Bumping sensation

[Dispointed]

Just had 2014 ltz trans complete rebuild.recently had a bump while at complete stop engine idling.Similar to being bumped at rear by another vehicle.After have experienced periodically.Transmission rechecked shows no codes ,only O2 sensor code . Any insight as 3 qualified mechanics can not I D 103 k mi

 

[mikez71]

@NickTransmissions ?

 

[NickTransmissions]

Just had 2014 ltz trans complete rebuild.recently had a bump while at complete stop engine idling.Similar to being bumped at rear by another vehicle.After have experienced periodically.Transmission rechecked shows no codes ,only O2 sensor code . Any insight as 3 qualified mechanics can not I D 103 k mi

Normal. My 6L80 in my 2009 Sierra does the same thing on occasion...It occurs when I tap the throttle then immediately let off and brake when coming to a stop. If it begins to happen more frequently or other symptoms begin to present, contact your builder or company that performed the rebuild work for recommended next steps, including potential warranty claim.

 

[Dispointed]

Thanks

 

[Gearz]

The splines in the slip yoke may be worn out. You would have to change the yoke at the transmission or transfer case 4x4 and a new u-joint. This would happen on the older GMT800 trucks so they came out with a nickel plated splines. I would also change the T-Case fluid at the same time.

 

[Chughart]

i get the same thump and i have changed the front diff mounts, trans mount, engine mounts, rear u-joints, "greased" the splines on the drive shaft, have changed all the fluids, and i still get the thump. my next random repairs will be rebuild front diff, rear diff and transfer case but kind of 2 birds with one stone, regearing diffs and figured id freshen everything up while im there.

if you find a solution i would love to hear it cause the thump drives me nuts.