GMT400 tank swap

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Chevy454z71

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Has anyone installed the 25 or 34 gallon fuel tank from a gmt400 truck in place of a stock 20 gallon tank?
 

CheemsK1500

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I've never seen this done, but I have seem a few people install a 40 gallon square body Suburban tank onto a square body pickup. This would probably be easier to to do since the distance between frame rails of square pickup is closer to a square Suburban than it is a GMT400 pickup.

It's also worth noting that squareboy pickup tanks are located on the outside of the frame rails, and Suburban tanks are located on the inside. If you're good at fuel line plumbing, you can actually run 3 separate tanks on one truck.
 

CalSgt

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Looking at one I thought the big hump on the top of the GMT400 tank would prevent the swap from looking decent.
 

tnvarmint

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Not sure but I have been doing some research for swapping either a Blazer or Suburban tank. Lots of videos on YouTube showing it and seems to be fairly simple. Think the Blazer tanks are 26g and Suburban tanks are 40g from what I have seen. Just search "GM square body side saddle to rear frame tank swap"
 

Hunter79764

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Suburban tanks were different sizes, I think a 26 gal, 32 gallon, and 40 gallon IIRC, each one has a different sender. I've got the 26 in mine, unfortunately, but replacements are available for all sizes.
 

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