Whats you gas mileage on your squarebody truck?

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Camo

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Aye. Even my 305/700R4/3.08s couldn't pull down 20. I barely hit 17.5 on my longest highway trip.

Pretty realistic with a well tuned motor and your gearing and overdrive.
 

wildcatjason

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Welcome back Jason. Been awhile !!! :High 5:

I think sometimes people have inaccurate odo's and they read faster or more miles than actual.

I troll around a little bit. I am 1500 miles from my burb right now so it's kinda hard to update or work on it. I've read people thinking they can get this, but without detuning it and driving 50-55 I can't see it.
 

towjoe

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My 454 carburated V3500 wrecker gets about 5-6mpg, My 89 454 FI V3500 crewcab gets 7.5 mpg pulling trailer and 9mpg on hyway empty. my 86 C30 crewcab with 355 gets around 11-12mpg, My miltary M1028 with 6.2 gets about 16mpg, and best ever got was a 86 K10 4 speed 6.2 that got 21mpg. 10-12 pretty common with most square bodys small block trucks
 

HotRodPC

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85 K20 LWB
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454 - Turbo 400 - 3.73
Yo damn, and I thought our Medium Duty's getting 7-8mpg were bad.

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HotRodPC

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454 - Turbo 400 - 3.73
We've got 2 squarebody conventionals too but they are just our yard dogs for moving around and straightening up the lot. Not even registered for the street, let along DOT or DPS wrecker registered. They don't see pavement.
 

jake wells

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SM465 4:10 350 4bbl LS9 LT235/85/R16 tires it purrs at 55 WOT 75 mph
10ft flatbed and some gay hubcaps.

best i ever got on highway was 12.1 mpg going 45 mph
it gets 11 mpg going 55 mph and it get 9.5-10 mpg going 65 mph
i average 200-210 miles per 20 gallons of E5 gasoline.
 
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HotRodPC

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That's not real bad mpg for 4.56's and no OD, but do notice, you're going pretty slow. I drive 75-80 on interstates around here w/ 70mph limits. Actually more like 78 w/ Cruise Contol. I can get 13.2mpg at 65 mph with the the 84 C20, 3.21, Th400 and 454. But ****** 8.5 to 9 around town.
 

bucket

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SM465 4:56 350 4bbl LS9 LT235/85/R16 tires it purrs at 55 WOT 75 mph
10ft flatbed and some gay hubcaps.

best i ever got on highway was 12.1 mpg going 45 mph
it gets 11 mpg going 55 mph and it get 9.5-10 mpg going 65 mph
i average 200-210 miles per 20 gallons of E5 gasoline.

I like your stock hubcaps :shrug:

I don't remember if I posted it before, but my C10 loves 55mph. I got 19.7 out of it when I went down to see Curt awhile back. I've got about two months of gas receipts to figure my recent mileage from the daily commute. It's tuned just about perfect, I'm expecting about 17mpg. I'll bet I can top 20mpg on another road trip, but my problem is keeping it under 60mph.
 

crazy4offroad

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Was that truck 305 or 350? That's awesome mileage either way! Makes me wonder what a well tuned 283 could pull down in a SWB C10 (something really light). Isn't a 283 the CID equivalent of the modern 4.8 of today's trucks?I have a buddy who swears by the 283, had one in a LWB lifted 1/2 ton years ago and loved it.
 

bucket

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305, th350, and apparently 2.56 rear gears. It's a slug off the line. I've thought about a 283 but they are getting a little scarce. Also thought about a 327, which I really like. When the tranny finally pukes, a 700r4 and 3.42 rear will be going in and mileage should stay about the same.
 

jake wells

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305, th350, and apparently 2.56 rear gears. It's a slug off the line. I've thought about a 283 but they are getting a little scarce. Also thought about a 327, which I really like. When the tranny finally pukes, a 700r4 and 3.42 rear will be going in and mileage should stay about the same.

imagine if it had a little 250 instead with a turbo 400 then it would be beast :roflbow:
 

HotRodPC

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454 - Turbo 400 - 3.73
You mean a sled??? Thinking of hp loss with a Th400, you haven't got much left over out of a 250. Although, wouldn't need much with a 4.10 or 4.56 rear gear and OEM tires. But don't expect it to get out of it's own way.
 

towjoe

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Yo damn, and I thought our Medium Duty's getting 7-8mpg were bad.

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those are some sweet looking trucks. My meduim duty rollbacks get about 10mpg tho. ones a 5.9 cummins and other is a duramax both 2005. Shame your boss is letting the good trucks work in the yard where no one can see them.
 

HotRodPC

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454 - Turbo 400 - 3.73
I've heard the Duramax C6500's get good mpg but for some reason my boss likes the Cats, so he won't step up to a new C6500. It doesn't look it, but that Black C6500 is a 2000 model truck. The KW and Pete are 2005's. Then we've also got a 97 F350 Super Dooky also with smaller version of the Vulcan Strapless than what the KW has. Another local to company runs Duramaxs, man they are quiet and Comfy to drive. I wouldn't mince giving one a try.
 

towjoe

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I got a 454 vortex in a 2000 hd3500 that's a running sob. I wasn't to keen on a duramax at first, but I think if I have a choise from now on I'll try and buy duramax powered trucks. Anyone on here ever put a duramax in a square body????
 

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