Maybe you guys can help.

I was coming home the other night and though that I had lost a U-joint.

My truck was shaking really bad from each stop light. I checked all the U-joints and the carrier bearing and all is good. Thats a bummer...U-joints are cheap. No shake on coast or cruise just acceleration

Im guessing I lost an injector.

Im guessing the VE pump wont loose just one cylinder. Is that right? How do they fail? Do they just get weak over time?

My truck is a 5sp 4x4 with about 210k on it and all stock. Probably time for some injectors and a pump rebuild anyway.

thanks

 

That may be possible but here's some thing you should check first!
a bad u-joint could be a tight u-joint. you can't tell by getting under the truck and feeling them, you got to pull them from the truck!
If the shake is only when taking off from a stop light then i would guess a stiff u-joint or maybe the slip yoke or evan possible the carrier bearing......if it is a 2 piece drive line!

 

This is a long shot, but check motor mounts and tranny mounts. Sometimes they will tear, I've never checked mine or heard of it tearing from a cummins. Checking is cheap! (These trucks do have rubber motor mounts, Don't they?)

 

I dont think you lost an injector- you wouldnt have made it home. But can you rev it in neutral and not shake? Or is the shaking just when moving? If it's only when moving, I tend to agree with flashgordon- check your driveline.

DP

 

Thanks for all the input!

The way it was shaking a U-joint would have been toast.

I will check all my mounts again but that was on my mind and I would have expected to see my gearshift (5sp) moving around. With a shifter that long and broken engine mount, I'd have a black eye!

If you guys dont think an injector could cause a shake that bad., Im back to suspecting the carrier bearing. That rubber is 14yrs old. Probably worth replacing anyway.

How doe the VE pumps fail? Can you loose one cylinder or do they just get weak across the board?

 

The pump usually just stops pumping...at least in my experience I'd concentrate on the driveline and maybe the countershaft bearings in the tranny...

 

A u joint that is starting to seize will do it. Pull the driveshaft and move them through the normal range, if you have a bad one you will feel it. A carrier bearing would make a lot of noise and an injector should make it idle rough and or smoke puffs at idle.

 

I have seen u joint failure that you needed to put the truck from D to R and use heavy gas and brake to see the buggers fault, sometimes they will be bad, and no amount of HUMAN arm power will reveal it, Look for reddish coating aroung cups, or a blueing of the steel may be your only way to tell without tearing apart
On a side note, I use a non contact thermometer once or twice a year on all the ujoints and bearings/brakes, I will be on the highway for some time, I pull over and check the temps, It is amazing what temp will tell you, and how much $ it can save you, I have had ujoints 50* hotter than others, and found that they will be bad in a year,
Peter.