Horrible shudder at all speeds when warm, recent driveline work.

Truck starts up and drives fine for about 1/4- 1/2 mile. Then it picks up a horrible shudder that shakes the vehicle until the vehicle stops moving. Clutch in/clutch out is all the same. Engine sounds fine. It will shudder at a crawl and just gets worse with more throttle. The weird part is that it's fine when it's cold.

I did just redo the the u joints and center bearing. The truck is new to me and the old one was shot, but other than some chatter once in a while it was fine. I did have some issues when doing the work. Most notably the U joint at the tranny is 180 deg out of it's original alignment. I also gouged some material out of one of the yokes when trying to press a cup. I cleaned that up with a dremel and still had snug fit up. Obviously, it was a bad day.

While this issue screams drive line, the shudder only happening when warm is odd. I also am trying to figure out what to do next. Wrangling those u joints was a pain I don't want to revisit without cause.

 

I’m just taking a shot in the dark, but I think you’ve identified your issue. Still sounds like driveline to me. The driveshaft might need to be balanced and might still have some u-joint issues.

 

Threw it up on jacks and ran it a bit. It doesn't vibrate much when it's on jacks. Looks like I will need to replace the that cursed front u joint again. Its visibly out of center. It still doesn't answer the mystery of why it only happens after it's warmed up.

 

Clearly the problem. As for why only when warm? Friction=heat. Heat=expansion. Expansion=binding.

 

My thoughts exactly.

 

Did you make the stupid mistake of not marking your driveshaft positions and/or failing to clock the driveshafts during reinstall?

It sounds like a balance issue. Any time you have the driveshaft(s) out, you MUST mark your positions for everything so you reassemble with things in the exact same linear, balanced position they were in prior.

My advice: Find a driveshaft shop. Take the truck in. Explain what you did, and "I think I didn't clock the driveline correctly". As long as you go directly to a driveshaft shop, specifically, and not a bullshit chain store or "generalist" mechanic, they should be able to knock it out in under an hour.

 

This...



Although at this point it may be wisest to just pull the whole shaft and head to the nearest driveline shop

 

"Zerk Orientarion"

 

Yeah I marked all the joints. That's how I know I'm out 180 on that joint. Just was tired and stupid after fighting stick joints all day.
Guess I'll check out a drive line shop.

 

I would flip that one joint. See if it persists. If so, off to the driveshaft shop.

 

well it's better but still far from good. Oh well. Off to the shop.

 

Curious, you didn't install the carrier bearing backwards, did you?

 

I checked the orientation at install, as best I can tell the answer is no. Clipped tabs were installed forwards, but the replacement part was not marked with an orientation. It was a little tight at install, but figured the rubber would sort itself out in pretty quickly.

Checked alignment of shafts and carrier they are about as straight and true as I know how to make them.

It's also possible it's just a bad shaft, and the blown center carrier was both a symptom of that and masking it.

Of course, I may have screwed something up, but it's hard to believe I did it that badly.

Btw anyone have any experience with durashafts? They say it's usa made (though I'm no longer clear if that's a good thing).