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Transmission Issues

2K views 8 replies 4 participants last post by  qcfijon 
#1 ·
New here and to diesels. I have an 08 180,000 miles, only upgrades are k&n cold air and magnaflow exhaust with deleted filters. The exhaust was done before I bought it. Driving home yesterday pulling my 16ft enclosed trailer as I do everyday I got a loud thud, the tranny shifted down to 5th, abs light, check engine light and brake light all came on, then the speedo started going crazy. When i got off the highway it did not want to move, rpms were hitting 2000 just to get going, when i got to 30mph it seemed to start going fine. . Tried to manually shift and it would not let me and tow haul was stuck on. Got to my shop knowing i needed new batteries, put new batteries in, all lights went away except check engine, it drove home fine. Got in it this morning and it does not want to move, i could manually shift but it did not help. It is very cold here yesterday and today, not sure if that is the issue, saw some posts about shift solenoids sticking but doesnt seem like that is it. Maybe a converter not locking? Hoping you guys could shoot me in the right direction. Thanks
 
#3 ·
When the CEL comes on, the trans is in "Limp" mode-- max 2k RPM, and 3rd gear. It will also set fault codes, and that will help diagnose the problem. [Restarting the engine seversal times will take it out of "Limp", but the codes will still be stored.

You need to pull the codes- [cheap readers do not read trans codes] Some part stores will do it-!
 
#5 ·
#6 ·
Almost exactly what happened to me. Mine did not say anything on the message screen either just check engine light but also abs light brake light came on. Tried to check trans temp and it wouldnt read either. I had been having issues with it starting in the cold so i knew it needed batteries and was thinking it just wasnt getting enough voltage. Replaced the batteries drove fine until the next morning. Went to oreilly and had the codes read printed off then cleared. 6 different codes but all were clutch slippages or computer malfunction, so thinking it was just a lack of voltage that made everything go haywire. Went ahead and drained the tranny anyway and replaced external filter. Fluid was a little dark but not burnt, little metal on magnet around the filter threads but expected with 183,000 miles. Got about 20 miles on it since, no issues, shifts great under soft or hard acceleration, no lights have come back. Have not put the trailer back behind it yet but hoping all is good now.
 
#8 ·
This is all good stuff to know. I just bought my LMM DRW to help to my 13k boat easier. I don't usually push the truck, I'm a big fan of momentum. Sounds like it's also nice to have that autocal to scan codes right when something acts up.

Thanks for sharing guys:thumb
 
#9 ·
Well same thing happened again this morning. Same lights came on same hard downshift. Turned it off and got it out of limp mode, but obviously not the fix I was hoping for. Any ideas? Thinking maybe wiring, the trans temp was 136, so it is not ovsr heating the trans, engine temp 210, but cold outside again. Could the fuel be starting to gel and causing this, 8 degrees outside right now.
 
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