vibration on acceleration

[SS308]

ok guys need some insight. truck vibrates only when on the gas. if i let off the gas vibration stops. i first thought it was my tires but wouldnt it do it all the time? i only feel it when im slightly accelerating or maintaining speed. i cant tell where its coming from. the entire truck shakes. not bad, but definitely feel it. where do i look first?

Wait, you're always on the gas, so it would be a constant vibration...LOL!

 

[The Car Stereo Company]

ok, it is the u joint. now my next question is greasable or nongreasable? which one am i supposed to get?

 

[The Car Stereo Company]

im thinking nongreasable since the oem one has never been serviced. but want to confirm with the experts

 

[FordTechOne]

im thinking nongreasable since the oem one has never been serviced. but want to confirm with the experts

Non-greasable is fine; the grease fitting actually weakens the cross. That is why some of the newer designs have the fitting on one of the caps, which may or may not work in this application.

 

[The Car Stereo Company]

Non-greasable is fine; the grease fitting actually weakens the cross. That is why some of the newer designs have the fitting on one of the caps, which may or may not work in this application.

im looking and it seems i dont need any other parts other than the u joint? anything else you recommend replacing while im doing that?

 

[The Car Stereo Company]

i just noticed theres a u joint on the front too. are these the same?

 

[GCATX]

I don't know if they are the same, but definitely do both since the shaft is coming out.

 

[The Car Stereo Company]

I don't know if they are the same, but definitely do both since the shaft is coming out.

yeah, was planning on doing both now that i see there are 2 of them. hoping someone can confirm they are the same or different.

 

[Canuck714]

i just noticed theres a u joint on the front too. are these the same?

Yep same 1410 both ends of driveshaft.
Do the solid pin, non grease-able joints from Spicer. I had 100,000 on stock, got 10 on grease-able and just went back to the solid..
While you are there, check the slip yoke that comes out of T-Case.. Splines get sloppy, and its a special order part from Ford.

 

[Bulldog82]

If you were off-road, and a rock or stump struck the drive shaft while moving it could change balance of drive line. Not sure if there are weights on drive shaft, but a dislodged weight will result in vibration. My 2020 Screw has a label on the drive shaft stating if dropped, discard. Looks like a production line label left over and truck is too new to have weathered off. Good luck on finding the source. I have sold trucks in previous times due to vibration issues on a new truck. My thoughts are that it’s only going to get worse.