I own a 2004 2500 silverado LT LLY duramax with 1700 miles on it, I was towing a boat that weighed Aprox. 4000 lbs and my truck wouldn't go over 65MPH, if I tried to take it over 65 it would start cuting out and loosing power http://www.dieselplace.com/forum/smileys/Angry.gif. When I pulled off to the side of the road and pushed on the excelorator it would not go over 2000 RPMs, it would start cutting out on me but would not go over 2000 RPMs. After I got to my destination I unhooked the trailer and pulled it forward and it was still doing the same thing. After shutting it down and waiting a few minitues I started it up and it was fine, any thoughts?http://www.dieselplace.com/forum/smileys/Disapprove.gif By the way, I traded my 99 Powerstroke in on this new truck because of the HP and Trq the Duramax has.


Thanks Russ

Sounds like "Limp Mode" on the Allison... Someone with far more knowledge than I will chime in soon, though.

My '02 will not rev over about 2000 rpm's when in park. My thought is that it is a rev limiter. In neutral, it will rev higher however.


I can't answer the 65 mph situation. I've never had anything like that occur.








Kevinhttp://www.dieselplace.com/forum/smileys/Big Smile.gif

I just towed my neighbor's 25' Searay that weighs over 7,000 pounds last weekend as a test of my truck. 75 MPH on the freeway and didn't know it was even there. Up a 14% grade at 52 MPH, 3000 RPM, 1150 EGT, Trans and engine temps spot on. 70 degrees. No power add-ons. In Tow-Haul mode.

Fuel filters always suspect.

Russ, did you have all the gear indicator lights on the DIC or did it ever show an SES code?


Doug

Doug,
Yes I had all the gear indicator lights and the SES never came on.
I took it to the dealer on Thursday and they ran it on the scanner and it had the code P103, they told me it has to have all 8 of the injectors replaced which will be done on Tuesday. They said there were no error codes on the tranny. Hope it takes care of it.
Thanks Russ

I have basically the same truck, a few less miles. The identical thing happened to me a couple of weeks ago. Two buddies and I were headed to the mtns with our dirt bikes. We had about 45 miles of freeway, then about 5 on a secondary hwy. I stopped for a stretch at the btm of a long grade.


When we started up the grade I thought I'd show my friends how much power was available. It accelerated just fine then about 1/2 way up the grade it started slowing down. Wouldn't go above 2k rpm. Downshift and it ran even worse.


We were only about 7 miles from a dealer so I went there. He pulled the code, don't remember the #. He then went through the diagnostic routine the computer told him to. After about an hour of dicking with it, he came to the conclusion from the tests that it was the ECM. Of course they didn't have one in stock.


He put it all back together, it ran fine and has ever since. The only thing he really did was to unplug/plug in several connectors. Conclusion: loose connection somewhere.





David