Whats you gas mileage on your squarebody truck?

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tophat36

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Has anyone ever done a propane swap? A coworker mentioned they had done that before. Does that improve efficiency at all…also I know nothing about anything to do with this stuff, so if this is a stupid question please don’t berate me lol.
 

TotalyHucked

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I don't remember if I've posted in here but I get 13-17mpg around town depending on how rowdy I'm feeling lol. Hwy ain't too bad, 18-22mpg from 70-80mph and 14mpg at 90+ lol
 

SirRobyn0

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Has anyone ever done a propane swap? A coworker mentioned they had done that before. Does that improve efficiency at all…also I know nothing about anything to do with this stuff, so if this is a stupid question please don’t berate me lol.
I won't berate you. At one time I worked at a shop that sold propane and I looked into it some. Your mileage will go down, by about 1/3.

This is off the department of energy website "Because a gallon of propane has 27% less energy than a gallon of gasoline, the fuel economy of propane vehicles is slightly lower". So you'd need to pay less for propane than gasoline, and it needs to be quite a bit less. If your a large fleet company and you have large bulk loads of propane delivered I can see how it could be viable. I think that's why it's not a very common conversion at all.
 

tophat36

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I don't remember if I've posted in here but I get 13-17mpg around town depending on how rowdy I'm feeling lol. Hwy ain't too bad, 18-22mpg from 70-80mph and 14mpg at 90+ lol
What’s your setup to get such a higher range than what seems to be typical?
 

HotWheelsBurban

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I won't berate you. At one time I worked at a shop that sold propane and I looked into it some. Your mileage will go down, by about 1/3.

This is off the department of energy website "Because a gallon of propane has 27% less energy than a gallon of gasoline, the fuel economy of propane vehicles is slightly lower". So you'd need to pay less for propane than gasoline, and it needs to be quite a bit less. If your a large fleet company and you have large bulk loads of propane delivered I can see how it could be viable. I think that's why it's not a very common conversion at all.
It's more common in Europe and the UK than here. Their propane is more expensive than ours is, but still much cheaper than petrol.
 

TotalyHucked

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What’s your setup to get such a higher range than what seems to be typical?
LS and overdrive lol. 5.3 with ~10.5:1 compression, 799 heads/TBSS intake, BTR stage 4 V2 truck cam, 4L65E with a 3200 stall and 3.90 gears
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tophat36

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LS and overdrive lol. 5.3 with ~10.5:1 compression, 799 heads/TBSS intake, BTR stage 4 V2 truck cam, 4L65E with a 3200 stall and 3.90 gears
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Lol don’t know what any of that means but good to know you are able to get numbers that high!
 

Bextreme04

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Lol don’t know what any of that means but good to know you are able to get numbers that high!
He swapped it to a hopped up modern fuel injected LS motor and matching electronically controlled overdrive transmission from a 2001-up GM vehicle
 

TotalyHucked

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Lol don’t know what any of that means but good to know you are able to get numbers that high!
Haha This is a hopped up engine and transmission from an '06 GMC Envoy Denali, so it has fuel injection and all the modern goodies to make it drive nice and get good mileage with alot of power
 

tophat36

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Haha This is a hopped up engine and transmission from an '06 GMC Envoy Denali, so it has fuel injection and all the modern goodies to make it drive nice and get good mileage with alot of power
I guess I don’t understand the point of all that, if you want a modern truck why not just buy a new/newer one? I guess it depends on your goals and what you want to use it for. I like the idea or preserving something in time but that’s probably an unpopular mentality.
 

TotalyHucked

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I guess I don’t understand the point of all that, if you want a modern truck why not just buy a new/newer one? I guess it depends on your goals and what you want to use it for. I like the idea or preserving something in time but that’s probably an unpopular mentality.
Cuz I like the styling of these trucks, I've loved them since I was a kid. But weezy old small blocks and carbs suck lol. Plus this one had a hurt 305 in it and me and my buddies roadtrip all over the US in these things. I wanted the best of both worlds, classic looks but modern performance. Some day I'd like to add a mostly original truck to the stable and keep it that way cuz the nostalgia is cool, I will admit.
 

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^^^^^Ditto. Love the looks but hate the crappy power, brakes, AC, radio, gauges, transmission.... RetroMod and have something that looks good AND something you can spend more time driving than working on. To be fair you have to compare apples to apples. I now have all that fancy modern stuff in my 85K20 but I only get around 15 mpg/highway but my truck probably weighs twice what Hucks does.
 

Grit dog

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Has anyone ever done a propane swap? A coworker mentioned they had done that before. Does that improve efficiency at all…also I know nothing about anything to do with this stuff, so if this is a stupid question please don’t berate me lol.
Nope but I saw a propane fired 70s model, with a turbo!! For sale a couple years back. The conversion and turbo were very old. Looked like a pkg deal aftermarket setup. Very unique.
 

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