abs/brake light coming on under a lug
 

when i lug it or get down on it my truck flips abs/brake light comes on and might stay on about 5 miles then goes out no codes no nothing but if u shift normal and drive normal its fine not a big deal but drives me crazy having a light on on the dash

same thing with mine not sure what causes it exactly but i know what you mean

my 06 5.9 did the same thing, never could figure out why.

if you look at one common thing with the trucks that have done it on this thread it is they are both manuals and they both have dual disk clutchs in them, for some reason there are alot of trucks this happens to when they are lugging them below 1500 rpms, and noone has been able to figure it out yet. Last I heard there was a guy that was going to hook up a starscan, or tool to read the abs info and try to log what happens when it trips these lights to see why it is doing it, but i dont think he ever got around to doing it, but pretty much any 6.7 with a dual disk clutch that lugs it will trip the lights.

I don't think it has anything to do with the dual disk. From my understanding its because the braking system is ran off the power steering pump along with steering. When you lug the engine, you loose hydraulic pressure going to the brakes because the engine isn't turning over as fast. I had the inner lining of my power steering to hydro booster hose come loose and lodge into my break setup causing fluid restriction to my brakes..the lights came on until RPM's were high enough for adequate flow, I pulled the liner out and haven't had an issue sense. When the liner comes loose you will hear a hissing noise coming through the fire wall. its a common problem.

My automatic did this once when the wife was driving. I was in the truck, it came on when she tried to turn the wheel without the truck rolling and gave it very little throttle as she started moving. (She was manuvering into a parking space). We went in and ate, I had the next driving shift and the light never came on when i started it, no codes. I figured it was either a low voltage or one wheel binding and one rolling when she did the turn.

I have the same problem and I agree w KMKDiesel, I ran 35000 miles on my 08 and I am a luggin along fool, all small town driving and I beat the shit out of it and never saw those lights. I just got on tonight to ask why now after my SB3250 install Im getting the lights? And I just turned the smarty up to 7 and beat on her and the lights come on. Sometimes once in a trip over 30 miles sometimes 4-5 times same trip.

I wonder if the whole clutch assembly puts out a specific harmonic vibration and pisses some sensor off? Im totaly lost on this one.....help

i had a guy that i sold a dd clutch to that didnt like the noise and vibration. he wanted a fluid damper and reported back to me after i sold him one he really liked it. he didnt have the light problem though. after thinking about this it could be a vibration thing tripping the lights.:tu:

so u think a fluid damper might be the trick

I wonder if this issue might have something to do w the transfer case or the 4x4 module. Could be totaly random and one time but I was in the snow luggin, needed 4 wheel, turned the knob and the lights came on, the whole time they were on she wouldnt go into 4 high, lights off and she locked in........:argh: