Whats you gas mileage on your squarebody truck?

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HotRodPC

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We had a member mention thinking about it at one time, but usually the hot topic on Diesel here, is to go Cummins. We do have a member here with a Burb that has a 4BT Cummins and another 1 ton that has a 6BT.
 

wildcatjason

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My 2003 dodge 24 valve cummins gets 16 in town 20 on the highway. If you ever thought about a common rail.
 

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my 87 with 4.3 t400 3:08 rear gets about 17 per gal. no matter how i drive it usually the pedal gets stuck to the floor
 

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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????

I looked into for my '84 K2500, but they're too friggen expensive. And I'm thinkin the Allison would be hard to squeeze in. It'd be awesome though.
 

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I looked into for my '84 K2500, but they're too friggen expensive. And I'm thinkin the Allison would be hard to squeeze in. It'd be awesome though.

Most diesel swaps that will actually tow will take some mods to the firewall and tranny tunnel to make work. I had to cut part of the firewall and raise the tranny hump to get my zf5 to fit. These trannies are tall or wide or both.
 

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My brother has a 88 V3500 with a 24 valve cummins in it and the 12 valve pump. He put the nv4500 in it and the dana 80 rear. He gets 16 mpg hauling our offroad buggys on a 30' gooseneck on the highway. Made one sweet ride. I've heard of some people putting the 4bt in the m1009 blazers and getting 24-25 mpg. I think that would make a nice daily commuter.
 

HotRodPC

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Wildcatjason has a 4BT in his 2wd Burb. I forget what he said he got, and still working on it, but I know it was 20 or better.
 

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87 305 tbi stock +open breather&msd 6a /rebuilt stage 2 700r4. stalls when timing advanced is pluged in...wtf. Anyway 19/20 mpg unpluged. But surges at idle
 

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Wildcatjason has a 4BT in his 2wd Burb. I forget what he said he got, and still working on it, but I know it was 20 or better.

It would average 20 in the city before I turned up the pump. It's sitting back home now so I haven't had a chance to calculate highway mileage. It also had the stock turbo on it at the time and the steel front end. I doubt it's changed much with the mods I made. Diesels usually don't unless you go heavy on the fuel and dont do anything with the air. Its lighter now and my next plan is still to chop the back and turn it into a four door step side. Its went though 5/8 of a tank on that okc trip you saw me on.
 

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I would under the impression that a duramax swap might losing the heat box as well. It looks like a wide ass engine. I don't know that for a fact but it appears wider then the 6.5. But I would hate to replace the environmental system. The swap itself would probably run 10 grand and all the extras with it. I test drove a mileage candidate that was 20000. That was with 149000. There is just a lot more options for trannys with cummins I would still like to have a common rail 4bt or an "isb170" over the ve pump I currently have. I love my 24 valve.
 

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I would under the impression that a duramax swap might losing the heat box as well. It looks like a wide ass engine. I don't know that for a fact but it appears wider then the 6.5. But I would hate to replace the environmental system. The swap itself would probably run 10 grand and all the extras with it. I test drove a mileage candidate that was 20000. That was with 149000. There is just a lot more options for trannys with cummins I would still like to have a common rail 4bt or an "isb170" over the ve pump I currently have. I love my 24 valve.

I really need to proofread...lol
 

HotRodPC

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I really need to proofread...lol

That's what the edit button is for. Go back and change it.


So I take it your new truck to tow the house is 24v common rail..:eek: Dodge??? :sad72:
 

wildcatjason

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That's what the edit button is for. Go back and change it.


So I take it your new truck to tow the house is 24v common rail..:eek: Dodge??? :sad72:

Lol yeah to much effort....this truck is nice and has plenty of power for that "house". When the burb couldn't take it though the overpasses of okc. This dodge drove it over the Rockies on i70. It's about the driveline both made by cummins not the truck. One has two more cylinders and computer controlled. I'm gonna drive the piss out of it and rebuild again. It may go in something else though we'll see.
 

HotRodPC

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Towing that "House", you'll rebuild that chassis 3 times around that Cummins drivetrain before you need to build the Cummins Powertrain. Did you get the NV manual trans or Aisan Auto? Dana or AAM axle in the rear,? See, Dodge don't build **** in their powertrains. Which is fine. If you can't build your own ****, at least concede and go with someone who can. Even Ford took over building their PowerStroke from Navistar. Of course they tried with the 6.0 and 6.4 too then tried blaming the failure on Navistar, then Navistar blamed Ford, and that's where that relationship fell apart, so now that Ford learned their lesson and think they don't need Navistar anymore, now the 6.7 Scorpion is all Ford. Hopefully after all these friggin years they can get it right on their own.
 

wildcatjason

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Towing that "House", you'll rebuild that chassis 3 times around that Cummins drivetrain before you need to build the Cummins Powertrain. Did you get the NV manual trans or Aisan Auto? Dana or AAM axle in the rear,? See, Dodge don't build **** in their powertrains. Which is fine. If you can't build your own ****, at least concede and go with someone who can. Even Ford took over building their PowerStroke from Navistar. Of course they tried with the 6.0 and 6.4 too then tried blaming the failure on Navistar, then Navistar blamed Ford, and that's where that relationship fell apart, so now that Ford learned their lesson and think they don't need Navistar anymore, now the 6.7 Scorpion is all Ford. Hopefully after all these friggin years they can get it right on their own.

I know it is a 48re. Not sure who made it and I have no idea what axles either. I wanted an auto because I already own a stick and didn't want two. If I turn up power the driveline will be a concern but it should hold up at stock levels. The dealership where I bought this truck actually let me take an 11 superduty to go get the house. I can't speak for reliability, but the power was BADASS! The gas mileage sucked but that thing hauled ass it got 14 on the highway and 12 pulling. My dodge gets 20 and 11 pulling, but that ford would have killed it in a quarter and probably top end too. No doubt.
 

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