6.6 gas, 373 or 342, 2500 or 3500

[JFF&KRN]

Just putting some feelers out there. if you have a gas, GM, 6.6 with 373 or 342 and towing about 14K, let me know how you like it or don't like it. thanks

 

[Joe1967]

I don't own one, but would go for the 3500. More payload capacity, and not much different a ride. Those rear gears are so close you are only talking about a couple hundred of RPM difference. If your trips are short, go for gas. If you are driving around the country, I would go for diesel. Easier to fuel at fueling stations, twice the torque, and better mileage. My $.02 from experience. Are you looking at new or used? The new has the 10 speed, which basically makes the rear end gearing a mute point.

 

[BobLandry]

With a trailer of that size, I would definitely go with a diesel 3500 and probably a dually.

 

[Redapple63]

With a trailer of that size, I would definitely go with a diesel 3500 and probably a dually.

Agree, 14k is my personal cutoff between single and dual rear wheel diesel. Again my personal cutoff.

In the past I considered about 8-9k limit for gas, with the new breed of gas trucks out today, I would bump that to 10k. Depending on the service duty aka how often, how far and what type of roads that could also go up or down a bit.

My personal take is you are solid into diesel territory and bordering on DRW diesel.

Good luck with your decision!

 

[Wynn1427]

I believe 3.73 is for Gas and 3.42 is Diesel for GM HD trucks.

Information from https://www.gmfleetorderguide.com/
https://www.dropbox.com/s/hbjzf1t2fiddlqu/2022_2500HDprintbook.pdf?dl=0
https://www.dropbox.com/s/anlbzzylp0zvrpa/2022_3500HDprintbook.pdf?dl=0

Cant comment on gas as I never had a gas HD one and was not even on my radar when I went shopping. Double check the trailering sticker on the door jamb if you can find a comparable one to get rough idea of capacities if you are ordering. Numbers in printbook are base before full build out and probably only numbers dealer will give you if you ask. One number I found interesting was limit on max tongue weight on stock oem gooseneck prep was only 3180lb, when back calculated to trailer pin weight of 20%-22%-25% yields 15,900lb-14,500lb-12,720lb and appears to be another limit check for the SRW along with payload. Also looks like GM has different GVWR between gas/diesel in specs so not sure how that works with the old gas gives me more payload discussion, maybe a GM derate gas for license fees?

 

[Redapple63]

I believe 3.73 is for Gas and 3.42 is Diesel for GM HD trucks.

Information from https://www.gmfleetorderguide.com/
https://www.dropbox.com/s/hbjzf1t2fiddlqu/2022_2500HDprintbook.pdf?dl=0
https://www.dropbox.com/s/anlbzzylp0zvrpa/2022_3500HDprintbook.pdf?dl=0

Cant comment on gas as I never had a gas HD one and was not even on my radar when I went shopping. Double check the trailering sticker on the door jamb if you can find a comparable one to get rough idea of capacities if you are ordering. Numbers in printbook are base before full build out and probably only numbers dealer will give you if you ask. One number I found interesting was limit on max tongue weight on stock oem gooseneck prep was only 3180lb, when back calculated to trailer pin weight of 20%-22%-25% yields 15,900lb-14,500lb-12,720lb and appears to be another limit check for the SRW along with payload. Also looks like GM has different GVWR between gas/diesel in specs so not sure how that works with the old gas gives me more payload discussion, maybe a GM derate gas for license fees?

Interesting information. My 2019 GMC Duramax has 3.73.

 

[Bamaman]

The 14,000 lb. fifth wheel is more trailer than a 3/4 ton will handle. That's where a dually is warranted. And if you're towing very many miles or in demanding terrain, a diesel is preferred.

The 6.6 GM engine for a load over 11K would need the lowest gear ratio the factory builds.

I have a diesel 3/4 ton crewcab, and I'm max'd out with a 11K lb. dry weight fifth wheel with a 2K kingpin weight.