Towing concerns...Avalanche comparison FRAME 2500

Are the Avalanche Frames the same channel design that Chevy ues on all thier 3/4 ton and  1 ton trucks?  Specifically - at the rear of the trucks....the frame rails are not boxed..but simply an open channel design...

No the 2500 AV are on the suburban platform, not the Silverado platform.

Thanks fr the responce

How do the frames differ?

The silverado is wider  for one thing.

But do not think a AV is on a Silverado frame I ordered some suspension parts thinking they fit, they did not. They are very different. The AV is a Suburban the Silverado is a pickup truck.

Sent ya a link

thanks for the link...I'll check it out !

I actually took a few pics of a 2500HD and a 3500 frame. I will try to post later.......when you see it you'll understand why I'm returning my putnam and getting a Reese Titan hitch.

Excellent Rocket !   

I'll wait !..

MichiganSilver03 said:

The silverado is wider  for one thing.

But do not think a AV is on a Silverado frame I ordered some suspension parts thinking they fit, they did not. They are very different. The AV is a Suburban the Silverado is a pickup truck.

Sent ya a link

Click to expand...

That also reflects in the tow ratings...

With absolute certainty, the Avalanche is based on the Suburban frame.

1500 AV frames correspond with 1500 Subs/YukonXLs/Escalade ESVs

2500 AV frames correspond with 2500 Subs/YukonXLs

The difference between AV/Sub/YXL 2500 frames, versus 2500 truck (and 2500HD truck) frames are several and varied. 

These differences include, but are not limited to:

Resistance to Bending Moments (RBM)
Web Section Height
Flange Width
Material Thickness (and this is key as to why 2500 AV frames distort locally, especially with aftermarket hitches like the Putnam)
Shape
Hole Locations
Leaf Spring hangar mounting position
Rearmost Crossmember style/shape
Rearmost Crossmember attachment
Overhang aft of Rear spring hangar

Pretty much everything about the rear and middle sections of the 2500 AV/Sub/YXL frame differs from that of a 2500HD truck.

The 2500LD (or 1500HD) truck is a closer match as far as material thickness and type of factory hitch issued (non gusseted), but otherwise differ in the above respects as well.

Where you will find some similarities between certian 2500 4x4 trucks and 2500 AVs and Subs is in the very front end of the truck.

GMT800 frames were designed in three major sections to produce around 50 different vehicles on the platform.  There is

a. The REAR section we've been discussing, because it relates to the reason for the question (towing).
b. The Center section, that is entirely dependent on the body style, wheelbase, and GVWR.  And, there is
c. The FRONT section, which can be more common than the other sections among the 50 types of GMT800 vehicles.

The front section among 2500LD 4x4s is common to 2500 Utilities among those similarly suspended (ie, if 4x4 with torsion bars, the same front section will be found among 2500 AVs, Subs, YXLs, as well as the Hummer H2, with some modifications, like the front most crossmember, some frame holes, etc.

The front section to the 2500HD and 3500 are common to each other, and look very very similar to the front sections in the other 2500s, there are some differences in material thickness, hole locations, bracketery weldments.  Differences are more substantial in 2WD trucks.  There is even a thickness difference between a 2WD 3500HD, and a 2WD 3600 (code name for Chassis Cab).  And of course the rear frames between those trucks are waaay different.

By the way, old school GMT400 frames were a lot thicker than GMT800 frames.  A GMT400 Suburban can have, in some sections, thicker material than a GMT800 2500HD truck.  Like twice as thick in some places.

The trick with the newer trucks, and the Magna frame system, was to make it lighter while still maintaining or increasing resistance to bending.

But the frames are definately not the same.

That's also why there is no diesels or Allison tranny AV either

Except for one.

OK here is a pic of a 2500 HD frame. Looks to be almost  twice as tall as our frames.......