Transmission feels like jerking forward

my truck is doing this weird thing that when i'm at a dead stop with the gear on D and my foot on the brakes my truck sometimes feels like the tranny wants to jerk the truck forward. not sure if anyopne out has had the same thing happen to them. any thoughts as to what causes this. my truck has around 93k miles.

 

I had a similar feeling the first few days of driving my truck , I had started to let up on the brakes and would feel this. Instead I just keep a constant pressure on the brakes..

 

I don't think it the a/c because I don't run it. maybe you're right about it not downshifting to first.

 

If you are using the defrost setting the compressor is on whether you want it to be or not.

 

I get the same thing in my 06 pre runner. I thought it had something to do with the ABS. First time Ive ever had ABS so I didnt give it much thought. It only happens once in a while not every time I stop.

 

Just last week, this started happening to me, too, but not all the time. I'll be at a red light with foot on brake, engine revving at ~600rpms, then it jumps to ~850 after about 10 secs from initial stop. I can feel the car jolt a bit then revs down to ~600 again. (Today, this hasn't happened, though.)

 

6000 rpms? seriously? isnt that kinda high? sorry if this is a stupid question, just wanted to know

 

Sorry, 600rpm

 

ahh ok

 

I wish my rev limiter cut that high. Mine cuts at 5250ish... Hard to impress the ladies when your limiter cuts in the middle of a burn...

 

It is very common. You can search on all the Taco sites for "Surge" and come up with a ton of threads.
Could be either shifting to first or torque converter unlocking. Some cured it by having the dealer check the tranny fluid level which may be low.

Fritz

 

Has anyone mentioned possible 'axle wrap'?

 

Unfortunately we all hate that surge/bump. I wonder if the 09' guys feel it too?

 

Yeah, my truck does it also.
In fact.... ever since I got the flowmaster exhaust, you can HEAR the truck when it throttles up. It does some weird stuff sometimes for not apparent reason. I've mentioned this before, but I've sat in drive-thrus waiting for food, tranny in D (auto), foot on brake.... truck is idling. It'll surge weird... UP in rpm's for a minute or so, then DOWN in rpm's for a minute or so. The swing is probably only 200rpms - but enough that I can hear it.
If I let off the brake just for a second (or less), the thing JUMPS up in rpm's (more so than the surging). It'll do this with nothing running (no heat, no fans, no a/c, etc). It'll also increase in rpms if I turn the fans on low.

 

How can u have axle wrap stopped at idle?? Axle wrap only occurs during hard acceleration

 

That was my next question.

Mine occurs after I have come to a complete stop at a light. 10 to 30 seconds after I have stopped. Sitting there minding my own business and then bump. It almost feels like I took my foot slightly off the brake but it has happened enough time that I purposefully keep quite a bit of pressure on the pedal.

 

I guess if ur worried, put the parking break on when u stop, its not too much work, i use my parking break everytime i stop so i dont need to worry about the break pedal.