4.10 would be the preferred ratio for heavy towing.

I have a Suburban with the 6.0 and 6L90.  Great combination, and pretty fucking bulletproof.  A buddy had a Savanah with the same combo with 750k on the odo and still going.  It was on its second engine and the trans had been rebuilt once.

I had a Ford van about 7 years ago. 12 passenger e350, it towed just fine I would regularly haul 5-6k lbs of flooring in a small trailer. Imo i enjoy driving work vans more than trucks, I love the visibility and seating position vs a long hood on a truck.

I really miss the little trailer I had for it too, 5x8 with double 7k axles. You couldn’t  overload that little thing, I’ve never seen another one that size with double axles

You could change the gears and then have the cpu remapped or change the chip to correct speed and shift points.

I’ve got a lot miles in the seats of work vans. Driving empty the GM vans are alright. Hauling heavy the Ford has superior weight handling and breaks. The GMs have mushy suspension and brakes.

The gear ratio probably doesn’t matter, it’s got a 6 speed with smaller tires and wheels than the pickups get.

GM vans are seriously old school. After 30 years on the same chassis, they drive like boats, still have too many issues- mostly electrical, that GM fails to correct. The windows and headlights rattle down the road. Brake pedal hits the floor without warning, where’s the brake pad squealers GM?

After doing a lot of research, I bought a Nissan van. It handles much better, brakes better, handles weight just fine, has more front seat space and comfort. The 5.6 will smoke the 6.0. It’s basically what GM should’ve updated to a long time ago.

I’ve got about 10 Chevy 2500 express vans with service bodies.  

They are slow and take some fuel.

Even new they have quirks.  They drive like a boat.  Like a 50s Buick.

They will handle up to 9-10k then they start acting funny over that.  

They are slow and are old, but they just work.

The driving position is relatively cramped.  

That said, they are great reliable units.  I am switching to all transit vans because I don’t tow with mine they are service trucks.

They also can’t seem to hold alignments