1500 vs 2500 frames

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bobsburban

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Just a question about the difference between the actual frame design/materials/construction between a 1500 and a 2500 Suburban... Curious mostly as I think my 2011 "gentle offroad" upgrade is coming along well and I'm only towing 4500 lbs give or take with our 17' Winnebago TT but should I ever get the itch to go larger, a 2500 is a reasonable upgrade. They are getting scarce, though, so I was wondering about the wisdom (and economic sanity) of just dropping the 3/4 ton axles, springs, etc. and a 6.0 into my 1500. If the frames are essentially the same, then it might make some sense. If the 1500 frame is wimpy in comparison to the 2500 frame, sourcing a good 2500 and upgrading/rebuilding it as needed might be a wiser course of action.

As I said, just curious at this point...

Thanks in advance,

Bob
 

avalonandl

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The 2500 frames are very stout. Much deeper and heavier. They are set up for leaf springs in the rear. I suggest finding one to look at first. I don’t think you can just bolt the axles on.
 

swathdiver

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Just a question about the difference between the actual frame design/materials/construction between a 1500 and a 2500 Suburban... Curious mostly as I think my 2011 "gentle offroad" upgrade is coming along well and I'm only towing 4500 lbs give or take with our 17' Winnebago TT but should I ever get the itch to go larger, a 2500 is a reasonable upgrade. They are getting scarce, though, so I was wondering about the wisdom (and economic sanity) of just dropping the 3/4 ton axles, springs, etc. and a 6.0 into my 1500. If the frames are essentially the same, then it might make some sense. If the 1500 frame is wimpy in comparison to the 2500 frame, sourcing a good 2500 and upgrading/rebuilding it as needed might be a wiser course of action.

As I said, just curious at this point...

Thanks in advance,

Bob

GMT900 2500 frame is like that of the pickups pre-2011. They are way different than the 1500. They have 10.5" rear axle and use torsion bar front suspension and leaf springs out back. So none of that is compatible. There are quite a few for sale on AutoList and such right now, meaning about six GMCs and about double for Chevys! The 1500 frame is basically like the heavy-half frame of the previous generation, stronger still.

Curiously, the 2500s use a 26 gallon main tank and an 11.5 gallon aux tank above the spare tire and it fills and gets used up seamlessly, most people don't even know they have a second tank, there's no provision for switching tanks, it's all done by the computer. That tank is too tall to fit above a 1500s spare without removing said spare.
 

intheburbs

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The GMT900 1500 and 2500 share the same body. This leads a lot of people to draw the (mistaken) conclusion that the 2500 is simply a "beefed up" 1500.

Beneath the body, however, are two completely different trucks. Frame, suspension, axles, brakes, engine, transmission - all completely different.

OP is right that the 2500s are getting scarce, and pricey. If you want one in good shape, 100k(ish) miles, you'll be paying $20k or more. I'm actually terrified of the thought of having to replace mine, if the time ever comes, or if I get into a wreck.
 
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