Can't believe this gas mileage

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Ron Sebastian

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Just started to keep track of mileage, I thought it was my imagination as the gauge was not moving, after driving 152 miles, now it's at 1/2 tank (left side saddle tank). I'm getting over 19 miles per gallon driving around town. Will prove tomorrow when I get gas to see if I'm really at half a tank. Saddle tanks are 16 gallons each, right? Can't believe fixing the intake manifold leak would equal better gas mileage.
 

eskimomann209

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Just started to keep track of mileage, I thought it was my imagination as the gauge was not moving, after driving 152 miles, now it's at 1/2 tank (left side saddle tank). I'm getting over 19 miles per gallon driving around town. Will prove tomorrow when I get gas to see if I'm really at half a tank. Saddle tanks are 16 gallons each, right? Can't believe fixing the intake manifold leak would equal better gas mileage.
If you have a long bed it can be a 20 gallon tank
 

Dmack

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Hope is a good thing, but I would be surprised at those numbers. Never trust the gauge. You need to fill the tank, drive for a while, top the tank back off, then divide the miles traveled by gallons used.
 

AuroraGirl

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I thought longbed was 18, at least I recall when I purchased mine. The saddle tank that I got for half off because it was returned to amazon with a small dent in the crimping around the corner near the level sender. That was a good deal.
 

ali_c20

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I have a long bed c20 (74) with 2 20ies and I wouldn't get that mileage even if i would calculate it with double 12 gallon tanks :)
 
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HotRodPC

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I have seen long beds with 16 gallons also. Shortbeds will always be 16, but there are at least a few longbeds with 16. Just don't be upset when you finalize your test and it's not 19. Be thrilled if it's 15 or better. Most of us are getting 10-13 in 4x4's but you do have TBI right? That'll help get it up a bit.
 

Ron Sebastian

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Not quite what I thought but still pretty good. The truck has 16 gal tanks just to assure everyone. Drove 172.5 miles, gauge read just under half a tank see pic. Fueled up and pump read 9.928 gallons, so I'm thinking gauge is pretty accurate. 17.375 MPG is what I come up with.
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GXPWeasel

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That's better than I can get with my '15 Silverado this time of year!
during the summer months, sure..

However, I do suffer from a good sounding exhaust, and 2 daughters who are constantly asking me to drive faster. :waytogo:
 

gotyourgoat

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Not quite what I thought but still pretty good. The truck has 16 gal tanks just to assure everyone. Drove 172.5 miles, gauge read just under half a tank see pic. Fueled up and pump read 9.928 gallons, so I'm thinking gauge is pretty accurate. 17.375 MPG is what I come up with.
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Haha, welcome to food bag.
:D
 

Ron Sebastian

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Stay with me, I'm not a math major. 16 gallon tank, each quarter is 4 gallons. Half a tank 8 gallons. Just past half give or take the width of the Needle, I'm good with almost 10 gallons.
 

eskimomann209

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Except the 4 gallon mark is each quarter so to get 10 gallons in the tank you need to be closer to the 1/4 mark. I drive mine daily to get 10 gallons in, I’m closer to the 1/4. To get 13 gallons in, I’m scary close to the empty mark.
 

Overland Suburban

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Sweet! I had a 1974 4x4 with a 350. I got 17 mpg with it tuned up. Now I'm trying to figure out how I'm going to get a Suburban to get some mileage. Going to build a mild tuned up 350 first. Than going to go about building a 383 stroker. My guess is torque will win out in the economy department with a vehicle that heavy.

Some people might ask why would you build TWO engines. Because this **** is ******* fun and I can! :cheers:
 

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