ok tonight i was setting at a red light.
no one around me.
then out of nowhere it felt like my truck got hit.
i jumped from the truck and ran to the back to find nothing there.
this is the second time this has happened to me and my husband said it did it to him 3 or 4 times.
who here has had this happen to them?
what is it?
should i take it in or is this normal?
any one who knows what this is and what i should do.
please help me out.
thanks all

 

Hmmm. Never happened to my 2010, own it since february.
Although sometimes my transmission shifts from 1st to 2nd gear with a little sort of bump. Mostly when Im rolling slowly during the red light and than take off on green.

 

I used to have a Chevrolet Caprice police car that would suddenly make a jerk or bump while sitting still, sometimes 10 minutes after stopping. I've had drivers sitting in it jumand open the door to get out thinking it was hit. We went over that thing with a fine tooth comb several times, never found the source.

It was a 1986 with 350 4bbl and 700R4. I think it was a delayed release of a clutch or band in the transmission. It'ld be in park, sometimes I had already gotten OL and reg and was writing a ticket when it done it.

I traded it for a new car at 120K and it was still doing it?

 

How long were you at the light before this happened? Is it possible you had let some pressure off the brake pedal just enough to let the truck inch forward a tiny bit? Did you perhaps make a fairly brisk stop when you came to the red light?

It sounds a lot like a sticky drive shaft slip yoke. This is where one piece of the drive shaft goes up inside the other and it is designed to telescope a small bit to allow for changes in length caused by movement of the rear suspension. There is supposed to be grease up in there to allow for smooth movement in and out.

When you come to a stop, particularly if you are stopping quickly, the back of the truck tends to kick up in the air which would cause the slip yoke to move out, lengthening the drive shaft. Normally, once you stop the rear suspension settles back down to its normal ride height, but that can be inhibited by a sticky slip yoke which keeps the rear suspension up high.

Typically, if you let off the brake, it will help "unload" the rear suspension and it settles back down. With that sticky slip yoke, you will usually feel some sort of bump. The stickier it is, the bigger the bump or lurch. Sometimes you don't have to let off the brake to unload the suspension and overcome the friction of the sticky slip yoke because the weight of the truck itself will eventually overcome that friction and you'll feel the bump.

These trucks have had issues with not having enough grease in the slip yoke from the factory which can cause symptoms similar to what you describe. It certainly could be something else, maybe in the transmission.

 

Your truck wants to be moving. She wants you in the throttle and is having a hard time holding back all that power. hahaha

 

That's what a warranty is for - I'd certainly take it in and at least get your complaint documented if nothing else.

 

It's your trans shifting gears, try slowing down longer you will notice the bump goes away, then slow down fast and the bump comes back. This is normal if you ask the dealer.

 

I second the suggestion of a sticking slip joint

 

thanks all i have made a date with the dealer this morning. only thing is Sean is on the job. so i have to take it in buy my self and we all know how a dealer treats a blond girl with big *****. ( like iam a air head ) all thay look at is my 36 D's and vary rarely look me in the eyes

 

That can actually be to your advantage..........

 

i too have this problem on and off. It hasnt happened in a while. It happened alot right after i got the truck. The first time, I too thought somene hit me, i was pissed untill i noticed no one was behind me HA

 

Again .... Welcome Becka!

Men are like "visually" oriented animals, it's in our DNA, it goes back to the hunter days. Women read the menue at IHOP, men look at the opics and ask the women "what's good" and then when the waitress arrives, orders by pointing at a picture while staring.

Just sayin' ya know.

Take care ....

 

This used to happen to my truck but I've had the transmission re-programmed and the driveline slack removed. Not sure which one fixed the issue but one of those must have done it.

 

hey i took my truck in this morning. guess what thay fixed it! it was a technical service board all about it. it seems to be fine now! YA ME lol thanks for the help dinner is on me lol.

tbear853 and glc, at my age i have found if i use my body to get what i want its hard to walk normal for the poor boys. lol sorry thats a little off color but true.

 

Did they say what it was exactly?