ken56 wrote:
The 7100 lb. is gross vehicle weight rating, not tow rating.
Actually, looking at the Chevrolet website the 4.3L V6 has a GVWR of 7100# and a tow rating of 7100# with the 12000 GCVWR.
I actually think the V6 would tow a 4000# (wet) trailer pretty well. We towed a 5000# GVWR HTT with an 05 Suburban with the 5.3L and 3.42 axle and I didn't find myself ever wanting more power from the truck. My Suburban would have had 10 more HP and 30 more #-ft of torque as compared to the new 4.3L V6, but the V6 is also coupled with the 6 speed transmission. At a minimum you would have 4 usable towing gears while I had 3 in the Suburban.
I don't think you can go wrong with either engine. The 4.3L should get the job done and return some pretty good gas mileage while the 5.3L should do the job effortlessly
