New tubes, ujoints and carrier and shudder still at 20mph.
I really thought the Ujoints would do it but they didn't do it all.
Can someone tell me how the phasing should be on this truck?
Do the end yokes at the transmission and the rear end have to be in the same phase? I'm beginning to wonder if when they did the new tubes on my driveshaft that maybe they didn't weld them up at the correct timing.
Anyone that knows anything about this please let me know. Dealer is useless and just keeps trying different fixes that make the truck worse. They want me to shimm it but it never needed this before they did the carrier and the new tubes on the shaft. I went from having a slight vibration at 75mph to one at 20 and 40 and 75 to one just at 20 now...:mad: Can anyone shine some light on this mess or know someone that could?

Phasing is used on drive lines that require multiple drive shafts . If you have only one drive shaft from the transmission to the rear differential it will not be required .

Phasing is used on drive lines that require multiple drive shafts . If you have only one drive shaft from the transmission to the rear differential it will not be required .

I have a 2 piece driveshaft. I just got under my truck and looked and the end yoke out of the tranny and the end yoke on the rear end are not aligned. From what I've been reading they are supposed to be but I'm not sure if GM did it this way to cancel out some other vibration. The dealer had a driveline shop put new tubes on and that's when more trouble begun...
I'm wondering if they welded them up out of phase??
Can someone tell me if their truck's driveshaft is aligned or not??

if you had a new driveshaft made, then yeah, they could have it messed up and it prolly would cause you some problems.

from my understanding "phasing" is nothing more than MAKEING SURE THE YOKES ARE AT THE SAME POSITION AT BOTH ENDS OF THE SHAFT. i believe it does not matter how many shafts there are. you could have one shaft that is out of phase.


im pretty sure, they should be aligned..

OK , then you should phase them . It could well be your problem , and for what little time it takes to switch it, it will tell you one way or the other .
A link ,,http://www.remcotowing.com/PDF%20INSTRUCTION%20BOOKLETS/PDF%20INSTRUCTION%20BOOKLETS/DSC%20Instructions.cover.warranty2004vers.pdf

if you had a new driveshaft made, then yeah, they could have it messed up and it prolly would cause you some problems.

from my understanding "phasing" is nothing more than MAKEING SURE THE YOKES ARE AT THE SAME POSITION AT BOTH ENDS OF THE SHAFT. i believe it does not matter how many shafts there are. you could have one shaft that is out of phase.


im pretty sure, they should be aligned..

Yeah, I'm beginning to think they welded it up wrong. I've been reading the Spicer site and everything I see says the yokes should all be aligned, no matter what configuration you have.
The driveline shop did put a yellow mark on the shaft to make sure the front and rear went together properly but I don't think they made sure the ends were the same when they welded the tubes up...:mad:

OK , then you should phase them . It could well be your problem , and for what little time it takes to switch it, it will tell you one way or the other .
A link ,,http://www.remcotowing.com/PDF%20INSTRUCTION%20BOOKLETS/PDF%20INSTRUCTION%20BOOKLETS/DSC%20Instructions.cover.warranty2004vers.pdf

I don't think I can do this. Correct me if I'm wrong but if they welded the tubes out of phase and balanced them together then essentially they will have to be re-made, hence welded so everything is lined up properly...:confused::confused:

Do you see the weight welded on where it was balanced?

Do you see the weight welded on where it was balanced?

Yes, there are numerous washers welded on. They told me they weld them and then recheck the shaft to make sure there is no imbalance.