Fuel tank to driveshaft clearance

justjeepin86

justjeepin86

Well-Known Member
Joined
Jul 9, 2005
Location
Winston-Salem, NC
I'm working on a 71 k20 restoration. Fuel tank options are limited and don't fit the bill, so i want to fab one up. Problem is there isn't a lot of real estate to work with inside the frame rails. I built one from cardboard the size i want, but it's about 1 1/2" from the driveshaft. I would be willing to remove 1 more inch from the width of the tank if necessary for 2 1/2" of clearance. I'm aware that the frame can twist a fair amount on these old trucks. What say ye nc? Will that be enough to not hit?
 

Attachments

  • 20210130_165350.jpg
    20210130_165350.jpg
    182.2 KB · Views: 170
  • 20210130_165411.jpg
    20210130_165411.jpg
    109.8 KB · Views: 169
Not enough for me, maybe fine for you.

Just remember if it makes contact you are going to have metal on metal (ie spark) and a big container of gasoline that you are strapped to.
 
I'd run it at 2" and rock on. Even if it does rub, it's not gonna suddenly shear through and explode. Put a skid on the side of it if it makes you feel better.
 
paradisePWoffrd said:
Can you not put it behind the rear axle, like the blazer?
Click to expand...
Typically on the 67-73s if you want it out of the cab it is either in the bed or behind the axle from what I’ve seen
But then you are filling through the bed floor
 
Ron said:
Typically on the 67-73s if you want it out of the cab it is either in the bed or behind the axle from what I’ve seen
But then you are filling through the bed floor
Click to expand...
Agreed. With a 4wd, you could possibly put the filler behind the plate, or behind the taillight if it's a fleetside.
 
I feel like cardboard isn't the most ideal material to build a tank from, but I'm in for the tech info to see how well it works :D
 
jeepinmatt said:
I'd run it at 2" and rock on. Even if it does rub, it's not gonna suddenly shear through and explode. Put a skid on the side of it if it makes you feel better.
Click to expand...
Honestly, being close may keep the damage minimal of you lose a shaft. I may try to wrangle some driveshaft loops too. But, you are right. I'll probably run a second layer of aluminum on that's side and the bottom.
 
Croatan_Kid said:
I feel like cardboard isn't the most ideal material to build a tank from, but I'm in for the tech info to see how well it works :D
Click to expand...
Funny, that's what my wife said. I told her i was going to paint it and that should take care of it
XJsavage said:
Post pics of the truck when you're done.
Click to expand...
I plan on starting a build thread at some point. I've got tons of pics, but it will be a long road.
 
justjeepin86 said:
Honestly, being close may keep the damage minimal of you lose a shaft. I may try to wrangle some driveshaft loops too. But, you are right. I'll probably run a second layer of aluminum on that's side and the bottom.
Click to expand...
For some reason I assumed it would be steel. I'd put an 1/8" steel skid on that side, spaced out about 1/4" from the tank if possible. Steel on steel will hold up surprisingly well. Steel on aluminum, the aluminum turns into butter.
 
jeepinmatt said:
For some reason I assumed it would be steel. I'd put an 1/8" steel skid on that side, spaced out about 1/4" from the tank if possible. Steel on steel will hold up surprisingly well. Steel on aluminum, the aluminum turns into butter.
Click to expand...
Agreed. If you can bead roll/corrugate the steel to make it stronger, it'd be better. Or weld some thin ribs down the back of the skid.
 
The tank I put in my HD is plastic and pretty close to the driveshaft. Tank is 7 feet long and my shaft is 62" and 5" diameter....not that I'm bragging :D I'm not real worried about it. I think there's maybe 2 or 3 inches between the two.

In short...I wouldn't worry about it, BUT, if you're making it....might as well put some kinda scatter shield on it.
 
I would be good with the gap you have. Wouldn't bother me.
 
It looks like it might be too narrow between the frame rails to fit, but in case it isn't.... an S10 Blazer from the mid/late 90s has a fuel tank that's about 14" wide and 5ft long. They hold about 20 gallons. I believe they're all steel... but there may be some poly ones out there as well.
 
shawn said:
It looks like it might be too narrow between the frame rails to fit, but in case it isn't.... an S10 Blazer from the mid/late 90s has a fuel tank that's about 14" wide and 5ft long. They hold about 20 gallons. I believe they're all steel... but there may be some poly ones out there as well.
Click to expand...
Yeah, my mockup is 10" wide. I think I will end up around 9" and extend the length 2-3". Will land me 24-25 gal.
 
Back
Top