Driveline Vibration...Pinion Angle ?'s

[Kros383SS]

It seems ever since I installed the 4.56 yrs ago I've had a driveline vibration. With my old 383/700r4 and driveshaft it was always bad around 65-70mph.

Now I have the 6.0/4l80e and brand new shaft it still vibrates. It even has a new 1350series pinion yoke.

I havent ck'd the degree of angle yet but the trans is pointing down and the driveshaft is pointing down from the rear end to the trans

I'll have to look at the rearend but I believe it is pointed up.

Does anyone know how to adjust the pinion angle with a DJM 4/6 drop??

I do have a KentMoore Inclinometer and I have an angle finder so it should not be a problem.

[Wtfan18]

DUDE I have the same issue! and i have 4.56's it starts to vibrate at 70 and gets really nasty at 100... ive already shimmed the rear end to a -5 degrees. im going to have my driveshaft and tires balanced but after that i might just have to take it somewhere or something. im not really great with pinion angles and all that but let me know what you find. id rreally like to get mine to stop. i feel like something is going to blow apart when i go fast lol.

[Kros383SS]

I seems to go away around 75mph and I havent taken it past 85 yet.
I going to ck the angle first and make adjustments...try it and then swap front tires to back cause the back have no thread left on them.

Ya its getting really annoying.....

[Kros383SS]

Just went and ck'd the pinion angle.

I put my angle finder on the drivshaft and got 1degree maybe 1.5degree.

So I put it on the rearend and got .5degree down and so I put it on the trans pan and got 0 to .5 down.

So where should I go from here???????

Also ck air pressure in tires...it was 25psi and so I air'd them up to 35psi.

So whenever this damn rain stops I'll drive it again and take it past 100mph and c what we c.

[ff_jeff]

My Old 97 rcsb does that too. I think its a bad axle. Maybe a bent wheel. Maybe something else. When your driving, turn your mirrors down so you can see the rear tires. Look to see if the are wobbling. I think my 97 has 3.08 or 3.23 gears though.

[Kros383SS]

My Old 97 rcsb does that too. I think its a bad axle. Maybe a bent wheel. Maybe something else. When your driving, turn your mirrors down so you can see the rear tires. Look to see if the are wobbling. I think my 97 has 3.08 or 3.23 gears though.

Thats what I was thinking but awhile back I pulled the axles and ck'd them, replaced one of them cause the axle seal wore a groove in the axle itself.

Also rebalanced my tires and swapped fronts for back.

I just hope its not the ring and pinion.

Last time I adjusted the pinion angle I busted the tailhousing on my 700r4.

[nonecktribe]

Ummm last time i checked the driveline doesnt turn when its in neutral and you rev the engine......I mean come on you can install a HHO kit but not know this....

[Kros383SS]

And it only does this in drive? I mean, if you rev in neutral theres no vibration?

2nd, third, 4th gear....its speed related you have to be doing 55mph or higherfor it to start

I can shut the engine off and its still there...that tells me driveline problem

Ummm last time i checked the driveline doesnt turn when its in neutral and you rev the engine......I mean come on you can install a HHO kit but not know this....

thats Hi larious!!!!

[Kros383SS]

Well i shimmed the trans mount with two 1/8plates of steel. Bad idea cause the vib got really nasty at 60-65. The mirrors were vibrating as was the rearview mirror.
So I removed I shim and I was able to take it past 65 but the vib is still there but I guess the DS is spinning faster above 65 that the vib smooths out kinda.

I did take it to 85 and I was able to cruise there with no prob.

Anybody know if the ring and pinion or bearings would cause a vibration.???

And dont all reply at once......

[ff_jeff]

Ummm last time i checked the driveline doesnt turn when its in neutral and you rev the engine......I mean come on you can install a HHO kit but not know this....

Whats with this comment? That was a very productive statement. I mean you solved all of his problems. I was just making sure he doesn't have like say... a bad motor mount, trans mount, or maybe something else. If the engine vibrates when he revs it, he might have another problem... But hey, its not like your trying to help.