2002 1500 silverado tranny problem

My 02' silverado 1500 HD has a 6.0 liter engine. When the truck is first startex and driving on the highway the overdrive slips in and out of gear. after about 15-20 mins it pretty much stops. i have the fluids up. anyone have an idea or experience such a thing? how costly is it?thanks

My 02' silverado 1500 HD has a 6.0 liter engine. When the truck is first startex and driving on the highway the overdrive slips in and out of gear. after about 15-20 mins it pretty much stops. i have the fluids up. anyone have an idea or experience such a thing? how costly is it?thanks

having the drive train codes will narrow down the problem. GM specific code scanner will be required to gather these codes.

usually this would be worn valve bodies/losing pressure. could be a low cost fix , however if these are worn it says the transmission is in need of rebuilding since the fluid most likely was not changed/overheated and the dexron III turned into an acid fluid erroding the fluid passageways.

use only the new approved dexronVI in this transmission as this is the proper fluid not dexron III. this was changed in 2006 by GM...

So i take it there is no possible chance i could trouble shoot or fix it myself?

So i take it there is no possible chance i could trouble shoot or fix it myself?

well it is unknown what your abilities and equipment available are. with no $2,ooo scanner and tools to drop and clean /inspect / pressure test / repair manuals etc this would be much more than a tune up and what most members would consider doing.

even if you got all this and did this for the first time with no teacher you will screw something up. could end up costing much more . loss of vehicle use also.

you may not need a complete rebuild. get the drive train codes and post them so we here can give you some idea of how bad it is.

dropping the pan will also reveal the condition with the type of pan debris/fluid color/smell etc...

you ever change and replace tranny fluid /filter ?

what tranny is it?? It should be written on it,

It can be as simple as a wire or a bad valve body as j cat said,

You should have a DTC or check engine light on.

what tranny is it?? It should be written on it,

It can be as simple as a wire or a bad valve body as j cat said,

You should have a DTC or check engine light on.

THE 1500 has the 4l60 the 2500 has the 4l80. still the dtc drive train codes will be the same. same type components and most all the wiring.

I will see if autozone can pull some codes off of it.then ill post it. this morning on the way to work it kicked out once(going 73mph) on the hiway. it was about 69° outside. wonder if that makes a diff.

I will see if autozone can pull some codes off of it.then ill post it. this morning on the way to work it kicked out once(going 73mph) on the hiway. it was about 69° outside. wonder if that makes a diff.

since you did not answer my questions , I do not recommend that you do any work on the transmission.

also go to a transmission service shop to get the codes retrived. auto zone I believe can only retrieve engine codes..

I guess you do not understand what GM specific drive train codes mean when reteival of these are required.