Auto trans issue

Hey guys, 08 double cab V6 w/auto trans, no leaks only 40k miles when at a stop it occasionally feels like the trans goes in and out of gear like you've manually moved the selector from neutral to drive. Anyone experience this?

 

try check trans mounts to see if any bolts loose. try grease drive shaft if applicable. could u possibly be feeling idle up from engine?

 

Are you running the A/C when you experience this by any chance?

 

x2

this is what first came to mind. A/C compressor kicking in.

 

It's a buddy of mine who owns this. I'll have to ask him those questions. I cant imagine this thing idling so low that the a/c surge would do that. He said it actually clunks like putting it in gear.

 

I have the same issue. Try searching axel wrap. I'm pretty sure this is what you are experiencing.

 

Axle wrap with the truck standing still?...explain?

 

Yeah, first time this happened to me was at a stop, in Drive and the A/C compressor kicked in. Slight "clunk". Like going into gear from Neutral to Drive.

 

Is a normal function of these trucks. The a/c makes it worse. It seems to me that it's the transmission shifting to 1st gear once you stop and/or the a/c compressor cycling. Both my Tacoma and 4Runner do this. Nothing to worry about, just make sure that when you stop at a light you have your foot pressed on the brake pedal good cause sometimes it jumps forward a little.

 

No it's bone stock. How the hell can the axle wrap when it's still under tension in drive???...makes no sense!

 

Don't sweat it. Our FJ has the auto trans. Sometimes we'll be at a light and the tranny will eventually decide (they must have a brain of their own... ) we're actually stopped and there will be a perceptible "bump" like you describe. I just think our trannys are not as smooth as some big American cars are.... after all, we're driving trucks, not cars!

I wouldn't worry.

 

Dont take it personally, I was a mechanic for 10+ years at a GM dealership. I understand what axle wrap is just didnt make sense on feeling a thud with your foot on the brake and not moving. One of those links mentioned the tranny "hunting" for a gear after it stopped...sounds more like that. Thanks for all the links, much appreciated.

 

yes I do but it's a 6 speed.

 

Totally agree with the a/c kicking in. Same thing happens on my truck. And remember, when you use the defrost option, the a/c is actually on.

 

Combine the normal trans shifting down to 1st gear after you stop with old and starting-to-wear U-joints in the driveline and you would get what your friend describes.