mountainmanjoe

Mine isn't at the back. It's snugged up against the driver's side frame rail, starting behind the driver's seat, and going back to around the axle. I have no idea about pickups.
It might also have something to do with engine placement. I think van engines are offset towards the passenger to give the driver and pedals more room.
All will be revealed when you look at the drawings.

G3500 Toy Hauler

Yep, your gas tank is on the side like trucks. (I've been looking at the drawings. Page 55 for the 2018 year showed the Cutaway tank still after the rear axle, like my 2001.)

paul bell

I saw a school bus built on an Express cutaway chassis. Not new-but not too old, maybe 5-7 years old. Pretty common.

It was missing it’s center caps. The rear didn’t have the hub sticking out with the bolt in axles. It has the smaller 9-3/4" C-clip rear, not the 10-1/2" full floating rear.

This really surprised me.

I guess the only way to tell is looking at the rear hubs, not the options or weight class.

paul bell

I've determined that starting in about 2010, full size vans (Chevrolet Express and GMC Savana) stopped getting the full floating rear with 10-1/2 ring gears. They're all 14 bolt 9-1/2 inch rears with the axles riding on caged roller bearings inside the axle tube.

I'm not sure if the single wheel 4500 cutaway cab/chassis got a floater but all dual rear wheels did.

I've taken ownership of a 2006 3500 series SWB passenger van that has the big floating rear.

Interesting note: The Trailblazer SS and Saab 97x Aero with the 400 HP LS2 engine have a 9-1/2 inch 14 bolt rear.

Triaged

Isn't that the same time period when the HD trucks went to the 11.5" 14-bolt? Was it 2013'iah? Maybe AAM couldn't justify keeping production going for the 10.5" and GM had no choice? They made 6.6l Duramax vans up to 2015 right? Surely they didn't put a 9.5" behind those!

paul bell

You are correct it appears the diesel got the bigger rears.

I suppose its just the gas engine vans that lost the bigger rear ends. Prior to that, the MGVW would dictate which rear got optioned.