Page 13 of the 2015 GM Towing Manual states that my 3500 EWB 6.6 Duramax can tow 9,700 lbs with the 3.54 gear ratio; when converted to 4X4, gearing was changed to 3.73. If I understand gearing correctly, I should be able to tow more with the higher gear ration but, how much more? Does anyone know of a chart or formula out there to answer this question? I am in the market for a travel trailer to go full-time with the family and want to make sure I don't buy something I can't tow. Thank you.

 

Towing is about being able to stop, not what you can pull. If you put larger brakes on then you should be able to tow more.

 

 

Mine is a 3500. My towing capacity is 10,000lbs. 3000lbs more than a 1500/2500.

I am not sure you are going to really gain much as legally you would have to go through inspections and re-certification. That's going to be a lot of effort.

 

If money wasn't a factor I'd get a semi motorhome conversion and pull with that, like a lot of race teams use to get to the track.

One of my old Suburbans the guy used to pull an 8600 lb boat, and it was a 1500 2wd with 5 lug wheels, IIRC it did have 3 inch rear brakes. The trailer I presume had brakes on it too. I pulled about 7500 lbs behind another Suburban once, a '57 Dodge full of parts on a car trailer, I had to stop for a light and it shoved me with all four wheels locked up about 10 feet.

The 93 GMC 3500 dually with the same trailer would stop and go like it wasn't even there. So I suppose if I needed to haul a lot with one of these vans my upgrade would be to that level of brakes.

 

I'm not sure how different the models/years are, but my 3500 EWB stopps on a dime with a load. I think you do better concentrating on brakes on the trailer, and making sure they are at their best.