cause vibration. If the ring and pinion aren't real worn at least replace the bearings while you're in there, those are more likely to randomly go bad which would also cause a pulsing kind of wobbly vibration like you're describing, and I would suspect those first before the gears themselves anyway.

 

[Arkansas_V8]

Reckless,
Thanks for that. I'm almost to the point of selling this one for scrap. But trying to hang on to it for a street rod/sons truck etc. There is slip in the rear yoke as well as the trans output shaft. In my own stupidity I thought a little slip was normal. Should have known better. I have put it on jack jtands an ran it up to 60mph. Nothing. Seems like the vibration only comes under load, which would make sense. I'll replace the yoke. Which leads to ring and pinion swap. I mean, if I'm in there... Right?

Be either the yoke splines, or pinion to ring gears. If its that. Can't think of much more it could be. New shaft balanced?



Darn @RecklessWOT damn bearings. Didn't even cross my mind. But good one!

 

[Dave 84]

Well check your pinion bearing normally if it was that bad you would have alot of noise.
Put this thing on Jack stands and get it to speed and try to get a visual on it.

 

[henrym]

a slight bend to your rims can cause a vibration, but hopefully the guys who mounted/balanced your new tires paid attention and checked to wobble or ocsillation when spinning the tires., But other than that try some shims between the axle pad and the leaf spring to lessen the angle