Just trying to figure out why my truck vibrates while acceleration, it never did this before and has done it for a couple months now, so we havnt been using it.

It vibrates at any speed while under acceleration, once u let off the accelerater it stops vibrating. you can somewhat cruise and it wont vibrate too bad but once u try to accelerate more it starts vibrating immediatly.

There is also a noticable humming noise in the drivetrain, only under accleration also, once u let off the gas, it stops.

When in park the driveshaft seems to have an easily moveable 1/4'' of play. but the U-joints dont seem to be loose, seems to be moving the whole part that comes out of the transmission? when you go from drive to reverse, or reverse to drive it makes a pretty loud clunk.

Also i pulled on the rear wheeles pretty hard in and out to see if there was any play which there didnt seem to be any.

any ideas of what all this could be?
figured id give as much info as possible, thanks guys.

 

Anybody?

 

i beleive the play is coming from the shaft that comes out of the transfer case, not the transmission? is this an expensive repair? someone wanna lead me in the right direction here

 

Im pretty sure there is a little play anyways, Dont quote me on that though.

Have you changed your transmission fluid lately? If so did you also get all the fluid out of the torque converter. The guy that did mine (I didnt feel like it in the middle of winter, outside) said sometimes they develop a shimmy, and there is some additive you can add to it to make it go away. I never had it happen so I didnt pry anymore into this additive.

Have you changed the fluid in your rear diff? May try that as well.

 

Have you considered a low grade misfire? Stumbling on accelleration?

 

wouldnt it vibrate when im in neutral or park and rev it if it was a miss fire?

 

sounds like a really good missfire....

.... or u-joints.... but idk its strange how he said it...


small chance but could his rear gears be messed up?

 

I've read it is the TC.... I have the same thing happening in my 2001 Screw with 150K miles.. My plan is to drain the TC on a fluid change, if no fix, then get the TC "refreshed."

 

correction, it actually does vibrate when reving the motor in park or neutral.......i was just out driving it and gave it a bunch of revs and everytime it vibrated the truck.....

 

Well i had a similar problem with my 8.8 axle recently. The rear axle carrier split all the way around near the center where its the thinest. When i would accelerate the broken ends would spin outward into the pinion gear and cause some violent vibs.

Only under accel though, once i would set the cruise at 50 60 70 mph it would smooth out.

Just something to check.

 

So your talking about the 97 right? Not your 06.

 

coil pack?...have you had a check engine light come on?

 

I'm seeing the same thing in my 05 XLT. It appears it only happens under load or acceleration. Weird vibration or shimmy and stops when you get to a steady speed. Ideas? Anyone know of a service bulletin on it? I've only got 65k on the truck, so isn't this a little early for transmission problems?

 

i just started getting a vibration when i go to make a turn from a stop. feels like the rear im guessing? hopefully its not something big on its way out