Frame differences between a 3500 Pickup and Chassis Cap

[Hendrickson360]

Hello!

 

since i cannot find info on this like its possible with Dodge and Ford, maybe someone here can help.

 

So with the older model lines, there was a big difference between the Pickup Frame and the Chassis cap frame.

 

The Pickups was fully boxed from 2011 on and hat a profile of around 8.4x3.4x0.18“ made out of 60k PSI steele, which was far ahead oft he competition at the time.

Did this change in any way?

 

The Chassis Cap apparently had a gigantic profile of 11x2.5x0.5!!! Now this one was obviously an open C, however i dont know if the entire frame was open c, like it is with the modern day 4-6500, or it was a mix of boxed front from the pickup version with an open C rear end, like Ford und Dodge are doing on their chassis caps. I also dont know i fit was a layered frame, but i’m pretty sure it was. PSI rating was only 36k.

 

Did this change in any way?

 

Kind regards

 

Marcus

[64BAwagon]

Youre question is probably beyond the depth of what anyone other than a GM employee with access to the system can provide. Youre getting deep into engineering questions. Unless you pursued it through an upfitter program manual but even then there have been some rolling changes through the years. 

All I can say is that the chassis cab frames do vary quite a bit from the pickups, especially in length and crossmember configurations (fuel tank(s) )

[redwngr]

First, they are chassis cab, not chassis cap. (as in cab and chassis)

 

GM has all new HD pickup frames for 2020 model year onward.

Previous HD frame change was the 2011 model year. 

 

GM makes frame information available for upfitters that buy both pickup and chassis cabs (of varying frame length).

Not sure if the upfitter info is what you are looking for, but there are many pages to wade thru. 

There should be load rating information there.

 

 

 

Edited June 14, 2023 by redwngr

[newdude]

5 hours ago, Hendrickson360 said:

Hello!

 

since i cannot find info on this like its possible with Dodge and Ford, maybe someone here can help.

 

So with the older model lines, there was a big difference between the Pickup Frame and the Chassis cap frame.

 

The Pickups was fully boxed from 2011 on and hat a profile of around 8.4x3.4x0.18“ made out of 60k PSI steele, which was far ahead oft he competition at the time.

Did this change in any way?

 

The Chassis Cap apparently had a gigantic profile of 11x2.5x0.5!!! Now this one was obviously an open C, however i dont know if the entire frame was open c, like it is with the modern day 4-6500, or it was a mix of boxed front from the pickup version with an open C rear end, like Ford und Dodge are doing on their chassis caps. I also dont know i fit was a layered frame, but i’m pretty sure it was. PSI rating was only 36k.

 

Did this change in any way?

 

Kind regards

 

Marcus

 

 

A pickup frame is different from the Chassis Cab frame, yes.  

 

If you went in and ordered a WT or LT Dually with a box delete, its going to have the regular boxed frame that they use.

 

If you ordered a WT or LT Chassis Cab, its going to have the c channel big rails from about the cab back to past the rear axle.  The straight "upfitter" style frame with   Front end to about under the driver's seat is boxed frame from the pickup frame.  

 

Here is the specs for the 3500 pickups - https://www.gmfleetorderguide.com/NASApp/domestic/printbook?pdftype=option&lang=1&vehicle=22467&rpoid=36178

 

Can't find the chassis cab one but its going to be different past the cab for sure.  I think the frame also has the industry standard NTEA 34 inches rail to rail spacing.  

[Hendrickson360]

Hello,

 

thank you very much for this document (and thx to the rest to for the info!)

 

So interestingly enough, both the dimensions and steel quality did not change since 2022, but well, it was best in class since then. The 2017+ Ford Frame has even more height (or depth by those documents) but "only" 50k PSI steel, so similiar nowadays.

 

What i wonder: Since the C-channel frame of the Chassis cab is so much larger (or used to be) how are they put together? And are they still of diffeent steel quality? Seems kinda weird. Ford upped they steel with the Cchassis Caps to 50.000k too, but the dimensions are much smaller.

 

Or maybe the boxed front end of the GM is also different from the first half of a pickup frame in the first place...

[Hendrickson360]

Hello,

 

Since there is no data for the 3500 chassis caps, maybe there is something for the 4500 one? I guess the frame would be the same for 4-6500?

 

Kind regards

 

Marcus

[newdude]

8 hours ago, Hendrickson360 said:

Hello,

 

Since there is no data for the 3500 chassis caps, maybe there is something for the 4500 one? I guess the frame would be the same for 4-6500?

 

Kind regards

 

Marcus

 

 

4500-6500 Silverado are a completely different truck/frame.  They are joint venture built and designed with International Navistar.  I/N builds the frames and does all the chassis work, GM supplies the cabs which are old K2XX cabs and interiors, the headlights (from 14-15 1500 Silverado) and they did the design work for the hood.  GM/DMAX does the L5D Duramax for it, Allison supplies transmissions.  Built a lot like the old 03-09 Topkick/Kodiak trucks.  

 

Here's a snapshot of the 4500-6500 frame specs from the GM Upfitter body builder chassis manual: CV_BB.book (gmupfitter.com)

 

 

 

 

 

 

[Hendrickson360]

Hello and thank you again! What is really weird: I checked an old Terrastar-Doc of mine and apparently the frame was pretty much the same, but they did for some reason a downgrade in terms of PSI rating!

 

Now of course i would be really curious about that chassis cap frame, if it kinda sits between them and how the boxed front end and open c rear are connectet...