Hi everyone, im having over heating issues with my 06 lbz. Under normal driving the trans temp will climb above 200 and continue to rise until i pull over and let it cool. It started one day in about 15 degree weather the trans got to around 290 before i noticed it. I shut the truck off and let it cool to drive it 10 miles home. The next day after checking fluid levels, it was full. I then changed both filters and fluid because of the fluid smelling burnt. It seemed to be doing better until the following day when it got around the 250 mark. Once again i drove it home after letting it cool and dropped the trans lines and blew air through them to make sure they were not clogged. Trans lines have been replaced and i don't have and leaks. I'm not sure if im looking at converter issues or what but i noticed after the overheating the converter sometimes seems to stay engaged at a lower rpm than it should cause the truck to shove through the breaks if your not careful. I'm lost from this point. Any help would be great. Oh btw truck has 230,000 on it and trans is stock as far as i know. Thanks in advance.
Allison overheating
- Thread starter kmb06
- Start date
Does the torque converter lock at highway speeds? Or when in tow haul? (Should feel like a shift)
take the cooler line off going from the trans to the radiator and look in there and see if there is clutch material stuck in the fins inside the cooler make sure its the supply line to the cooler from the trans if so the convertor clutch is coming apart and plugging the oil flow through the cooler.
The easier way to tell if its converter is the color of the fluid and type of material in the pan. The fluid will be extremely dark, like black, if it is converter clutch material. Its very indefinitive to just try to look through a small port of a cooler for an undetermined amount of material.
The filters do their job very well. But if the fluid was very dark you say, maybe it had a sulfuric type odor, you're converter has had enough.
I have had them not have much in the pan and the cooler be plugged. if you can see clutch material in the cooler port if you have a good cell phone camera you can hold it down there and snap a photo and see it, it looks like wet cardboard material stuck in the cooler.
I see it all the time also in the cooler. When the converter clutch lining begins to break up it first goes directly in the heat exchanger. The big chunks can not pass through the honey comb. They need to be fished out through the cooler line opening.
You can flush it yourself but since you need to pull the transmission and at this point it will need to be torn down rebuilt and cleaned of all debris so don't bother at this point.
The instructions are here .
The instructions are here .
In the latest issue of diesel world they installed a bd cooler on a lb7. Said it dropped temps 60 deg. Looks like it fit well.
That cooler is not going to help when it's 15 degrees out and the trans is getting to 290 degrees....obviously there is a problem. In that kind of cold weather you'd be lucky to see 150 or 175 degrees. I'm sure the op wants to fix it not try and mask the problem. Besides I'd buy mikes cooler long before any of the others.
I wasn't posting as a solution but to inform the op and others of that option. Don't know if it really dropped temps by 60 deg, its just what they wrote in the magazine.