Weird Bog On '08 6.0l 2500 Truck When Turning & Accelerating

Pool Runner · March 24, 2010

Heres my current issue and it may just be a characteristic of the truck. If I am sitting at a light ready to make a right turn and get on the gas my truck sort of bogs for a second like there is no power then it takes off. I had another situation where I was coming off the freeway trying to make the light and turn left at the same time as I let off the gas as I slowed for the intersection then in mid turn since I was going up hill I got back on the throttle and it's as if the truck bogged the motor intentionally until I was straight? What gives.

txdutt · March 25, 2010

torque management that the GM nannies put in to the PCM

Gregorio · March 25, 2010

Sounds like you might have a failing front wheel sensor. My dad's 2006 Denali SUV started doing this recently. DIC flashes "Traction Active" or something to that effect. Impossible to diagnose as there are no codes being generated. As far as the system is concerned, it is working fine. You have a 50/50 chance if you try to replace just one at a time.

Big black truck · March 25, 2010

Its called Traction Control (ECS). If the car feels you are going too fast for a corner, it automatically slows you down safely. It also helps with wheel spin etc. I have a switch on my bmw, that allows me to disable it. I have disabled it to do a burn out before, but leave it on for the most part.

dataspng · March 26, 2010

If you have posi-trak / limited slip rear axel option, its wet pavement and your truck is empty it will do it every time! Hold the traction control button down for 15 seconds or so your dash will tell you its off (its not) but it helps with what your talking about. If you want to do burn outs it wont, its never really off unless you get it programmed out by a tuner (which voids warranty).

Whats a real bear is when you forget to turn it off, your towing something big up a hill on gravel (or anything slippery) and the dork managment (oops I mean torque managment) kicks in and chops the throttle, you loose all your momentum and presto your stuck! or worse the something heavy starts dragging you down the hill backwards (note: electric trailer brakes dont work backwards!). Now thats safe!

Gregorio · March 26, 2010

If you have posi-trak / limited slip rear axel option, its wet pavement and your truck is empty it will do it every time! Hold the traction control button down for 15 seconds or so your dash will tell you its off (its not) but it helps with what your talking about. If you want to do burn outs it wont, its never really off unless you get it programmed out by a tuner (which voids warranty).

Whats a real bear is when you forget to turn it off, your towing something big up a hill on gravel (or anything slippery) and the dork managment (oops I mean torque managment) kicks in and chops the throttle, you loose all your momentum and presto your stuck! or worse the something heavy starts dragging you down the hill backwards (note: electric trailer brakes dont work backwards!). Now thats safe!

That would be SURGE trailer brakes that do not work going backwards downhill. Electric trailer brakes work in both directions uphill and downhill.

When towing something uphill on gravel, why on earth would you want to turn off Traction Control? It is very effective at helping keep you from losing momentum. Take a truck like the Denali with traction control, open rear diff and 4Hi against a similar regular pickup without traction control, locking diff and 4Lo. The truck with traction control will walk up a slippery slope with ease while the other truck will slip and slide but go nowhere. I've got both and right now when the trails around here are still covered with weeds and wet dirt, the only vehicles that can make it to the top are those with traction control.

I agree that GM's torque management goes way too far at limiting power availability.

dataspng · March 30, 2010

That would be SURGE trailer brakes that do not work going backwards downhill. Electric trailer brakes work in both directions uphill and downhill.

When towing something uphill on gravel, why on earth would you want to turn off Traction Control? It is very effective at helping keep you from losing momentum. Take a truck like the Denali with traction control, open rear diff and 4Hi against a similar regular pickup without traction control, locking diff and 4Lo. The truck with traction control will walk up a slippery slope with ease while the other truck will slip and slide but go nowhere. I've got both and right now when the trails around here are still covered with weeds and wet dirt, the only vehicles that can make it to the top are those with traction control.

I agree that GM's torque management goes way too far at limiting power availability.

Really? - Say that to passenger (wife) screaming in my ear as truck was doing its "traction control" management of "throttle on" "throttle off" no power as it was sliding backwards being yanked back down a steep gravel road with a flatbed with a John Deere tractor on board. It was my fault, forgot to turn off the traction control and if I had remembered I would of made it like I have a dozen other times with this truck and 1000 times with my older truck that didnt have all the nanny safety stuff.

I agree with you - actually we have played on a hill on our property doing just what you said... An older truck with out traction control and new with and yep, the truck with traction control will "walk" itself up the hill father then the one spining all the way. But you throw in trailer that weighs more than your truck (but not over its towing capacity) and momentum is your friend and chopping the throttle kills that real quick. Just goes to show the folks pushing for all the safety nanny garb do not know all the combinations of how we use our trucks and can actually make some of them more dangerous. Of course since it had the button to turn it off and I forgot its my fault which make for a poor lawsuit which is another goal of the safety fluff.

I must have older style electric brakes on my trailer, they are not designed to work backwards and they dont. The brake shoes are about due again I may look into an upgrade that works both ways...

Thanks

Gregorio · March 30, 2010

That would be SURGE trailer brakes that do not work going backwards downhill. Electric trailer brakes work in both directions uphill and downhill.

When towing something uphill on gravel, why on earth would you want to turn off Traction Control? It is very effective at helping keep you from losing momentum. Take a truck like the Denali with traction control, open rear diff and 4Hi against a similar regular pickup without traction control, locking diff and 4Lo. The truck with traction control will walk up a slippery slope with ease while the other truck will slip and slide but go nowhere. I've got both and right now when the trails around here are still covered with weeds and wet dirt, the only vehicles that can make it to the top are those with traction control.

I agree that GM's torque management goes way too far at limiting power availability.

Really? - Say that to passenger (wife) screaming in my ear as truck was doing its "traction control" management of "throttle on" "throttle off" no power as it was sliding backwards being yanked back down a steep gravel road with a flatbed with a John Deere tractor on board. It was my fault, forgot to turn off the traction control and if I had remembered I would of made it like I have a dozen other times with this truck and 1000 times with my older truck that didnt have all the nanny safety stuff.

I agree with you - actually we have played on a hill on our property doing just what you said... An older truck with out traction control and new with and yep, the truck with traction control will "walk" itself up the hill father then the one spining all the way. But you throw in trailer that weighs more than your truck (but not over its towing capacity) and momentum is your friend and chopping the throttle kills that real quick. Just goes to show the folks pushing for all the safety nanny garb do not know all the combinations of how we use our trucks and can actually make some of them more dangerous. Of course since it had the button to turn it off and I forgot its my fault which make for a poor lawsuit which is another goal of the safety fluff.

I must have older style electric brakes on my trailer, they are not designed to work backwards and they dont. The brake shoes are about due again I may look into an upgrade that works both ways...

Thanks

I guess the loads I've been towing up slippery slopes are not great enough to cause the truck to bog down. Usually, they are around 5K and even though it is a awkward movememnt, it seems to power up the hills just fine. A bigger load would surely be a problem especially without the torque multiplying low range TC. The regular truck is a white knuckle ride with a lot of speed and butt pucker! I'm sure more tongue weight or more payload would help the rears get traction.

Your trailer must be an ancient artifact. I though I had the oldest one still on the road! It was built in the mid 70's and the drum brakes work in both directions. They don't stop like my new trailer with 4 wheel disks but they grab enough in reverse to remind me to turn down the bias when backing up. I'd be scared to drive it up a hill like that if it didn't! Talk about pucker!

Rat4go · March 31, 2010

Heres my current issue and it may just be a characteristic of the truck. If I am sitting at a light ready to make a right turn and get on the gas my truck sort of bogs for a second like there is no power then it takes off. I had another situation where I was coming off the freeway trying to make the light and turn left at the same time as I let off the gas as I slowed for the intersection then in mid turn since I was going up hill I got back on the throttle and it's as if the truck bogged the motor intentionally until I was straight? What gives.

The sag during a step-in during a rolling turn is probably you stepping on the throttle when the trans is in the middle of a coasting downshift. I have had some conversation with someone who should know and he says that stepping into a downshift that was started when the throttle was closed can cause this as if the torque isn't 'managed', the downshift that was in-process would feel really bad (it would slip) since the pressure that was going to the clutch was set up for the torque at closed throttle when the shift started.

I can't comment on the standing-start issue, but traction control seems to be suspect based on the comments from others.