Let me throw in on this fwiw ... just the facts ... sort of ,,, we tow a 16ft
Scamp with a 2004 Chevy Colorado ext cab 5 spd ,2.8 liter 4 banger. Not exactly your rig but maybe my numbers will help with your decision.
The Colorado is rated to tow 4000lbs but that's with the 3.5 liter engine BUT the owners manual says that the 4 cyl 2.8 liter engine and 5 speed manual with the 3.42 rear gear should only tow 1700lbs. Just changing the rear gear to 3.73 raises the towing capacity to 2200lbs??? but the heavier crew cab 4wd automatic with 3.5 liter can tow 4000lbs?
Anyway, the door sticker on my truck says the GVWR is 5000lbs but the front
axle is rated at 2533 and the rear
axle is 2896 so what does that mean? The combined F+R is 5429lbs??? I guess then that the GCWR would be 5000 + the 1700lb trailer, right? 6700lbs? Ok maybe 5429+1700 = 7129?
Wrongo, the GCWR in the owner manual is 5500lbs, huh? that's a 500lb trailer??? Actually that's a 500lb total payload? Meanwhile the heavier crew cab 3.5 liter automatic has a GCWR of 9000lbs ... Doesn't seem right but then engineers figure this stuff so who am I to argue that the numbers don't jibe.
Anyway the actuals that I tow with probably violate these numbers but here they are;
Front
axle 2180
Rear axle 2680
Trailer axle 2080
GCVW 6940 (I'm guessing my trailer tongue-weight at 325lbs by bathroom scale)
These numbers (excepting tongue weight) come from a certified sale at a truck stop. We took the weights just as we left on a trip to Massachusetts from Florida this month. The scale weighs all 3 axles at the same time with passengers. That's empty water and holding tanks (except HW tank), loaded with food and supplies but the fuel tank on the truck was full. Last year my numbers were higher. We left some stuff home this year. We have a pretty much standard
Scamp without
propane but with a dorm size
fridge,
microwave, hot water heater, shower, built in potty, air conditioner, spare tire, bag
awning and a tongue box with a
battery. Also we have a
fiberglass cap on the truck bed.
We have electric brakes on the trailer and a frame hitch rated at 3500lbs. We have new Carlisle trailer
tires (13") and run them at maximum. The truck
tires are a couple of years old but in excellent condition. I run the rears at max pressure (42psi) and the fronts slightly lower at 35 psi.
This year we tried an experiment and kept our speed to a maximum of 55mph. The truck and trailer performed flawlessly. We took the mountain route (I-81) instead of I-95; stopping for fuel, lunch and overnight 2 nights. 1500 miles give or take.
We averaged just over 20 miles per gallon. That compares to last year when we ran the same route but went 65 to 70 mph and got barely 15 mpg.
I thought that the fuel economy would suffer in the mountains with all the down-shifting and pedal to the metal type driving but no, the fuel economy never varied more than a few tenths for the whole trip whether on the flat or not.
Now I might be putting strain on the truck that will shorten its life... maybe. BUT, the truck chassis is strong enough and heavy enough to tow 2000lbs other wise it wouldn't rate a 4000lb trailer just by changing the drivetrain. Also the trailer capacity difference just by changing rear gears seems unreasonable but then GM is probably guarding against warranty claims on the clutch.
The engine doesn't seem to mind chugging along at 1700 rpm doing 55 mph. It seems not to be lugging or straining at all. When a hill drops the rpm to 1500 or so I down shift but for the most part we cruise at 55 with the cruise control on in 5th gear.
Starting from a dead stop uphill is a strain on the clutch no doubt. We'll likely need to replace it sooner than we would otherwise. We try to avoid backing uphill from a dead stop but my driveway is like that and the rig does it but I have to feather the clutch more than I would like.
The truck has plenty of brakes although in the eastern mountains, they'll likely wear out sooner than normal too. I consider the extra wear on the clutch and the brakes as 'goes with the territory' ... oh well, thems the breaks.
I think our rig performs satisfactorily even if it is a bit on the chubby side.
That brings me to an opinion. My truck gets approximately 25% better gas mileage (whether towing or not) at 55 mph than it does at 70mph. Going 55 mph on the interstate might be a bit risky since everyone else is doing 75 and 80 mostly. If we're in the middle of an energy crisis that threatens to raise gasoline prices above $5/gallon here shortly, why isn't everyone conserving fuel by driving slower? I mean we were cruising quite comfortably in the right lane doing 55 but we were definitely in the minority as the Tahoes, Excursions, and 7 liter BMWs not to mention 18 wheelers went blasting on by. I know they can afford the gas but how does that give them the right to burn the gas I'll need next year?
As anti-Gummint as I am at times, I think the feds need to step in and reinstate the old double nickel speed limit. 25% less fuel consumption would bring an instant end to the fuel oil crisis. Ok I'd settle for a 10% saving. It's like we didn't learn anything from the oil embargo of the 70s. Meanwhile until the leadership steps up and convinces everyone such steps are necessary, the rest of the stuff about fluorescent
light bulbs,
solar cells, global warming. greenhouse gasses, drilling in the Gulf of Mexico, etc, etc. is just so much smoke and mirrors.
1975 Trillium 
Trillium in hybernation
Linear Mode
