Cummins 2.8T Diesel Engine Swap

[120mm]

330 pounds lighter than a 4BT, and the entire package comes in under $9k.

I think I need this.

Anyone done this swap yet?

 

[Varty Yo]

Oh just a few here.....

 

[archie73]

330 pounds lighter than a 4BT, and the entire package comes in under $9k.

I think I need this.

I get the desire for this engine: new, mpg, crate, looks pretty complete from that video and the list goes on. I’m still shocked at the appeal:

• $9k buys a lot of power and torque in other engines.
• I know it’ll still be running for a long time, but I don’t put that many miles on anyway.
• The promise of mpg is always alluring, but I circle back to the last thing I said.
• Adapters aren’t included for 9 large
• Stock power output isn’t that impressive. I’m sure there are a slew of tuners that’ll bump it up, further increasing price tag.

I’m not saying you or anyone else shouldn’t do this swap. I’m just not sure I understand the appeal. And to be fair, I’m not a diesel guy either. Veg sounds neat (my buddy drives his F350 for free), but I couldn’t take that chance on a $9k engine. Maybe I’m stuck on the $9k

 

[Sheck44]

I know someone ... wink wink
Steve

 

[1911]

330 pounds lighter than a 4BT, and the entire package comes in under $9k.

I think I need this.

It's on my wish list, when/if I ever give up on my 2F.

Anyone done this swap yet?

There are a few threads and builds (more in 60 and 80-series); if you search mud for "Cummins 2.8" you will find them.

 

[John in Utah]

I get the desire for this engine: new, mpg, crate, looks pretty complete from that video and the list goes on. I’m still shocked at the appeal:

• $9k buys a lot of power and torque in other engines.
• I know it’ll still be running for a long time, but I don’t put that many miles on anyway.
• The promise of mpg is always alluring, but I circle back to the last thing I said.
• Adapters aren’t included for 9 large
• Stock power output isn’t that impressive. I’m sure there are a slew of tuners that’ll bump it up, further increasing price tag.

I’m not saying you or anyone else shouldn’t do this swap. I’m just not sure I understand the appeal. And to be fair, I’m not a diesel guy either. Veg sounds neat (my buddy drives his F350 for free), but I couldn’t take that chance on a $9k engine. Maybe I’m stuck on the $9k

Finally someone says it! MPG means literally nothing at that price tag. Buy a 350 and put the other 8k in a gas fund.

Many good Toyota options out there for half this price, and most times you get a H55 to boot!

...And I wouldn’t even think about putting WVO into a diesel that modern.

 

[J Mack]

Finally someone says it! MPG means literally nothing at that price tag

Can you explain literally nothing, maybe I’m missing your point.

I could kind of understand your logic if you spend your days circling a gas station and you had to pull in every third loop with a SBC vs every four loops with a Cummins 2.8T then yes it would be hard to justify.

For those of us that use our off road vehicles off road on extended trips MPG + capacity = range, I tripled my range switching from a SBC to a Cummins so MPG means literally everything when planning our trips and the distance we can stay off grid.

 

[archie73]

For those of us that use our off road vehicles off road on extended trips MPG + capacity = range, I tripled my range switching from a SBC to a Cummins so MPG means literally everything when planning our trips and the distance we can stay off grid.

This is a good reason to go diesel. It still doesn’t give me reason to do the R2.8, possibly a Toyota, VW or 4BT. I could triple my mileage with an auxiliary gas tank.
Like I said, I’m just stuck on the price tag of this motor. @Sheck44 and others, I enjoy watching your builds and respect your right to do what you want.

 

[John in Utah]

Can you explain literally nothing, maybe I’m missing your point.

I could kind of understand your logic if you spend your days circling a gas station and you had to pull in every third loop with a SBC vs every four loops with a Cummins 2.8T then yes it would be hard to justify.

For those of us that use our off road vehicles off road on extended trips MPG + capacity = range, I tripled my range switching from a SBC to a Cummins so MPG means literally everything when planning our trips and the distance we can stay off grid.

My bad, I need to be more careful using the word literally. An auxiliary fuel tank and a handful of jerry cans solves your range issue though.

 

[J Mack]

I could triple my mileage with an auxiliary gas tank.

You are correct and I did both, tripled my MPG and doubled my fuel capacity when switching from gas/SBC to Fuel/Cummins.

The Cummins swap isn’t for everyone and having done one myself I would argue a LS swap probably makes more sense especially if you have a limited budget. For a guy wanting a Cummins the 2.8T is going to be a better option than the 4BT, you get a lot for 9K and you would be hard pressed to buy a 4BT then rebuild it to new for the same money not to mention the size difference (the 4BT is tall making fitment a challenge without going spring over or some other suspension modification)

My bad, I need to be more careful using the word literally. An auxiliary fuel tank and a handful of jerry cans solves your range issue though.

No bad I was just trying to get a better understanding when you said “Finally someone says it! MPG means literally nothing”. Thanks for the clarification!

FYI that’s a lot of Jerry cans when your SBC gets single digit MPG and that space could be better used for other gear but I see your point.

 

[John in Utah]

No bad I was just trying to get a better understanding when you said “Finally someone says it! MPG means literally nothing”. Thanks for the clarification!

I shouldn’t generalize like that though. Often times folks are using gas mileage to justify the cost of the swap, which is what my MPG comment was aimed at. I love my little turd of a diesel but it’s about as practical as it is fast.

I wasn't thinking in terms of range and I apologize for leaving that consideration out.

 

[1911]

For those of us that use our off road vehicles off road on extended trips MPG + capacity = range, I tripled my range switching from a SBC to a Cummins so MPG means literally everything when planning our trips and the distance we can stay off grid.

For me, it's the torque down low for wheeling. The 2.8T reaches it's peak torque of 310 ft.lbs. at only 1800 rpm, and gives 80% of peak torque well before that and usable torque right off of idle (similar to a 2F torque curve but with 50% more torque). The SBC has to spin up to what, 4-5,000 rpm (I'm guessing) to get peak torque? Torque from off idle to 1800 rpm is way more useful on the trail than torque that you have to rev way up to get. The increase in fuel economy is a bonus, but not the reason to do this conversion IMO.

 

[CBeckFJ]

the 2.8 is nice. Considered it. God i wish the v8 diesel in the 70 series was legal

 

[Cuda519]

Just put one in my wife’s Jeep yes I know I said a bad word... but it is very strong runs 35s 70 mph no problem and so far she loves it

 

[120mm]

For me, it's the torque down low for wheeling. The 2.8T reaches it's peak torque of 310 ft.lbs. at only 1800 rpm, and gives 80% of peak torque well before that and usable torque right off of idle (similar to a 2F torque curve but with 50% more torque). The SBC has to spin up to what, 4-5,000 rpm (I'm guessing) to get peak torque? Torque from off idle to 1800 rpm is way more useful on the trail than torque that you have to rev way up to get. The increase in fuel economy is a bonus, but not the reason to do this conversion IMO.

THIS is exactly what I was thinking. LS torque in a real off road vehicle is pretty unimpressive. High horsepower in off road vehicles has limited real world utility. What really makes the R2.8 for me, is it's small size, it's driveability, and where it gets its torque.

Fuel costs in these kinds of vehicles really doesn't matter. It is the least significant cost in a special interest vehicle. Conversion and maintenance costs are the big eaters of $$$.

Also, don't forget simplicity. I drive my Pig every day. At some point, I am going to park it, fix all the niggling faults and rust outs. My plan is to make it a "forever vehicle" for me. No way is the 2F supported well enough to be the engine that will do that.

I like the range potential as well. You may say "just add extra tanks and jerry cans" but that's apples and oranges. I'm going to do that AND have efficient diesel power when it's all over.

 

[JohnBoy]

BTW, what type of mileage does a SBC get with that yoda 4-speed and 4:11's? Was curious about that.

 

[1911]

Here's a new thread of a shop putting one in a 40:

67 R2.8 Restomod Build

 

[tls3601]

I think the biggest argument is how many miles you plan on driving your 40. Most, not all folks don’t take long trips in them or extended jaunts off pavement. If you put on loads of miles then the 2.8 argument becomes stronger.

 

[drnekFJ40]

One of my friends bought a newer vehicle( small car)for the reason of saving a gas money with it...The difference in the price of the older vehicle he already owned and newer more economical vehicle was a sum of money which if you convert to gas savings he would brake even in 12 years and starting saving gas money after it...I told him that is a crazy reason to buy a vehicle for...So if you pay 9K + maybe another 5K? in other parts for 2,8 cummins swap- MPH really doesn"t matter -it will take so long to justify the cost of swap in gas savings (having more economical engine in your vehicle) that it does not make sence...Yes-torque and longer range and parts availability-that should be the main reason for the 2,8 cummins swap

 

[jim land]

And what about the VW swap vs the cummins r2.8

Price
Hp and torque specs
Adapter and wiring
Easy to find new or used parts
And more