How do you know it's not your driveshaft? I replaced mine with a one piece and all vibration ceased.

 

I replaced all 3 ujoints on the driveshaft in july. Inspected the shaft to confirm it was not bent or out of balance. I have a 2 piece driveshaft.

 

I did exactly the same thing, all joints replaced, no apparent physical damage noted. It fixed nothing. When I replaced the shaft, all vibration went away. I'm betting it's the driveshaft.

 

I would assume that if I brought the truck to a transmission shop, they would be able to tell me if it's the driveshaft. If I had time, I would disconnect the driveshaft from the yoke at the transfer case and recheck for vibration. That would eliminate the driveshaft. I just don't have the time with 3 kids and sports.

 

You'd really need a driveshaft shop as most shops can't seem to test a shaft very accurately. I won't bore you with all the details of what we did to to get to the driveshaft as the problem, but it was expensive and time consuming. Everywhere we looked, we found a problem that needed fixing that we were sure would be it. We never went into the tranny, but everything else connected to it was either repaired, replaced or gone through. The driveshaft was the last resort and the problem the whole time.

 

What I am saying is if I brought it to a transmission shop or the dealership service dept, and they remove the driveshaft from the transfer case and step on the accelerator. If the vibration is there, then it's not the driveshaft or rear axle.

 

That seems reasonable to me. My mechanic said that he'd never had a tranny make that kind of vibration without making some sort of noise, even at idle. That's how we avoided going into it. Those transmissions are pretty bomb proof anyway. I like your idea and look forward to the results.

 

I also look forward to the results, as it is driving me crazy. Someone had suggested that it could possibly be the tourqe converter. What is commonly referred to as tourqe converter shudder. But I definitely want to rule out driveshaft first.

 

Mine did it for years. I was convinced at one point that the tranny was slipping, but the tranny fluid is always clear and that supposedly rules that out. Pretty much everybody complains of this at about 45 mph going up and coming down. Some are worse than others. In my opinion, it's the two piece shaft that causes this. Now that I have a one piece, I feel certain that's the cause.

 

Hey guys I am really enjoying this thread, so much info and i am soaking it up like a sponge. So i am going to throw out a few things and maybe someone could educate me on this, with the above problem of the vibration issue, I have heard that this same vibration could come from the center carrier bearing on the driveshaft, however you have already ruled that out by removing it and testing it. Now here is a off the wall shot, my little bro owns a 03 SD with the 6.0 and had a similar issue as your describing with his truck and honestly thought the tranny was slipping, only to find out that it was an injector which blew my mind. but hey I am still learning, and i know the 6.0s and 6.4 are diffrent in their own rights. So what are your thoughts?

 

My truck has a vibration similar to this and it makes me wonder if an injector could be causing it?

 

my truck did not vibrate .I had new u joints installed and carrier bearing got the truck back and it vibrated real bad took it back they balanced it said it was good still vibrated .I fix it with a hose clamp .I put it by the carrier bearing and balanced it that way and she is smooth sailing ,it's great you have to play with it and I left it kind of loose and it found it's perfect spot.

 

My old 2001 F350 had the same problem, I put new U joints in it and it vibrated. Took the assembly (2 Piece shaft) to a local drive line specialist and they said, greasable U joints are a No NO, installed the OEM type, balanced the shaft as an assembly, no more vibration. FYI when it's balanced as an assembly make sure you mark it if it isn't when you pick it up.