I just re-read you first post, same here.

We have a Correct Craft Martinique, weighs 3200lbs then add the dual axle trailer and all the other things in the boat and its up around 5,000lbs. My burb struggles going up the huge hills on my way to NH from NY. But if i let it rev in 2nd gear at around 4500 rpm then it can maintain 65~70 mph with out much difficulty, but the gas mileage does suck.

But you could do a motor swap on your 1500, the 6.0L is the exact same motor just with larger bore and longer stroke, then you could throw on a LS1 intake, light cam, and aftermarket exhaust and bam! heaps more power! The LS motors truely have great potential and are just so common they are very cheap to upgrade, they are so common and easy/cheap that Chrysler and Ford people use them in off roading, rat rod, racing, and a whole bunch of other stuff

 

So, if you go with a 2500-3/4 ton, you will feel like it's "cutting it" as opposed to "not cutting it", but, as far as being "significantly" better on mileage...no.

PS:
The reasons for being able to "cut it" are as stated...
Heavier Vehicle,
Bigger Engine,
Heavier Transmission,
Geared to better handle loads as you require.

Simply a more robust vehicle.

 

oh and best place to find em'. Texas. Lived there for 8 years, prob 9 out of 10 house had em'. (i moved in 2009, right when economy really tanked) they are so common its not even funny, any year, any package, and 1500's as well a good amount of 2500's. And even better, THEY ARE IN GREAT SHAPE! So many people took them right to the local dealer ship to have work done, very good dealership, many knowledgeable mechanics who knew what they are doing.

 

SWHouston.

The motor is the same, just slightly larger displacement, transmission is the same, just better cool capacities, suspension, stiffer and will not sit way down like 1500.

But over all a 2500 is much better.

My 1500 had the U joints go last summer, just today BOTH cv joints started grinding like crazy. great...

the 2500 has many things upgraded to allow it to tow better, if i had the 6.0L my burban "could" tow 9,600lbs just like the 2500. but the 2500 would smoke me! I would have so many things breaking, overheating, etc if i tried to tow that much.

 

The reason the 09 6 spd feels doggy from a dead stop isn't because of the 6 spd. It's caused by "torque management" which prevents the throttle from opening as fast as your foot is telling it too. Think 5yr/100K powertrain warranty. Tuners can reduce it or eliminate it at your risk.

Doug Suburban: Are you using Tow/Haul mode pulling the boat?

 

hmmm ok. but really i havent heard anyone praise the 6 speed like people do the 4 speed. but i dont have one so i cant really tell.

Me personally i only use tow haul for getting up to speed. I really dont like the way it acts when im up and driving. it acts the same on tow haul with or with out a load. and driving with tow haul on makes it drive weird. idk. thats just me. also my biggest beef with it is it LOVES to jump into 2nd at the slightest incline when im in tow haul, it does it to often already with cruise control but when you have tow haul on its 4th gear down hill 2nd every where else, and 2nd gear at 75mpg, not so good. sometimes it will hold on to 3rd, but tow haul off it uses 4th and 3rd as it should. dont know why...

 

It reacts that way because that's the way the Tow/Haul mode is programmed. It prevents the engine from lugging when towing by downshifting when it wouldn't normally.

 

I agree, I wish mine was !

 

I have the 6spd tranny and I have no gripes in fact I think it causes the engine to rev less well towing, but that is comparing a 04 Silverado 1500 to the 2500 Suburban. Even the 09 F150 I owned in between the 2 chevys reved less with the 6 sp and 3.55 gearing than the 04 Silverado with 3:37 gearing and 4spd.

 

Yes - using this mode on long drives.