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Discussion Starter · #1 ·
Hey there! First time posting but really need some help. 3 days ago I changed my tranny fluid, did lots of small driving and stuff around town, yesterday had to leave town for work and got 30min outside my home town and truck shifted hard into 4th no other gears. Well, obviously limp mode but I still wouldn’t know why, next day same thing. Now the codes are clear and it isn’t horrible. But I just want to know where to start, when I get home I’ll mess around with the TCM wires like a lot of people have suggested to me but since the tranny fluid change was so recent I’m very confused. Curious if you guys have any other random ideas then just building a tranny, I hear it can be the TC, I did just put it into 4x4 about 3min before it happened? No clue at all would love some help, also got the P0700 and a glow plug code but I don’t think that has anything to do with the tranny issue? Thanks for any support really confused what my next step is.
 

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when I get to the shop in the morning I’ll check my book and tell you what the book says. That is a incorrect gear ratio code, it sounds like it slipped out of 5th back into 4th causing the limp. Did the old oil smell burnt, looked burnt, and metal? And did you drop the pan to change the internal filter?
 

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Discussion Starter · #6 ·
when I get to the shop in the morning I’ll check my book and tell you what the book says. That is a incorrect gear ratio code, it sounds like it slipped out of 5th back into 4th causing the limp. Did the old oil smell burnt, looked burnt, and metal? And did you drop the pan to change the internal filter?
Dropped the pan and changed that one too, I appreciate it, the levels are fine, haven’t been this confused in a while, just hate that it’s happening so much now, thanks.
 

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Discussion Starter · #7 ·
when I get to the shop in the morning I’ll check my book and tell you what the book says. That is a incorrect gear ratio code, it sounds like it slipped out of 5th back into 4th causing the limp. Did the old oil smell burnt, looked burnt, and metal? And did you drop the pan to change the internal filter?
Dropped the pan and changed that one too, I appreciate it, the levels are fine, haven’t been this confused in a while, just hate that it’s happening so much now, thanks.
Oil did not smell burned at all but when it was in limp shifted very hard.
 

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Pull the plug to see how much metal comes out. One of the speed sensors screws into the TX case. If something is screwed up in there, the ECM could read that as a 5th gear issue, even if the tranny is 100% perfect.
 

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Discussion Starter · #14 ·
Pull the plug to see how much metal comes out. One of the speed sensors screws into the TX case. If something is screwed up in there, the ECM could read that as a 5th gear issue, even if the tranny is 100% perfect.
Could be a TX case issue.... jumping in and out engagement . You did say it's a 4X4 .
Okay sounds good thank you
 

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C3 clutch pack may be smoked. Do you have a tuner? If so, turn it down and take it easy on the trans. Rebuilding may be your fix.
 
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