I've been shoping out a new gas tank for an 88 suburban(Blazer is the same so I'm told)... basically, the 31 gallon for a TBI application.

However, I'm getting a bunch of odd information.

I've seen a tank listed as 82-91 for it.

I've seen it split up as 82-86 and 87-91.

And I've seen one listed as 73 to 81.

My goal is to get a nice 31 gallon TBI "ready" tank for my current project. I had a misshap with the previous tank so I'm shooting for a new one.

So I'm curious, aside from the sending unit, what is the difference between all those tanks(73 to 81, 82-86, and 87-91)?

Can the 73 to 81 be made to work with the TBI sending unit with no issue? The picture I saw of it, made it look exactly like the one I am replacing. The only question in my mind is whether the sending unit would fit.

Fuel injection on the chevys started in 87 so my guess would be a tank from 87-91. 92 was the new body style.

Also keep in mind there are 26 or 31 gallon tanks for the fuel injected Blazers. Before that, according to this link it was @ 24 and 31 gallons.
Travis

http://coloradok5.com/specs.shtml

I just put a TBI fuel pickup/sending unit in my 31 gal '73 K5 tank. Fit just fine and works well. No problem with the fuel gauge either. I got it from the wrecking yard, so not sure of the year. I found a high pressure in-tank pump that fit and would work with my EFI. Got it from AC Delco. I don't know the differences in the various year tanks though. Sorry.

KWTMECH,
That was my understanding also... but then I got to ebay and they listed the tanks both ways. Plus, they list the 73-82 version... that was about $30 cheaper.

MOGXJ44,
I wasn't aware of the 25 gallon... but I've been looking on ebay for the 31 gallon strictly. LOL, my gas hog will need every gallon :P

I just put a TBI fuel pickup/sending unit in my 31 gal '73 K5 tank. Fit just fine and works well. No problem with the fuel gauge either. I got it from the wrecking yard, so not sure of the year. I found a high pressure in-tank pump that fit and would work with my EFI. Got it from AC Delco. I don't know the differences in the various year tanks though. Sorry.

So you just dropped the whole unit into the 73 and it screwed in fine?

THAT is just the news I was hoping for ;)

If you're running EFI, do not get cheap and buy the early model tank! The EFI requires a baffle and "sump" for lack of a better description, to prevent the pump from starving for fuel. These pumps run at high RPM, and use the fuel as a coolant. A little trick to make your pump last a little longer, don't let your tank run below a quarter, as the pump will be up out of the fuel it uses for cooling( the sock will still be submerged). Hope this helps.
Jimbo

If you're running EFI, do not get cheap and buy the early model tank! The EFI requires a baffle and "sump" for lack of a better description, to prevent the pump from starving for fuel.

Is that the big difference between the early and late model tanks?

Yes, it is. My 86 tank had no baffles. I bought a tank for a 87-91 blazer and it has an internal sump/baffle system (off ebay). There is no difference in the tanks other than that.