Well for the past little while I have been having some strange things happen with my trans. When I start up my truck and run it around it won't lock up the converter in any of the gears for about 5ish minutes and then it will lock up in OD provided I am going fast enough for that. After it runs for a while longer it will start to lock up in the lower gears too like it is supposed to. Do any of you know any reasons why it could be doing this? Oh and I'm not sure if this is related but when I put on the brakes and slow right down to like 20kmph and below there is a wierd grumbling sound that happens. The brakes don't feel off or anything and look like they are in good shape. Could this be because the tranny is doing funny things or is it totally unrelated... Thanks for the help!

Josh

 

the trans sounds normal, the converter clutch wont engage until a set trans fluid temp.

the brakes sound could be rust on the drums or nasty rotors

 

trans is normal like Joe said. Its in the programming to help the trans warm up. The TC while unlocked create more heat so they leave it unlock to heat the trans faster. I don't really like the system. I am hoping TW can remove it via a chip!

 

Could be as c00n and Tj state.
It could be in cold shift schedule.

My question is has it allway's done this?
It has warmed up a bit (amb temp). You could have and out of range
TFT sensor.

Try this.
When you drive away after the cold start. Let the trans go thru the gears.
Then come to a full stop. I mean a full stop! Then drive away. See if it will change the shift schedule.

Bill