I have a 2005 GMC Envoy with four wheel drive. When at a stoplight, with my foot on the brakes, occasionally it will feel like I have been hit from behind. A sharp clunk but since I am on the brakes the car does not move forward but I feel that if I were not on the brakes it would move forward. One dealer shop suggested that it was a problem with the “yoke slip joint” in the drive shaft. Another dealer shop thought it might be something else. Has anyone had the same issue and could describe your solution.
I’ve noticed something similar on my 4WD Ford truck. On it anyway, it is causes by the limited slip rear differential, and is normal. If your Envoy has a limited slip differential (sometimes called a “locker”) and this clunk is really noticeable, I’d suspect the differential clutches need to be replaced. I had to replace the differential clutched on my Ford truck one time for this. In my case the symptom manifested itself especially when shifting into reverse, like when parallel parking. But it happened just when in Drive, coming to a stoplight too. Just not as much. Replacing the clutches helped quite a bit.
The yoke slip joint could cause this too. But it should be possible for a mechanic to test that idea by crawling under the car and twisting the driveshaft here and there, see if there is any play.
Edit: One other idea, if the differential fluid was replaced or even just topped off, it is sometimes necessary – it would be called out in the owner’s manual usually – to add an additive to prevent this symptom.
I had that happen with a GM vehicle I owned.
It feels like someone hit you in the rear and you look in the rear view mirror and nobody’s there.
A week later the transmission gave out.
The problem might be with the sun gear reaction shell.
There is a TSB about that “feeling of being bumped” problem and it involves removing the drive shaft and greasing the yoke. Go to GMTNation.com. There are many threads about it.
GM has a TSB about this. It involves removing the drive shaft and greasing the yoke slip joint. Go to GMTNation.com. Just type in “Feeling of being bumped”. They have a thread about it and just about anything else you’ll need to know about the Envoy.
GM has a TSB about this. GMTNation.com has a discussion about this. Just type in “Feeling of being bumped”. It involves removing the drive shaft and greasing the yoke slip joint.