When ya got too much HP goingf to the wheels with a stock Allison as a fail safe one of two things will happen, stuck in third gear or Neutral.
It has happened so may times for me I do not even set a code, you can feel it starting to go and if you get out of the throttle fast enough you can avoid the SES - P0700 code from being set.
Man all this time I thought limp mode was when you got your six speed so hot the shift lever just layed over on the floor after a few minutes of hard use.
limp home mode is the term used to say when the vechicle
pcm see a problem it cuts back the fuel injection rate
on the duramax it cuts 4 of the 8 cylinders. 2 from each bank or what gm calls injector control circuits.
The tranny limp is like Tony described. The engine will limit rpm to 2000 when it senses a problem. It has full power up to 2000 but with an auto it is tough to get anywhere.
I did not know there was a tranny limp also. I know the getting stuck in 3rd gear happened to my friend and he had to shut off the engine and restart....cleared the limp and he was on his way again.
You don't have to go back to the dealer if this happens do you? Is there any other way to reset the SES light if this problem happens. This would be helpful to know
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