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Gas Tank Size?

Discussion in '1973-1991 K5 Blazer | Truck | Suburban' started by smartpatrol, Feb 24, 2002.

  1. smartpatrol

    smartpatrol Registered Member

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    I have an 83 blazer with a stock 305 in it currently with a manual transmission. what is the best way to find out what size tank i have? 25 or 31 gallon. The fuel sending unit is bad :(

    I thought my Computer hobby was expensive......
     
  2. 4X4HIGH

    4X4HIGH 1 ton status Premium Member GMOTM Winner

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    If you look at the side of your blazer if the gas tank hangs about 6" below the frame it is a 31 gallon tank, the 25 gallon tanks were almost flush with the bottom of the frame. Almost all blazers had the optional 31 gallon tank in them. If you still have the sticker in your glove box it will tell you what tank is in it.

    1989 blazer, 383 stroker, 4.56 geared and detroit locked D44 front and 14BFF rear
     
  3. jekbrown

    jekbrown I am CK5 Premium Member GMOTM Winner Author

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    yeah, u can tell by how much it hangs down. Check out my webshots album...prolly a pic in there of how much a 31-gallon tank hangs down...compare it with yours and you are set.

    hope it helps,

    J


    See the on-going build up of my '85 Jimmy! <a target="_blank" href=http://community.webshots.com/user/jekbrown>http://community.webshots.com/user/jekbrown</a>
     
  4. 55Willy

    55Willy 3/4 ton status

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    the 25 gallon is 10.75" deep and the 31 is 12.75". if you have the skid plate on just look at the clearance, the 25 gallon will sit about 2.5" above the skidplate..this is due to the fact that CHEVY used the same skid for both tanks.



    <hr></blockquote>
    What do you mean, Where did I get it??...I <font color=blue>BUILT</font color=blue> the damn thing!!
     
  5. Chris Demartini

    Chris Demartini 1/2 ton status

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    <font color=blue>Anyone know the glove box codes for the different tank sizes?
     
  6. 4X4HIGH

    4X4HIGH 1 ton status Premium Member GMOTM Winner

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    Hey willy, I have seen several 25 gallon tanks and they did not have the same shield as the 31 gallon tank. They had a shorter shield to match the shorter tank.

    1989 blazer, 383 stroker, D44 / 14FF, 4.56, locked, 35 BFG mud
    Scott
     
  7. 55Willy

    55Willy 3/4 ton status

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    Thats GM for ya, I have a 77 blazer that had a 31 gallon with the same skid as the 78 burb that had the 25..



    <hr></blockquote>
    What do you mean, Where did I get it??...I <font color=blue>BUILT</font color=blue> the damn thing!!
     
  8. 4X4HIGH

    4X4HIGH 1 ton status Premium Member GMOTM Winner

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    Willy, how is that possible since the burb has a longer tank in it?

    1989 blazer, 383 stroker, D44 / 14FF, 4.56, locked, 35 BFG mud
    Scott
     
  9. 55Willy

    55Willy 3/4 ton status

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    it doesn't I pulled the skid plate off for Shannon and it bolted right on to my 77 blazer frame. Only the 40 gallon tank had a different rear crossmember to allow for the bigger tank.



    <hr></blockquote>
    What do you mean, Where did I get it??...I <font color=blue>BUILT</font color=blue> the damn thing!!
     
  10. JIM88K5

    JIM88K5 1/2 ton status

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    If you have a 31 gal tank, the RPO code is NK7.
    Jim

    88 Silverado K5 5.7-700R-208-10 bolts-4.56-35in
    Procomp AT's- some ORD stuff & a CV driveshaft
     
  11. 4X4HIGH

    4X4HIGH 1 ton status Premium Member GMOTM Winner

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    So the small burb tanks use the same skid plate as the 31 gallon blazer tank?

    1989 blazer, 383 stroker, D44 / 14FF, 4.56, locked, 35 BFG mud
    Scott
     
  12. JIM88K5

    JIM88K5 1/2 ton status

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    Parts catalog says same skid plate for sub &amp; blazer exc
    for 40 gal tank.
    Jim

    88 Silverado K5 5.7-700R-208-10 bolts-4.56-35in
    Procomp AT's- some ORD stuff & a CV driveshaft
     
  13. 55Willy

    55Willy 3/4 ton status

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    yes.



    <hr></blockquote>
    What do you mean, Where did I get it??...I <font color=blue>BUILT</font color=blue> the damn thing!!
     
  14. Greenblazer-AZ

    Greenblazer-AZ 1/2 ton status

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    If the tank is almost empty, go fill it up and look at the gas pump if it held more than 25 gallons you must have a 31 gallon tank. What's the most amount of money you've put in the tank divided by the aproximate price per gallon. If you know how much money it takes to fill when almost empty you can tell how many gallons it holds. The first time I filled mine up it held almost 29 gallons so I know I don't have a 25 gallon tank.

    If you knew the truth, you too would be against marijuana prohibition!
    Blue '74Blazer Topless W/ 35 BFG Muds1" Body Lift W/ Energy Susp. Bushings
     
  15. smartpatrol

    smartpatrol Registered Member

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    Thanks alot guys! I would do the fill up test....if my fuel sending unit worked. I will check the glove box.

    I thought my Computer hobby was expensive......
     

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