Engine/Transmission (1998.5 - 2002) Auto transmission Problems

[CCiatteo]

I was driving in my friends 2001 2500 4x4 ExCab Longbed Auto and while on the PA turnpike, running empty at 70mpg the engine raced, the transmission temp idiot light flashed and so did O/D light on the column shifter. It acted like it "popped" out of O/D for a split second and did this two or three more times over the next few minutes. Never did it last for more than a split second. We immediately pulled over to check the fluid level and condition. Fluid had good color, no bad smell, but the level looked high.



I know an overfilled condition is not good, so could this becausing a foaming condition in the transmission which causes the problem described above? Around town the truck is fine. On the way home, same route, same load behaved perfectly.



The truck has around 80k on the clock and is stock to the best of my knowledge (my buddy bought it used about 8 months ago). It has the 3. 54 gear set, but came with big tires (305 or 315's on stock 16" wheels). Could the lack of gear combined with tall tire be causing the transmission to "hunt" when in overdrive. The problem is sporatic at best but has happend more than once so he says.



If an auto transmission is giving up the ghost which gear would be the first to go? First gear or O/D.



He does tow a 26 Enclosed Racecar Trailer a couple times a month so this issued needs to be addressed before something serious happens. When towing it seems fine, except for the tall tire which hurts acceration abit.



Any advice would be greatly appreciated.



Thanks

Chris

 

[CCiatteo]

Follow up and probable cause....

We think we found the problem. After lots of search in the board, we started to suspect the t-stat was weak because the temp gauge was wandering almost as if the t-stat was cycling excessively. So while we are there we start checking hoses and in looking for the petcock we notice the front of the radiator is plugged almost solid??? More searching led to the vent bottle design and the problemsn it causes. So we pulled the radiator (not a bad job at all) and pressure washed/degreased it and so far so good.



Do you think it is reasonable that the plugged radiator combined with summer heat, a/c running etc. could have cause the stock auto transmission cooler to become heat soaked, or just flat-out rendering it ineffective thus causing the transmission to run hot on long runs. Around town the transmission problems never showed, only on long runs?? Sound reasonable?



Attached is a pic of one section of the radiator prior to cleaning (wow).



Chris

I was driving in my friends 2001 2500 4x4 ExCab Longbed Auto and while on the PA turnpike, running empty at 70mpg the engine raced, the transmission temp idiot light flashed and so did O/D light on the column shifter. It acted like it "popped" out of O/D for a split second and did this two or three more times over the next few minutes. Never did it last for more than a split second. We immediately pulled over to check the fluid level and condition. Fluid had good color, no bad smell, but the level looked high.



I know an overfilled condition is not good, so could this becausing a foaming condition in the transmission which causes the problem described above? Around town the truck is fine. On the way home, same route, same load behaved perfectly.



The truck has around 80k on the clock and is stock to the best of my knowledge (my buddy bought it used about 8 months ago). It has the 3. 54 gear set, but came with big tires (305 or 315's on stock 16" wheels). Could the lack of gear combined with tall tire be causing the transmission to "hunt" when in overdrive. The problem is sporatic at best but has happend more than once so he says.



If an auto transmission is giving up the ghost which gear would be the first to go? First gear or O/D.



He does tow a 26 Enclosed Racecar Trailer a couple times a month so this issued needs to be addressed before something serious happens. When towing it seems fine, except for the tall tire which hurts acceration abit.



Any advice would be greatly appreciated.



Thanks

Chris