... go figure. Vibration is back and getting worse. Since this thread was started, I got the driveshaft balanced. That made it almost almost perfect (good enough for me.) A few weeks later, I felt the vibration slowly coming back, so I had him re-do all u-joints. Didn't make a difference. That was in October.

It is now the middle of December and its getting pretty bad. Between 51 and 55, there's a decent rumble and you definitely feel it in the seat of your pants. Above 74 you start to feel it constantly and it gets worse as you speed up.

Where you REALLY notice it is if you're going 68+ and let off the gas. The change in the cupholder literally rattles. It fades away below 65ish. And now, as of today, it feels like the vibration is becoming more constant.

I'm told that it might be the "final bearing" in the transmission. I believe they said toe shaft or something. I'm really at my wits end with this *********g thing. The vibration just won't die.

 

do you have a 2 pc d-shaft? if so , clock the center splines 180 degs. at the carrier brg., It made a world of diff for me. Sounds like the shop may have dropped the shaft or damaged one of the weld flanges by possibly using excess force to get the old ones out. Been there done that. rossford////

 

Nope, 1 piece (2wd truck).

Just got the tailshaft bearing and seal replaced. Made it better, but not great. I can deal with the 53 mph vibration, its the whole shaking like a banshee over 75 that concerns me. Something in my head tells me it could be in the rear end. It has been suggested that I get it on a left (by the body, not the wheels) and run the back tires to see if one starts to vibrate more than the other. I'm going to work on making that happen soon.

 

Two things can be done. First swap tires from front to rear and see if the vibration changes to front, if so then it is the tires/rims.
If that doesn't work then place on jack-stands and with assistant run truck up to vibration speed and check tires/rims, rotation of tires. I had a bent axle shaft.
These two procedures didn't cost any money only a little time to diagnose.

Be Safe,
John

 

Tires have been rotated and balanced since the vibration started. It wouldn't be them anyway as the vibration changes when I let off the accelerator.

My shop is going to get a new driveshaft and yoke and replace both. If that fixes the vibration, then we are going to figure out which one it is and work from there.