New Truck question(s)

[marpel]

Good day,

As my current truck has reached it's retirement, I am beginning to look at a new vehicle.

We have a relatively small trailer (22' and about 5k lbs loaded) and have been towing it with a GMC Sierra, 6.2L, 6spd, 373. On short trips it has been a fine combo.

However, since the birth of a grand-daughter in Denver Co, we have spent every vacation driving back/forth from BC, Canada, via various interstates, with speed limits at 60/70/80, depending on location. And anticipate this will continue for a good number more years.

Currently, pulling at 63-64-ish, I put it in 5th, as in 6th it will constantly downshift at even the slightest incline/overpass. Much (like 80%) of the route is like this. Of course, up hills/mountains is understandably different.

I am considering going up in size to a 2500 or 3500 with the 6.6L gas, not diesel (may upgrade trailer in future), and am wondering if this would allow pulling in overdrive, rather than in 5th, during those long straight stretches. I am also considering the Ford 7.3 but think it may be a bit overkill for my needs, although it remains an option.

Any other thoughts would also be welcome.

Many thanks,

Marv

[blt2ski]

You don't need to go lower than a 3.42 with the newer transmissions.
The 6 sp has a 4-4.1 first gear. 8 sp about 4.3, 10sp 4.5-1. The 8 & 10 sp has an overall low gear ratio lower than a 6sp/3.73 setup. Plus a slightly tall final drive, closer spaced gears, better power to ground etc.

Marty

[Bassin_Bob71]

The other thing I would add is I think the lowest rear end you can get with a 6.2 10 speed is a 3.42. No 3.73 offered and I'm told with the 10 speed, the 3.42 is plenty. All 6.2's from 2014 and later are rated at 420hp and 460tq. Good luck with the search.

[Bassin_Bob71]

Just to clarify, you didn't say what year your truck is but unless its a 2014 (the only year you could get 420 hp 6.2 with a 6 speed trans), its likely the older LS based 6.2 with 403hp and 417tq. I had one of those and now how have 2015 6.2 (420hp) with the 8 speed and it tows much better.

My 8 speed with the most recent fluid change works well, but everything I read and hear is the 10 behind the 6.2 which started production in 2019 for the trucks is awesome.

Bob

[Grit_dog]

marpel wrote:
So, my choices are:

GMC Sierra 1500 6.2L 3.73 420/460 DFM (don't want DFM) 26gal. One of the more pricier choices.

GMC Sierra 2500HD 6.6L 3.73 401/464 36 gal. Middle of the road in price.

Ram 2500HD 6.4L 3.73 410/429 31 gal. Weird thing is, the model is Big Horn, but can't seem to get Big Horn package with crew cab and 6 1/5 ft bed. So, one of the more pricey, comparable to the Sierra 1500.

Ford 2500HD 7.3L 3.55 430/475 36 gal. Cheapest (by about 4K pre-tax).

All are about the same size, within an inch or so in every dimension, and within a couple hundred pounds in payload and towing - with Ford leading the pack but not by much. The 1500 is smaller by a bit, quite far behind by at least a thousand in payload and 2500 in tow, and does not have an HD engine, of course.

Although we will be looking at getting a bigger trailer, I doubt we will get even close to 3500 territory, which is why I listed the 2500s.

Regarding mpg, while I, like everybody, would like to get super decent mileage, a decent ride and tow is priority.

Thanks to everyone, I have been learning a lot.....but still can't figure out why the smallest(L) engine has more hp/torque than the bigger HDs. Go figure.

Marv

Understand that ANY 3/4 ton will have far more useable payload than any 1/2 ton, contrary to the "ratings". And most srw 1 tons only have more payload due to heavier rear springs, ret of the chassis is the same as a 3/4 ton, except in the very upper end where some 3/4 tons have a slightly smaller rear axle (like 9000lbs vs 10000 or similar).

Not that a 1/2 ton is incapable, but in broad strokes, 1/2 ton is a completley differnt truck than the HDs and 3/4 and 1 ton are very similar.

[ib516]

marpel wrote:

Thanks to everyone, I have been learning a lot.....but still can't figure out why the smallest(L) engine has more hp/torque than the bigger HDs. Go figure.

Marv

The HD engines will make more hp and tq at lower RPM by design. It's not all about peak numbers. They often have been engineered with more durability, better cooling, and longevity higher up on the priority list as engineering goals as well as they are used in HD applications.

[ib516]

JMHO, but any of the three 3/4 tons would do the job nicely. Pick the one you like best.

I'd skip the 1500 series just because of the chassis limitations. the GM 6.2L is a very strong engine.

[wing_zealot]

marpel wrote:
Thanks to everyone, I have been learning a lot.....but still can't figure out why the smallest(L) engine has more hp/torque than the bigger HDs. Go figure. Marv

Turbos

[marpel]

So, my choices are:

GMC Sierra 1500 6.2L 3.73 420/460 DFM (don't want DFM) 26gal. One of the more pricier choices.

GMC Sierra 2500HD 6.6L 3.73 401/464 36 gal. Middle of the road in price.

Ram 2500HD 6.4L 3.73 410/429 31 gal. Weird thing is, the model is Big Horn, but can't seem to get Big Horn package with crew cab and 6 1/5 ft bed. So, one of the more pricey, comparable to the Sierra 1500.

Ford 2500HD 7.3L 3.55 430/475 36 gal. Cheapest (by about 4K pre-tax).

All are about the same size, within an inch or so in every dimension, and within a couple hundred pounds in payload and towing - with Ford leading the pack but not by much. The 1500 is smaller by a bit, quite far behind by at least a thousand in payload and 2500 in tow, and does not have an HD engine, of course.

Although we will be looking at getting a bigger trailer, I doubt we will get even close to 3500 territory, which is why I listed the 2500s.

Regarding mpg, while I, like everybody, would like to get super decent mileage, a decent ride and tow is priority.

Thanks to everyone, I have been learning a lot.....but still can't figure out why the smallest(L) engine has more hp/torque than the bigger HDs. Go figure.

Marv

[Grit_dog]

ib516 wrote:
So shooting for running in the highest gear is really no goal to shoot for.

100% true

[ib516]

I had a Ram 2500 with the 6.4L Hemi and 4.10s that I pulled a 37 foot 5th wheel with. It would not run in 6th (same as you) unless I had a heck of a tail wind. It would run in 5th or 4th however, with a decent RPM spread between the two. The reason I am telling you this is because running in 4th (higher RPM) or 5th (lower RPM) didn't make much difference on the "instant" mpg display. So shooting for running in the highest gear is really no goal to shoot for.

Now, if the only way you can pull a load is with the engine screaming near redline constantly (not just during up grade pulls)_that's different. But I really don't think you're going to gain much making the swap you are considering. I'm no diesel fan boy, but it's simply a fact that they pull heavy loads much easier, and at lower RPM, and will get better mpg when comparing apples to apples. I lost about 20 to 25% going from the Cummins to the Hemi, but was still very satisfied.

The 2500 series truck is much better suited to towing, but you won't notice a huge difference in power, though there will be an increase.

[dodge_guy]

Whatever you get, get the lowest gear available. this will allow towing in OD with the weight you are saying.

[fla-gypsy]

No one mentioned rear gear ratio which is as important as torque and transmission if you are towing and don’t want to be hunting a lower gear all the time

[APT]

Get the 3/4 ton for much larger fuel tank. If you like the Ford better and it's cheaper, buy that 7.3L/10-speed. Overkill? No one said than when towing a TT. More power and more gears typically means lower fuel consumption and better towing experience, power when you want it.

[Sjm9911]

Without having driven them all, the 6.6 is so far a prety decent truck. I would price some out in your area. I got the chevy because it was cheaper and more readily available then the gmc. My last 2 trucks were new gmcs. Just looking around, and depending on options, a lt 4x4 2500 chevy can be had for 51000 around my area. Not sure if you can talk them down now adays. Look around, price them out and sit in them. Then decide. Any would be more then adequate for your TT.