I have a 2001 Sierra 2500 HD w/ the 8100 big block & Allison trans. It does not have a throttle cable, it operates by a throttle control sensor, in case that's relevant to the problem I'm experiencing. This problem began about a month and a half ago (July '05) quite infrequently at first (approx once a month) but has now progressed to almost once daily. Also, it occurs only in the afternoon on hot days, never in the morning or on days that are cool, (cool by Arizona standards). Also, it seems to happen within 2-3 miles of my start point, and only at highway speeds; it hasn't occurred on surface streets yet. I will be driving along, then it feels like I suddenly took my foot off the accelerator, the BATTERY light comes on, and the tach drops to zero simultaneously. The first few times this happened, it lasted only 3-4 seconds, then resumed acceleration, the BATT light went off & tach read normal, all simultaneous again. Now when it happens, it doesn't resume itself. It cuts off, (the truck actually quits running) I have to shift to neutral (otherwise the trans slows me down very abruptly) and coast off the highway, steering hard because I lose the power steering. This scares me because if it starts up on it's own again like it was first doing, I will get power steering back and am afraid to be oversteering when it kicks back in. After I stop, I shift into park, turn off the ignition and turn it back on. The truck runs fine all the way home. (Approx 25 miles) I have brought the truck to a GMC dealer and they have scanned the ECM and BCM for any codes that might have stored, but there were no codes. Suppossedly no bulletins, recalls, etc...either. But unless it actualy acts up for the technician, they cannot diagnose the problem. Has anyone else had this problem, or have any suggestions? Please don't suggest battery, cable connections or corrosion, that's all been checked. Any OTHER suggestions that may help?? Please? -Kristine[/size][/size][/size][/size][/size]

 

is it cutting out at cruiseing speeds or durring acceleration? if during acceleration a common problem is the alternator over charges which send the computer system into a closed loop mode which is when the stall occurs.

 

It cuts out at cruising speed, not acceleration. It cuts out when cruise control is on or off, it doesn't seem to matter.

 

it has to be an electrical problem somewhere. the only thing to do would be find a lab scobe that you can keep pluged in for a day to record all of the data being processed.

 

I had a similar situation with a '96 Silverado. My issue only occured while using the cruise control. The module was replaced and I haven't had the issue since.
By the way, I'm looking at an '01 Sierra HD 2500 with the big block like you have and was curious about its performance (dependability) and gas mileage. I'm sure the mileage isn't far into the double digits, but the truck is really nice and I love the power.

Good Luck,

 

Newbie here...stumbled across this thread and since Tissy's truck specs and problems are the exact same as mine, I was wondering if there has been any new information out there. I'm searching old threads, but not seeing anything that describes my problem as well as this thread does.

I hate the thought of having the horse trailer hooked up and having this happen on the freeway.

Thanks!

 

i'm new as well...actually just signed up because this problem started on my 2002 silverado 2500HD this past month, its done it twice only when cruise control is on driving on the highway. I've got 163,000 miles on it with the 6.0liter engine.

rodeogmc...sounds like all we can do is replace the cruise control module...i'm going to wait until the problem gets worse. i think the module is like $250.

 

What i think it is fuel pump getting hot / cutting off. Have a chevy , mine acted same way , quit crank right back, run half hour quit ect. I had fire , fuel soon as it quit it would crank right back up . About drove me crazy , thought if it would quit for good i could figure it out, but no. Changed pickup module/ ign. module, no. So i ran a fuel pressure check on it , had to watch it closely . But i caught it, drop in pressure a few seconds before it quit. Fuel pump. And to beat it all mine had 163k on it ,had original pump. Have a pressure check done.

 

NHTSA ID: 07V521000 Issued: No. of vehicles: 00011974
Engine and Engine cooling on certain pickup trucks equiped with the 8.1L V8 Engine, the crankshaft position can operate intermittently or fail completely. If the sensor operates intermittently, the SES light may illuminate and the Vehicle may run rough. The Engine may stall, and if so, may Re-start immediately or after a Cool down period. If the sensor becomes completely inoperative, the Engine will quit running and will not Re-start. Either of these failures can increase the risk of a crash. Dealers will replace the crankshaft position sensor free of charge. The recall is expected to begin during December 2007. Owners may contact Chevrolet at 1-800-630-2438 and GMC at 1-866-996-9463.

http://ww2.justanswer.com/uploads/Bl...sor_recall.pdf

 

the fuel pump thing is good to know, but my truck never stops running. the cruise control pops off the battery light comes on and the airbag light as well as other dash lights (like when you start the truck). its like a sure to the electrical system or a crash and its resetting itself. the second time it happened my cruise control didnt work until i stopped for gas and restarted my truck. i'm putting 500+ miles on it this weekend and will see if the problem persists. Again, to date its only happened twice.