Transmission Overheating -help!

[Paddy McMahon]

48 RE transmission with 4k on a Goerend torque converter and valve body with a Mag Hytech double deep pan. Two days ago while returning home the transmission felt like it was lugging then the trans temp idiot light and tow/haul light started coming on at about five second intervals. I have a Pac-Brake exhaust brake that I use routinely. This all occurred after cruising over a mountain pass at 55mph and coasting down the back side with the exhaust brake engaging intermittently. I babied the truck back to town, turned it off for 30 mins and let it cool off. Checked the trans fluid-normal level and loooks brand new, not smelly or burnt. I do not have a trans temp guage. fired up the truck and drove home-idiot lights and chime still flashing on/off at intermittent times. I am planning on driving the 50 miles to the shop where I have my service work done. Do you think this is a bad idea? Any thoughts on what is going on? I have tried turning off the exh. brake and the tow/haul without any luck resolving this. I truly drive this truck like an old man so i am surprised by all this. (Checked for trouble codes with SMARTY and none shown. )

 

[Paddy McMahon]

I made the run to the mech shop and it was uneventfull. Using the brake and the tow/haul during the last couple of miles before I arrived I could not replicate the situation to get the idiot lights to come on. Hopefully this is just an electrical glitch that will be easily resolved.

 

[Yo Hoot]

Keep us posted. I have had some heat issues myself with my Goerend.

 

[Paddy McMahon]

Truck is back on the road and no one can find anything wrong with it. No codes were even thrown for transmission temp. My mechanic suggested that this may simply be an electrical issue as the truck is presently running fine and all the transmission components checked out OK.

 

[p-Bar]

My first thing I would do if I owned that truck is put a trans temp gauge on it. You have a lot of money invested in the truck.

 

[rbeyer]

Check the Edge

I had an odd event when driving highway 5 from Disneyland to Alamo, CA. My headlights came on after the truck was closed and locked. We were in a Subway in the Santa Clarita Valley and I saw the lights when I sat down to eat lunch -- a very odd feeling. The problem repeated each time I stopped, so I had to disconnect the batteries to create a shut off. Anyway, this occurred during the day and I was not using the lights. It was very odd.

The folks that service my truck, Left Coast Diesel in Dublin, CA removed the Edge/Attitude and the problem disappeared. Might this be the cause of your problem?

 

[Yo Hoot]

The only way I got my Goerend trans to stop heating up was to drill out the drainback valve and add an aux cooler. Depending on the stall speed of your TC, heat will build up when she's not locked. I still get a heat-induced premature upshifting episode once in a while. Granted the temps aren't going through the roof. I have a temp gauge on the way but it looks like at around 237F fluid as read with a scanner puts my truck into this strange upshift mode. According to the service manual it should not do anything different until 260F. I either have a goofy ECM or Dodge changed some coding along the way without explaining it in the service manual.

 

[Paddy McMahon]

well truck started acting up again. I took it in and had the codes checked while the problem was happening-looks like the trans temp sending unit has issues as my temps were going back and forth from 130 to 260 degrees and everything in between. Nothing wrong with the trans, TC, etc. Aside from replacing the part I am going to install a trans temp guage so I don't ever have to worry about cooking my transmission again. Than you for all the replies gentlemen.

 

[Yo Hoot]

I replaced the temp sensor, the valve body and the shift switch. Nothing worked except getting the thing to run cooler by drilling out the drainback valve and adding an aux cooler.

I have read a few places that the 48RE and the computer/electronics can be finicky when going to built transmissions. Mine does not like temps over 230 deg and you will get that once in a while with a lower stall TC.

I'm trying to get a temp gauge but Diesel Manor put me on backorder... was supposed to be shipped early August but still no word.

 

[Paddy McMahon]

Been back on the road for a week now w/ out event. Goerend customer service for a replacement sending unit was terrific and my mech had it replaced in no time. Truck runs great.

 

[WKruger]

Good deal!!