1985 F-150 dual gas tank size
Side mount tanks on a long box (8ft box) are 19 gallons they are 16 gallons for short box (6ft box), the rear mount tank is 19 gallons, there was also a Extra large tank as a option (rear mount) which is 38 gallons. All this is for a 85 F-150. But if a old owner changed the tank it might be a diiferent size, there is a 16 gallon tank for the short bed trucks and a 18 gallon tank (90 and up, but i think that it will fit your truck) There is also a 25 gallon tank option for the rear mount. best of luck.
How big are the two gas tanks on a 1988 F150? Has a 300 6cyl. 4 speed with over drive.
they are ruffly 17/17 gal. ford would never put dual odd sized tanks on their trucks. just to let you know "side mount tanks" are also called saddle tanks (gm). fords are all frame mounted tanks (mounted in the frame)the best way to find out is when both are on half, fill'um up.
Ford MOST CERTAINLY put "odd sized" tanks on their trucks, at least in any of the 1980-86 style F150s that I have owned. Just to let the previous responder know. My 1985 F150 Explorer XL had a rear 19 gal and a front 15.5 gal tank. Straight from the manual. Also, with those style trucks there are usually THREE total fuel pumps -- one in each tank and a main pump further up the frame.
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