Who has done a 4BT swap?

[Dieselwrencher]

It varies, but after the swap is always better. My wife's V10 excursion went from 6-11 to 18-20. An 89 V2500 suburban with a TBI 350 to a 12v was 8-12 before, and 15-18 now. And that truck has 3.54 gears with 35" tall tires. He tows a 10k dump trailer with it and a pretty good sized enclosed trailer with it and said he could never go back to the gas engine in it. My 72 I can't tell you before because it didnt run when I got it. But it was a 402 4 speed truck. It gets 17 with a mix of highway and in town driving. I hauled a skid loader a hour and a half away, which was 23k loaded. When I filled the tank from that trip it averaged 14.8. I was running 70-75 on the interstate. It would get better if I pulled some fuel back. It is pretty over fueled right now. I have not dyno'd it but it pulls like any other 600-650hp truck we've built. You have to watch your skinny pedal. The rotary pump 12v's do better on mileage than the P-pump 12v's. But the p-pump engines still get great mileage too.

[Jrgunn5150]

Today, right now, in 2017, I wouldn't swap a diesel into anything.

Gas is cheap, and diesel's are expensive. Given a choice between a Duramax and an 8.1 truck with the same miles, the dmax being cheaper, I took the 8.1, and am pleased as punch.

Back in 2006, I swapped a K5 with a 4BT. I paid 2300 for the entire stepvan, scrapped the aluminum from the body for 1,200, sold my old 350/700R4 for 600, sold the TH400 from the van for 400. That brought me down to 100 for the engine, after everything I was into the swap for around 1,000. It had 3.08's, got around 18 mpg, cruised at 75 easily.

It was not faster than a 454, it was about as fast as a healthy 350.

Now, that you have brodozers and every kid on Instagram #rollincoal with 9" stacks and crap, you can't touch a bare 4bt for less than 2k. It's way to costly to ever make sense financially.

[andrewmp6]

I have looked up stock mpg on trucks gas vs diesel and the diesel always got better mileage.14.8mpg loaded like that is insane to me,My brothers 4x4 f150 don't even get that unloaded highway and its bone stock.As far as fuel prices for a long time here diesel was more then gas but now its a few cents cheaper,But if i go to a truck stop here diesel is even cheaper then a standard gas station.

[Edahall]

duplicate

[Edahall]

Just did a 3000 mi road trip on the Suburban in my signature with a V-pump 6BT and got 29 mpg overall hand calculated I drove no faster than 65 mph but generally 60 mph, weather was good / no head wind, A/C was used minimally and tires were pumped up to 80 psi. All these factors added up to this insanely high fuel economy. I do know that if I drove the 80 mph speed limit, my numbers would have been much lower, probably less than 18 mpg.

[andrewmp6]

29mpg in basicly a brick on wheels is insane to me.

[Jrgunn5150]

Originally Posted by andrewmp6

29mpg in basicly a brick on wheels is insane to me.

60-65 mph speeds were a major factor lol

[DieselSJ]

Originally Posted by Jrgunn5150

60-65 mph speeds were a major factor lol

The double overdrive doesn't hurt either. What RPM are you turning?

I'd absolutely do a diesel swap again and I'm trying to decide what I want to do in the R30. I want to shy away from a 6bt and do something different (like I did with the 6.5 into my Jeep) because there are so many Cummins swaps, but it is hard to beat the power and reliability of an old mechanical injected Cummins.

My Jeep got 12-13 mpg stock. I now get 21-22 through daily commute and I can pull 24 on the highway at 75mph, plus I have tons more power.

[Dieselwrencher]

Originally Posted by DieselSJ

The double overdrive doesn't hurt either. What RPM are you turning?

I'd absolutely do a diesel swap again and I'm trying to decide what I want to do in the R30. I want to shy away from a 6bt and do something different (like I did with the 6.5 into my Jeep) because there are so many Cummins swaps, but it is hard to beat the power and reliability of an old mechanical injected Cummins.

My Jeep got 12-13 mpg stock. I now get 21-22 through daily commute and I can pull 24 on the highway at 75mph, plus I have tons more power.

Like you, I have been looking for a different engine to swap into my next build. I was going to do a 7.3 powestroke in my 40 Ford. I just can't stomach the high price parts for them compared to the cummins stuff. And it is so hard to find a reasonably priced Dmax. I'll probably use my CR 5.9 in the next build. Or maybe do a LSX swap if it is a car. But these are more common than a cummins swap IMO.