2007 Silverado 2500HD Transmission Slipping

Motogrrl · September 7

Just to point out - I am not a mechanic, but I am trying to educate myself before I take it somewhere to have it looked at as I am broke and if this is something I might be able to at least purchase aftermarket and get a friend with some know how to do I will. Any help is greatly appreciated.

I have a 2007 2500HD, VIN 1C6SRF JT2KN890086

Transmission slipping once hot. Not doing any kind of heavy driving. Checked and filled fluid properly, not overfilled. Had fluid flushed at a shop. Still slips. Not consistently however. No clear direction from the shop other than taking it to a transmission place which will likely cost me dearly I’m afraid.

Are there any specific known issues with these transmissions I might check? Are there any controls or computers or modules that tend to go bad that would cause this. Any other steps I could take that would allow me to troubleshoot further?

Thanks again,

motogrrl

CamGTP · September 7

The front pump is likely gone at this point. The pump is built into the bell housing and will get chewed up when the torque converter starts to fail. It sends metal through it and slowly kills it.

My opinion is that this point you are either looking a rebuild or finding a junkyard unit to swap it out with. If you go the used route, you will need to have it flashed at a dealer before you drive it, so it would need to be towed there as the TCM must be programmed to your truck. And if you go the used route, buy a new torque converter as well.

Motogrrl · September 7

Thank you - I appreciate the info. I had feared it was pretty serious due to age etc. Will see if I can find a decent used one to swap out and while the TCM doesn’t appear to be cheap it will still be cheaper than a whole new unit and labor. Thanks again!

2 hours ago, Motogrrl said:

1C6SRF JT2KN890086

CamGTP · September 7

You don't need to buy a new TCM, just a torque converter if you get a used transmission.

The TCM is part of the valve body on the transmission. If you find a low mileage unit, that would be best. Swap the transmission and converter out and then take it to be flashed so you can drive it.

Not really sure what low mileage used 6L90es are going for right now. You may also want to research which years you can use. There will be a year breakdown because the TCM might only be useable if say it came from 2007-2009 or something like that.