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Looking for first hand info towing with the new 2500 HD wIth the 3:42 rear end and 10 speed tranny. Has anyone trying pully steep grades with this setup? I currently use a 2015 2500 HD LTZ and have been very satisfied with it. Looking to purchase a new truck and leaning towards a 2019 as I know the set up. I am afraid with the new setup it will not pull mountains as well and the tranny will be constantly shifting. Also as a follow up...is the fuel MPH reall improved with this setup? Last time they did this to the 1/2 ton gas the mileage actually went down a bit in real life.
 

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I've pulled a 9k toy hauler with my 2500 through Oh, Md, Pa, Va and WV. Tow haul mode and cruze control at 70 mph for all but the steepest climbs. The 10 speed was great. Always seemed to be in the right power band and averaged 9-10 mpg.
 

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Even pulled well on secondary roads? I pull some steep mountain ares here in WV that are not interstate with ~15000 lbs toy hauler when fully loaded. 9-11 is about what I get for mileage while towing on the interstate without the tow haul mode so I guess no real difference there. So your saying the transmission holds well and doesn't do a lot of back and forth shifting while driving or towing over hills. What kind of mileage do you get without towing?
 

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No problem on secondary roads either. My normal run puts me on back roads for about an hour between Cumberland Md and Winchester Va. The shift points are so close together its hardly noticable. Stayed between 1600-2000 RPMs for the most part. I came from a 6.0 gasser and that always seemd to be searching on the back roads. It would either hold the gear too long and push the RPMs up unless I took it easy up the hill. Interstate was fine, back roads lacked the torque to maintain speed up the hill.

On the highway I normally get 19-20 @ 75-80 mph. I do better on back roads, probably because my speed is reduced. Normally 21-22 on relativly flat ground unless there are a bunch of stop lights/signs.
 

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Even pulled well on secondary roads? I pull some steep mountain ares here in WV that are not interstate with ~15000 lbs toy hauler when fully loaded. 9-11 is about what I get for mileage while towing on the interstate without the tow haul mode so I guess no real difference there. So your saying the transmission holds well and doesn't do a lot of back and forth shifting while driving or towing over hills. What kind of mileage do you get without towing?
On the subject of pulling power, not controlling stability, that 15k lbs is only 40-50% the capacity of a 3500 DRW that shares the same drive train as a 2500. The only difference being that a 3500 DRW can control more weight. 15K is no big deal for the engine and transmission.
 

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Thanks. I was never concerned with the towing capacity of the engine as I have a 2500HD Duramax now. My main concern is the 3:42 rear end with the ten speed. To me with higher gears in rear end and a tranny with so many levels of shifting that I figure every time you even touch the fuel pedal it would start shifting and with a load on it would be even worse. When I test drove one of the 1500 trucks they took from the 3:73 rear end and put in 3:08 standard gear set It shifted so much I took it straight back before the tranny wore out. Got the 3:42 which was an option with the trailer package. Still did not work as well as the 3:73 of course and you could tell a difference. Just wanting to know the HD isn't falling into the same trap.
 

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Thanks. I was never concerned with the towing capacity of the engine as I have a 2500HD Duramax now. My main concern is the 3:42 rear end with the ten speed. To me with higher gears in rear end and a tranny with so many levels of shifting that I figure every time you even touch the fuel pedal it would start shifting and with a load on it would be even worse. When I test drove one of the 1500 trucks they took from the 3:73 rear end and put in 3:08 standard gear set It shifted so much I took it straight back before the tranny wore out. Got the 3:42 which was an option with the trailer package. Still did not work as well as the 3:73 of course and you could tell a difference. Just wanting to know the HD isn't falling into the same trap.
You can't really compare the diff gearing between trucks unless you're sure the transmission gearing is similar. I don't know what the gear ratios for the lower gears are in the 10-speed but if the transmission has more gear reduction than the six-speed then discussing 3.42 vs 3.73 isn't really useful. Better to determine the range of final drive ratios (highest and lowest transmission ratios multiplied by the diff ratio) and compare those.
 

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Yes, I was just looking for real life experience in the mountain areas as opposed to a computer simulation which was answered for the most part. Anyone can run around a test track and say it works great. You just never really know until you hook up a trailer and pull a mountain. I was just afraid with 10 speed tranny that it would be shifting a lot. Would be nice if they would bring back the manual tranny. Granted autos are rated a little higher in towing capacity. This may be a great setup. Time will tell.
 

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I would not place any bets on a manual coming to the GM DM trucks.
 

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Yes, I was just looking for real life experience in the mountain areas as opposed to a computer simulation which was answered for the most part. Anyone can run around a test track and say it works great. You just never really know until you hook up a trailer and pull a mountain. I was just afraid with 10 speed tranny that it would be shifting a lot. Would be nice if they would bring back the manual tranny. Granted autos are rated a little higher in towing capacity. This may be a great setup. Time will tell.
It's SUPPOSED to shift a lot to keep it in the powerband. That's the whole point of a 10 speed transmission. That's why semis have 18 gears. The 10 speed has a very low first gear that makes the final drive lower than the 3.73 that your used to, to get it out of the whole. After that, the rear end makes no difference.

It will pull better than you're used to. How durable the 10 speed is compared to the 6 speed, no one knows yet.
 

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It's SUPPOSED to shift a lot to keep it in the powerband. That's the whole point of a 10 speed transmission. That's why semis have 18 gears. The 10 speed has a very low first gear that makes the final drive lower than the 3.73 that your used to, to get it out of the whole. After that, the rear end makes no difference.

It will pull better than you're used to. How durable the 10 speed is compared to the 6 speed, no one knows yet.
Thanks for posting this. I was going to say the same thing but the OP likened multiplying gear ratios to a "computer simulation" so I figured it would likely fall on deaf ears.
 

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To their credit, autos get better fuel economy and can maximize performance. But it does take away a certain "in control" feeling. Also- while I prefer autos, I like to have a choice as well.
 
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