2016 1500 - Tranny acts like it's in neutral going down hill?

BinghamtonEd · November 7, 2016

I have 1200 miles on my 2016 1500, 5.3 6-spd, bought it just under a month ago. I've had this happen on 3 separate occasions now. Each time the temperatures have been on the cold side, but not super cold (today was about 30 degrees, but its happened when it's been 45 out). Truck warmed up in the driveway for 5 minutes today before I started driving. I'm a relatively easy driver, I don't accelerate hard, I probably baby it more than I need to.

Cruising down moderate, not very steep, hill in our neighborhood around 20-25mph. Using the brakes lightly every couple seconds to maintain speed. When I get to the bottom of the hill where the road is level, and now need to use the gas, I press the gas pedal, and the RPM's shoot up to 4k or so, and there's no response in power. It seems like the transmission is not engaged, or is in neutral. When this happened this morning, and I let off the gas, tried again and got the same response. Then it happened again. Finally, after a few hundred yards, it started driving normally again on the fourth push of the gas pedal.

It also seems like when I drive up this hill, at 20 mph, it lacks power to maintain that speed, so I can gradually press the pedal more, and nothing happens, nothing happens, and then all of a sudden it shifts and speeds up. Not so much of a problem now, but when there's a few inches of snow on the ground, I'm worried it's going to lose traction.

Despite the other transmission issues that I see are common (occasional clunk when shifting, that's happened 3 or 4 times in the last month, and the throttle response in 1 & 2 sucks, but I'm learning to adjust my driving for that), I really like this truck. But, pressing the gas pedal a few times and not having the truck accelerate is ridiculous, and in certain situations, could be dangerous. I'm going to be taking this in to the dealer, but won't be able to do so for a week or two.

I tried searching online, and found a couple people commenting that something like this had happened on the 2014/2015, but I couldn't find anyone with a similar complaint on a 2016. Has anybody else experienced this?

1200 miles on this truck and it's already stressing me out.

TJay74 · November 7, 2016

Normal operation, if you are under coast conditions and or when the DCFO (deceleration fuel cutoff) tables are active the computer will engage the transmission into a neutral mode in order to conserve gas. The engine isn't really used as an engine brake anymore, you can thank the EPA for his. With the 6L80E/8L80E it is easier to do this since the transmission is a clutch to clutch transmission.

BinghamtonEd · November 7, 2016

Normal operation, if you are under coast conditions and or when the DCFO (deceleration fuel cutoff) tables are active the computer will engage the transmission into a neutral mode in order to conserve gas. The engine isn't really used as an engine brake anymore, you can thank the EPA for his. With the 6L80E/8L80E it is easier to do this since the transmission is a clutch to clutch transmission.

OK, I guess I can buy that reasoning, and I appreciate the quick response. If that's the case, then I have three follow-up questions :

1. Why doesn't this happen every time? I've down this hill at least 5 days a week for the 3+ weeks I've owned the truck, and it's only happened 3 times.

2. What does one do if they find themselves needing to accelerate while coasting down a hill?

3. What can I do differently at the bottom of the hill so that I'm not coasting for a few hundred yards revving the engine? I've tried tapping the brakes lightly, didn't seem to help, but if your response is correct, that would make sense.

Off of that issue, any suggestions as to going uphill and the lack of power, then too much power? Never had this problem with any of the other vehicles I've driven. Worried about snowy/icy conditions. Seems like maintaining a 20mph speed is troublesome.

truckguy82 · November 7, 2016

I have 1200 miles on my 2016 1500, 5.3 6-spd, bought it just under a month ago. I've had this happen on 3 separate occasions now. Each time the temperatures have been on the cold side, but not super cold (today was about 30 degrees, but its happened when it's been 45 out). Truck warmed up in the driveway for 5 minutes today before I started driving. I'm a relatively easy driver, I don't accelerate hard, I probably baby it more than I need to.

Cruising down moderate, not very steep, hill in our neighborhood around 20-25mph. Using the brakes lightly every couple seconds to maintain speed. When I get to the bottom of the hill where the road is level, and now need to use the gas, I press the gas pedal, and the RPM's shoot up to 4k or so, and there's no response in power. It seems like the transmission is not engaged, or is in neutral. When this happened this morning, and I let off the gas, tried again and got the same response. Then it happened again. Finally, after a few hundred yards, it started driving normally again on the fourth push of the gas pedal.

It also seems like when I drive up this hill, at 20 mph, it lacks power to maintain that speed, so I can gradually press the pedal more, and nothing happens, nothing happens, and then all of a sudden it shifts and speeds up. Not so much of a problem now, but when there's a few inches of snow on the ground, I'm worried it's going to lose traction.

Despite the other transmission issues that I see are common (occasional clunk when shifting, that's happened 3 or 4 times in the last month, and the throttle response in 1 & 2 sucks, but I'm learning to adjust my driving for that), I really like this truck. But, pressing the gas pedal a few times and not having the truck accelerate is ridiculous, and in certain situations, could be dangerous. I'm going to be taking this in to the dealer, but won't be able to do so for a week or two.

I tried searching online, and found a couple people commenting that something like this had happened on the 2014/2015, but I couldn't find anyone with a similar complaint on a 2016. Has anybody else experienced this?

1200 miles on this truck and it's already stressing me out.

that has never happened to me. Transmission revving up would scare me.

Also sounds like a loose pedal is another issue.

Push your throttle in with your hand, many people including myself have noticed a half inch or more of dead throttle travel from the throttle assembly itself flexing. Some of us have stuck a paint stick behind it, or have taken it out the assembly and put something like a piece of a mudflap behind it. It makes a big difference if you have a flexing assembly.

truckguy82 · November 7, 2016

Just to be clear, the coasting and revving thing is not normal at all.

glcbn · November 8, 2016

I have a '14 and what the OP experienced is pretty much what happened to me. Only once though....so far. I've went down this particular hill many times. It's very steep and starts from a dead stop at a 3 way intersection. I never give it gas. I just let it coast and by the time I'm at the bottom,speed is usually 45 to 50. Then you start a climb up a much more gradual incline. Wife was in the truck with me and we were talking. I realized after a few seconds we were not accelerating and the tach needle was almost 5,000........OUCH!! Put it in neutral then back in drive and all was fine. I've been down that same hill 4 or 5 more times since and no issues. Thinking trans just had a brain fart that day.

redwngr · November 8, 2016

Just to be clear, the coasting and revving thing is not normal at all.

Agree 100%.

Clearly there is something wrong if it freewheels when the throttle is applied as described.

glcbn · November 8, 2016

Agree 100%.

Clearly there is something wrong if it freewheels when the throttle is applied as described.

If the transmission is "stuck" (for lack of a better description) in neutral (in between gears, whatever it may be) when the throttle is applied, then it is pretty much 100% normal.

BinghamtonEd · November 8, 2016

If the transmission is "stuck" (for lack of a better description) in neutral (in between gears, whatever it may be) when the throttle is applied, then it is pretty much 100% normal.

That would be the 'normal' operation if the transmission was not in gear, but wouldn't the 'normal' operation of the transmission include it not getting stuck out of gear?

glcbn · November 8, 2016

That would be the 'normal' operation if the transmission was not in gear, but wouldn't the 'normal' operation of the transmission include it not getting stuck out of gear?

I see what you're saying, as that is definitely not normal operation. But as TJay posted, the trans does infact go into neutral mode under certain conditions. It not returning to normal "drive" mode quickly enough, or worse case, not at all without you/me the driver intervening sotospeak seems to make it an issue.