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2006 lly wont get past 70mph

3K views 4 replies 3 participants last post by  TheStepChild 
#1 ·
So just bought the truck, has 90k on it, and whilst driving it home the check engine light went on, the shifting became much more harder, and around 55mph until about 60, it sounds kind of like i am going over a rumble stip. I am going to get the codes checked in the morning, but was wondering if this is what the limped transmission sounds like? please let me know! Thank you in advance.
 
#2 ·
Have you checked your fluid level? Are your batteries and alternator good? These trucks do weird things with low voltage. But so this happened and you tried to go over 70? It could be in limp mode. Can you give us some more specs on the truck? What has been done to it? Has it been tuned?


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#3 ·
The only thing that I have seen is one of those Boxed superchips. I've had it all of 6 hours, so I have no idea what's been done to it, and got it from a dealership, and that is all they can tell me. It has a lift with 33's, lift looks about 4-6". Hard to tell. I haven't had a lot of time to dig through the undercarriage. As far as the 70, I got it to about 85 no problem, I was trying to get a feel for the acceleration, a while after that, I was going about 70, and the check engine light went on, then it had a rough shift immediately after, then I couldn't go above 70, and shifting seems rougher. The idle too seems fairly rough.
 
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