2002 Overdrive Problem

My girl's dad has a 2002 V6 Access Cab 4x4 with 241,000 miles on it. He knows his vehicles, but he's run into an issue lately and asked that I post here for suggestions.

His truck struggles with overdrive during certain conditions - towing, with a load in the bed, and now going up hills. He describes the problem as the truck slipping in and out of gear, kind of "bouncing" the truck a bit. He said the problem first happened a while back, but it was a single bounce, to where he looked to see if he hit something. Now it's gotten much worse, and he's unsure what could be causing it. He's unsure if it's in the transmission (it's an automatic) or elsewhere.

He has no problem taking the transmission apart, if that's what the problem is. He just asked if I could make a post to see what the suggestions were. He would hate to drop the tranny to find out that wasn't the issue.

Anyway, if I get more information I'll post it. Thank you all in advance.

 

Bump.

Any ideas?

 

sounds like you may have a bad band in the trans

 

Its possible that it could be that the torque converter clutch is failing or the direct clutch is going. What you could do is go on ttora.com and download the toyota fsm that contains the diag and mechanical info of the a340f transmission. You should check the trans fluid,if the fluid smells burnt its toast. The fluid should be red in color. Now if the fluid is red in color and smells burnt its toast. In the toyota fsm it dosnt tell how to rebuild the a340 series trans. Toyota dose sell fsm books that show exploded views,but you would have to go to the dealer and see if they can get you one. But theyll just try to sell you a rebuilt one from toyota. Keep use updated on what you find.

 

I found out tonight that, amazingly enough, it was a bad spark plug. He took it to a transmission guy who immediately recognized the problem. He could replicate the "shake" by simply pushing in the brake and hitting the gas, while in gear. A new set of plugs and coils, and bam, problem solved.

It blew my mind like it did my girl's dad, but it was a hell of a lot cheaper fix than rebuilding the transmission!