Transmission problem?

[Wagnasty]

To start off the vehicle is a 2003 Yukon Denali XL with 230k miles. So back in the spring I began to have transmission trouble. Originally it started as a chatter or shudder around 40mph during normal driving/accelerating. It did it for a few months and then the transmission started slipping. Pulled the pan and there was a lot of aluminum and friction material. Did a fluid flush and made it a little better but I still ended up pulling the transmission.
Fast forward a few months and I was able to find a used in good working order transmission with 80k miles. I get the transmission put in and it still has the exact same chatter/shudder problem. Other than that it drives fine. I dont get the problem if I drive with tow haul activated or if the vehicle isnt up to normal operating temperature.

Is it possible I got another transmission with the exact same problem (drove fine in the other vehicle) or could it be my ecu?

 

[SLCHOE]

http://transmissionrepairguy.com/torque-converter-problems/

 

[southboundchicken]

Did you change the torque converter?

 

[ccapehartusarmyINF.(ret)]

Did you change the torque converter?

same question

 

[Wagnasty]

Sorry I left that out. But yes I changed the converter out.

 

[ccapehartusarmyINF.(ret)]

ll yes it is possible you got another tranny with the same problem but highly unlikely
Torque converter shudder in 4th while lockup is engaged; problem goes away when the brake pedal is pressed slightly to unlock converter: Need to verify line pressure, and provided no valves in the TCC (Torque Converter Clutch) hydraulic circuit are worn, replace the torque converter.
this is the closest i could find the the 30 most common 4l60e problems but it doesnt sound like thatll be much help

 

[Wagnasty]

I got to drive the other vehicle prior to getting the transmission out of it and it was fine. I did have someone help me swap the transmission out of my denali. So I guess there is a possibility that the ood converter could have gotten used because the replacement I got wasnt marked. My luck would be that the old one got reused.

When I drive today I will leave tow haul off and see if the problem stops when I hit the brakes. Assuming I do this while accelerating?

 

[OR VietVet]

I would lean toward the convertor as others have said but also maybe the signal and pressure like capehart said.

 

[Wagnasty]

I read that link about converters and symtom wise its exactly what ive got going on.

So I just took the truck out and got it up to temperature, turned tow haul off and at 40mph it started chattering/shudder. Feels like your driving on an extremely rough road. But I touched the brake pedal and it immediately stopped. Removed my foot from the brake and went right back to doing in.

My luck is its probably the converter.

 

[ezdaar]

http://www.oreillyauto.com/site/c/d...ck=Search_N0444_1022397_-1&pt=N0444&ppt=C0207