o9 KW vibration, shakes under acceleration

U-joint?...

 

Possibly your leaf spring bushings as well. If it does it when your taking off as well. I started in low the other day and the truck kinda shook and hopped went into the shop bushings were completely gone on the passenger side half gone on the drivers. Called peterbilt 30 kits in stock asked if it was a common problem guy says oh yea we see a lot of these. Called kw to see if i could get the same part at a better price and save a few miles to pick them up guy says we sell a lot of these for both peterbilts and kws. Could be that as well might wanna check those on both front and rear drive axles. But as the other poster said could be ujoints as well. Easy check for the bushings dump your air listen for creaking and clunking as well.

 

I had the same problem in my Ford F250. Turned out to be the rear differential. Rebuilt it and viola, no more vibration.

 

U-joints would be my guess also. Could also be a pinion seal in the pumpkin (diff) If there isn't any fluid leaking then it wouldn't be the pinion seal.

 

Carrier bearing would be my guess.

 

I had that issue some moons ago, it was u-joint between axles,
if that is good, well my friend in his pete had an annoying shake
and finally had the drive shaft remove and rebalance that fix the issue
good luck.

 

I ment to say drive shaft

 

With an 09 you will be able to have the shop hook the computer up and do an injector performance test.