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Cummins R2.8

The Do's and (mostly) the Don'ts of Cummins conversions...

PLEASE NOTE: We have had conversion inquiries coming in for the R2.8 Cummins engines and rather than explaining to each and every person why we do not offer the R2.8 engines as a conversion option, we simply send them a link to this page.

  When Cummins announced the R2.8 crate engine program at SEMA in 2016. These sounded like the ultimate setup. Among the many features promised,  we were told that these brand new crate engines would carry an emissions compliance certificate and  legendary Cummins reliability. We were excited! The Cummins reps that we spoke to at the SEMA show were also touting a $5000-6000 purchase price which was really unbelievable. So, we quietly began researching anything we could find on the platform. We purchased a complete 2.8 ISF from overseas, flew overseas to speak with people with real-world experience with these engines, explored reliability numbers, and even completed a prototype conversion. Our findings were NOT good…

  The R2.8 is entirely built and assembled in China. Starting in 2009, the 2.8 ISF engines were licensed and installed into Chinese Foton Tunland pickups. The 2.8 ISF has an absolutely TERRIBLE reputation in overseas markets. Premature connecting rod failures, bad injectors, turbocharger failures, the list goes on and on. In fact, everyone we spoke with about the 2.8 had nothing but bad things to say about them. Next,  we went at this from a parts perspective. We wanted to know once the Cummins warranty runs out,  how difficult are parts to get for these things? Impossible in fact. We found that the ONLY vendors selling parts are Chinese vendors on and they all wanted wire transfer payments and none of them spoke English. We contacted our local Cummins dealers and they both had no parts inventory of any kind nor did they even list the parts in their databases. Since these engines are not sold here, nobody stocks parts. We asked our Cummins reps directly if they would sell us parts and they don’t even find most of the parts for these engines in THEIR system. So, on parts that was also a FAIL.

  In late 2017, Cummins finally released the R2.8 Crate Engine Program.  Sadly, Cummins had almost doubled their initial price estimate than what we were told at the SEMA show, the engines carry no emissions compliance certificates for vehicles newer than 1999,  and incredibly only carries a 90 DAY WARRANTY! We were floored…With a purchase price just shy of $10,000 and  a warranty that will run out before you get it functionally installed, who is their target market? The R2.8 Crate Engine Program includes no provisions for transmission, no controllers for anything, no cooling system, nothing. For $10k all you’re getting is an engine with a piggy-back wire harness and accelerator pedal. That’s literally it! This means that putting that engine into ANYTHING other than a 30 year-old Jeep will require a ton of development, a standalone transmission controller, air conditioning system provisions, cooling system, air cleaner, intercooler system, mounting system, adapters for the transmission,  the list goes on and on... Most modern (2005+) vehicles have computers for pretty much everything. So, getting cruise control, air conditioning, ABS systems to all function with the R2.8 will require custom computer boxes with custom-code written in them. This means ULTRA EXPENSIVE…

  Sadly, in our opinion the Cummins R2.8 Crate Engine Program is DOA. They are crazy expensive, will be an extraordinarily difficult installation as everything will need to be hand-built, and only carry a 90-day warranty. We have been in the diesel conversion business for almost 17 years so our experience is unmatched in the industry. From a professional conversion company’s perspective, the Cummins R2.8 conversions will LOOK like conversions and will not have the stock fit & finish we’re known for. Franken-swaps are not in our DNA and we don’t feel that is something paying customers want.  We asked ourselves, “who on earth wants to pay to install a Chinese R2.8 engine into their Toyota when they can get a factory Toyota D-4D engine with legendary reliability and power for less money”?  Our approach has always been minimalist as nothing can compare to the factory designed stuff and the more one deviates from this the more the conversion starts looking like a franken-swap and the reliability of the finished product goes way down.


  We wrote the above article in 2017 and it has proven to be 100% accurate. We have learned that after 7+ years of selling these engines, Cummins is discontinuing them entirely due to poor sales and warranty claims. Feedback from other shops and customers that have paid other shops to install them has been precisely what we said above. Total junk engines with no support, poor fuel economy, and ultra-expensive for what you're getting. 



Cummins 4B-T aka..”The Paint Shaker”



  We regularly get emails from customers wanting more information about the 4B-T cummins (B3.9) engines. Unfortunately, we dont really have anywhere to send them for comprehensive, real-world,  factual data. Most of the information online is from companies “selling” 4B-T conversions so what IS available is highly biased and factually inaccurate. So, we put together a little fact-checker list.




Top 10 Dumbest Engine Swaps


 A few years back, JP Magazine did an article entitled ” Top 10 Dumbest Engine Swaps” and the little “paint shaker” 4B-T made the list. (FYI we did NOT write this)

Taken from JP Magazine article…

“But again, the noise, vibration, and fumes from one of these little paint shakers will be enough to push most Jeep owners over the edge of the nearest cliff. Plus, they weigh a little more than an all-iron big-block. They sound good on paper, but when you’ve lived with one of these conversions for a little while the buzzing and belching can really test the temperament of some drivers.”



Why is it called “the Paint Shaker”?


  This is a name that we did not come up with, but has been around since the 4BT was introduced. The 4B-T engine was developed by Cummins for use in off-highway stationary generator sets and large heavy-duty delivery vans. They were considered large displacement 4 cylinders touting “1 liter per cylinder” displacement. This was a big deal back in the 1980’s when they were designed. Most passenger vehicle diesel engines are internally balanced which minimizes vibration and internal engine wear.  The B3.9 4B-T Cummins engines are not internally balanced. Due to their large displacement and long stroke, and not having an internal balancing mechanism, the 4B-T shakes far more than your average engine. To combat this issue, a few aftermarket companies have tried to develop liquid-filled engine mount to absorb some of this extreme vibration. Again, the issue is that the engines were not internally balanced.  To be thorough, Cummins did sell an add-on balance shaft module for the 4B-T. These add-on modules have several MAJOR drawbacks when used in a passenger vehicle application. First, they were designed to be operated at a constant RPM and are limited to 1,900 RPM’s. They were also expensive at +$2,000, and difficult to find (even from Cummins dealers). Lastly, they were extremely bulky (requiring the use of a giant oil pan assembly specially designed to fit the balance shaft module) which makes fitment in a passenger vehicle engine compartment literally impossible.



30 mpg?

  This is probably the most disingenuous  aspect of the 4B-T engine swap. We see 4B-T swap companies touting all sorts of astronomical fuel economy numbers online. However, with fuel consumption data from Cummins’ own website and a calculator, one can easily see that these mpg numbers are wildly inflated and completely impractical. Most conversions dont get anywhere near 20MPG much less 30MPG. These 4BT swap companies do this to sell conversions…plain and simple. Don’t believe us? Ask them for a written guarantee on MPG…

Our approach?

  We get emails from some folks wanting to argue about “our approach” to diesel converions and how much they love the 4B-T Cummins engines in their mom’s station wagon, Bronco, etc. Well, the fact is that “our approach” is not really “our” approach at all; it’s the OEM’s that made your vehicle. We ONLY install OEM powertrains found in these vehicles in other countries. So, whether you like or dislike our product really boils down to if you want a fully integrated, no compromises, daily driver that is designed and built by the same company that built your vehicle. Shoe-horning a bread truck engine into your vehicle (while technically possible) NEVER translates into the type of product a professional company wants to stand behind.

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