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Discussion Starter · #1 ·
Took the boat out for the 1st time this year and I was unimpressed with my truck's performance.

1) 10.5 MPG pulling only 5k lbs? Normally I'd get 16-17 mpg, probably more considering I wasn't driving through town. Part of the reason I bought a diesel was fuel milage while towing, this isn't any better than my old 1500.

2) There was something odd pulling the boat out of water, possible operator error and I'd like to hear your thoughts. Initially in 2WD, it felt like instead of being in gear the truck was in neutral. Pushed the gas, engine got loud, RPMs spun up, nothing happened. I considered the back end could be slipping since the rear tires were in the water but I didn't not hear what sound like spinning wheels, I didn't get any traction lights, and there was no fishtailing.

I put the truck into park, swapped to 4H, waited for the lights to stop blinking on the 4wd selector, and tried to pull out. Engine again revved up to about 1800 RPM without any movement. Just as it went above 1800 the truck finally began to roll.

Any ideas on these two issues?

Thanks
 

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Sounds like a torque converter; but that'd be pretty unusual for an allison behind a stock motor, especially as new as a 12'.
 

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Sounds like the hill assist is holding the breaks on. How was it after you got the boat out of the water?
 

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Discussion Starter · #4 ·
Sounds like the hill assist is holding the breaks on. How was it after you got the boat out of the water?
Hmm, this sounds interesting and certainly possible. Once it was rolling it pulled just fine. I didn't write it in my post, but I actually checked the parking brake 2-3 times because it felt like I was trying to drive with the brakes on. I'll have to get into my manual and see how hill assist is supposed to work. I will say I had no problem pulling away from any stoplights or out of my garage.

On 2nd thought, the truck did the exact same thing when I was backing out of the parking spot WITHOUT the boat on it. I had to do something of a 3 pt turn due to the parking situation, and when I tried to go forward (up the hill) the truck just felt stalled going back up hill.
 

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Discussion Starter · #5 ·
I cut and pasted from the manual, it should not be the hill assist feature:

"During the transition period between when the driver releases the brake pedal and starts to accelerate to drive off on a grade, HSA holds the braking pressure for a maximum of two seconds to ensure that there is no rolling. The brakes will automatically release when the accelerator pedal is applied within the two‐second window."
 

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Hill assist; hmmmm........ Learn something new every day!
 
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