allison in limp mode

[skidsteer loader]

A buddy has an 03 D/A which is in limp mode, any fixes or does he have to go to the dealer

[Jim Cobler]

I would first check the fuel filter. I am not sure what you mean by limp mode but I have had my Duramax run but very poorly (Like 15 MPH). After I changed the filter, it was a tiger again. By the way, that was far short of the recommended 15,000 miles.

[skidsteer loader]

Thanks for the reply Jim, but I dont think its the fuel filter. He can only get the truck to about 3 MPH any higher and the tranny disengages and the gear indicator light flashes (the little line that tells you if you are in PRND) once the tranny disengages the truck has to be restarted but still cant be taken above 3MPH

[BassinRVer]

This does not sound like a limp mode but I could be wrong. My quess it is the NTSB(SP?) switch on the tranny going out. Have him cycle the keys couple of times. He will have to take it in if the NTSB is going out.

[skidsteer loader]

Thanks BasinRiver thats a definite possibility. Now my buddy tells me this started happening after the batteries went dead. (He has a seperate switch used to turn his amp on and off) says he left the amp on over the weekend, got in the truck, no juice. Jumped it with a booster and then came the problem. I have it trickle charging now to bring proper volts back to batteries. Anyone heard of this happening after a voltage loss?

[BassinRVer]

My truck was disconnected from the two batteries for three days and the truck was stuck in four wheel drive for 50 miles. So maybe if the batteries are disconnected electronic equipment act up. I strongly suggest cycling the ignition a several several times. Because after 50 miles and alot of cyles the truck came out of 4X4 and I still have errors on the three button controller and I have Service 4X4. When my ntsb switch went out and would not shift, I was told to cycle the engine several times and it would shift for the mean time, until it went completely out.

[skidsteer loader]

Thanks BassinRVer I'll give that a try. Are you still having the 4x4 errors, did you get the ntsb switch changed? My truck is brand new and I think I'd go nuts if I started having these BS problems

[BassinRVer]

The NSBU and the "Service 4x4" are two different issues. The NSBU switch is fixed. I am working witht the dealer to try and get the Service 4x4 issue covered under warranty. I have 37000 miles.

[skidsteer loader]

BassinRVer- Does your 4 wheel drive still function or is it inoperative? Ive tried cycling the key numerous times, problem still persists. How many times do you need to cycle the key?

[dmaxalliTech]

You need to get the codes pulled on that to find the definitive direction on this one.. I have installed these and forgot to hook up the turbine shaft speed sensor connector and it does the same thing.. check the codes and lets go from there
Eric

[BassinRVer]

I have the Predator and there is no code. I am driving around in 2 hi. The thing shifted out of 4X4 its own. I have no lights on three button control switch next to vent.

Eric,
Any comments on my truck? Maybe they did not hook something up. FYI, tranny upgrades last week.

[BassinRVer]

I cylced it once and it work like nothing was wrong.

[skidsteer loader]

Thanks for the info guys, He is just going to have it towed to the dealer cause Im at my wits end. I'll let you know the outcome. Still open for any advice.

DmaxAlliTech- Im considering a DSG powerbox after my truck breaks in a little, noticed you have a predator, do you reccommend one over the other? Any I should stay away from. I liked what Ive read about the DSG for keeping exhaust temp low and minimizing smoke and tranny slip.