Jeep Wrangler Diesel Conversion

Unrelenting, Powerful, Effective

There’s no such thing as too much torque…

Offroad Capability

With the diesel engines, power comes in at a low RPM giving you all the power you need right off of idle.

Fuel Economy

Not only will the diesel increase you fuel economy, but you even have the option of running alternative fuel sources like WVO.

Proven Reliability

The Cummins name is known for reliability, you simply cannot kill a Cummins.

Cummins Diesel Options

Cummins 4BT

3.9L 4BT Diesel Conversion

The Cummins 4BT turbo diesel is the perfect option for the Jeep enthusiast looking to improve their fuel efficiency and off-road capability. In addition to boasting increased fuel efficiency, the 4BT is also capable of running alternative fuel sources like Waste Vegetable Oil. All year Wranglers can be converted up to 2011 along with a few other make and models.

The Cummins 4BT is one of the most proven diesel engines in the world. If well maintained, one can expect to get 300,000 miles out of their engine with 500,000 miles not being uncommon. Our standard conversion includes a rebuilt Cummins 4BT with the option of using a used or new model if the client prefers.

The stock transmission is replaced as part of the 4BT conversion. We utilize either a 4l70e HD automatic transmission or NV4500 manual transmission depending on the clients transmission preference.

The only extra costs that a client may incur are transportation fees and suspension upgrade. We do transport vehicles all over the country and even internationally, we can provide an accurate quote for transport with the pickup/dropoff zip codes. Our conversions do require at least a 2.5” lift which is not included in the cost of the conversion. This cost is not included because many of clients either already have a lift or are looking to do a more aggressive system.

Starting at…

28
AVG MPG
360
FT/LBS

4BT Specs

ConfigurationInline 4 Cylinder Turbo Diesel
Displacement3.9 L, 239 Cubic Inches
Bore4.02 inches
Stroke4.72 inches
Compression Ratio17.5:1
AspirationTurbo Charged, Non Intercooled
Engine Weight725-765 lbs
Oil Capacity10 Quarts
Horsepower105-170 hp@ 2300 RPM
Torque265-420 ftlbs@ 1600 RPM

Detailed Information

The years of the Jeep Wrangler model that can be converted at present are 2007 to 2011. We remove the stock engine and transmission and replace it with a Cummins 4BT and stronger transmission. Below we will discuss some of the kit components in greater detail.

The kit utilizes a mechanical bell crank assembly with Lokar stainless throttle and t.v. cable for transmission (also known as a kick down cable). In addition it uses a bracket for floor board to accept a manual throttle pedal.

Our custom A/C and alternator bracket enables the conversion and reuse of the existing AC compressor and alternator from the 3.8L. The serpentine belt is upgraded to an 8-groove belt, along with, an upgraded 8-groove A/C clutch and 8-groove alternator. The a/c lines are custom to retrofit to the factory compressor in its new location.

The battery tray is custom made to relocate the position of the battery and the fuse /relay box for proper clearance of the cold air intake and turbo. The wiring harness is completely re-engineered to control all engine functions as well as communicate with factory ECM through a S.I.M. (Systems Integration and Management) computer.

The engine mounts are engineered to remove most of the vibration from the 4BT. This is accomplished by utilizing a fluid filled mount located in the custom built engine mounting bracket assembly. The assembly itself is designed to maintain the engine’s torque and remove all harmonics.

The factory gear driven power steering pump for the 4BT is utilized and conversion high pressure and return lines are custom made to connect to the factory power steering gear. The pump also makes enough pressure to operate all after market ram assist or full hydraulic steering arrangements; this is because it did control a hydro assist system.

The factory radiator and fan assembly is reused because the 4BT does not require an extreme cooling system to maintain the proper temperature range of 180 degrees. The lower water neck is replaced with a custom built unit that allows you to reuse the factory lower hose from the 3.8 and the upper hose is replaced with a new unit.

The braking system is controlled by a billet housing custom vacuum system.

There are two options for transmission. For those wanting an automatic transmission, we offer the 4L60E with Compushift. For those wanting a manual application, we offer the NV4500. Both of these transmissions are bulletproof units that can handle the extra torque of the 4BT.

The transmission is mated to the factory transfer case through a custom adapter and newly broached tail-shaft assembly. The cooling lines are custom for transmission, as well as, all brackets to attach factory shifter cable to transmission and transfer case. This also allows you to reuse the existing transmission and transfer case shifters in their factory positions.

The factory mount is used to mate with the factory cross member through a custom mounting bracket, which allows you to re-use the factory length drive shafts with up to a 6 inch lift.

Cummins_4BT_3.9L

The 4BT is one of most proven reliable diesel engines in the world. If well maintained, it is not uncommon for these engines to last 350k – 500k miles. They are also a very common engine making it easy and affordable to repair should anything break.

We have a variety of power options for those seeking to upgrade their application.

4L60-Transmission

4L70E HD – This automatic transmission is capable of holding 850 ft. lbs. of torque.

NV4500 – This manual transmission is a proven warrior. It has been used predominately in diesel applications for years and is one of the best manual transmissions ever produced.

Bosch VE Pump

  1. Bruiser fuel pin 40-60 HP / 80-100 ft/lb
  2. Prince of darkness injectors 30-50 HP / 80-100 ft/lb of torque
  3. Turbo upgrade H1C 30-50 HP standard
  4. Different Turbo chargers and exhaust housings can be utilized to enhance reaction time for quick spooling example 12 cm exhaust housing w/ H1C gives quicker spool up which gives better bottom end. There are many different applications for different driving characteristics.
  5. Injectors- Stage 1 (Prince of darkness) Injectors increase 30-50 HP / 80-110 Ft/lbs. of torque
  6. Many factors determine Horse Power and Torque. With customer technical support we can determine what the best option is for your application.
  7. Camshaft upgrades are available.
  8. Several different transmissions including manual and automatic depending on customers desired application.
  9. Valve springs, push rods, rocker arms, custom exhaust manifolds
  10. Bruiser Down tubes 2.5 inch to 3 inch
  11. Spring upgrades to 3200 rpm for injection pump
  12. Remote Fuel filter and water separator relocation brackets and assemblies
  13. Remote Oil filter Relocation brackets and assemblies
  14. Air to Air cooler, After cooler and all accessories with Bruiser cone style K-n-N air cleaner assembly
  15. Bruiser air box
  16. Snorkel assemblies available

P-7100 Pump

  1. P7100 Inline Pump- Fuel Plate 20-110 hp / 60-215 Ft/Lb of Torque
  2. Prince of Darkness injectors 30-50 HP / 80-100 Ft/lb of Torque
  3. The rest is the same as 4BT VE Pump Application.
3.9L ISB

3.9L ISB Diesel Conversion

The Cummins ISB is an exciting option for Jeep Wrangler owners with a 2007+ model Jeeps. The 3.9L Cummins ISB is also known as the common rail 4BT. Additionally, the ISB is an electronically controlled engine allowing it to fully integrate with the Jeep.

The Cummins ISB turbo diesel increases fuel efficiency and allows for alternative fuel sources like Waste Vegetable Oil. Additionally, the low-end torque makes for a great off-road power plant. One of the perks of the ISB is that it is a good bit quieter than the Cummins 4BT.

The Cummins series of diesel engines are known for their reliability. If well maintained, these engines can expect to run 300,000 miles or greater. Our standard ISB conversion includes a rebuilt Cummins ISB. The stock transmission is replaced as part of our Cummins ISB. Our baseline Cummins ISB conversion includes an Allison 1000 transmission.

The only extra costs that a client may incur are transportation fees and suspension upgrade. We do transport vehicles all over the country and even internationally, we can provide an accurate quote for transport with the pickup/dropoff zip codes. Our conversions do require at least a 2.5” lift which is not included in the cost of the conversion. This cost is not included because many of clients either already have a lift or are looking to do a more aggressive system.

Starting at…

26
AVG MPG
420
FT/LBS

ISB Specs

Horsepower170 hp @ 2600 RPM
Torque420 ftlbs @ 1600 RPM
Cummins 3.8 ISB

3.8L ISF Diesel Conversion

The Cummins ISF is an exciting option for Jeep Wrangler owners with a 2012+ model Jeeps. The 3.8L Cummins ISF is an electronically controlled engine. The Cummins ISF turbo diesel increases fuel efficiency and allows for alternative fuel sources like Waste Vegetable Oil. Additionally, the low-end torque makes for a great off-road power plant. One of the perks of the ISF is that it is dramatically quieter than the Cummins 4BT.

The Cummins series of diesel engines are known for their reliability. If well maintained, these engines can expect to run 300,000 miles or greater. Our standard ISF conversion includes a brand-new, crate Cummins ISF. The factory NAG1 is used with these conversions.

The only extra costs that a client may incur are transportation fees and suspension upgrade. We do transport vehicles all over the country and even internationally, we can provide an accurate quote for transport with the pickup/dropoff zip codes. Our conversions do require at least a 2.5” lift which is not included in the cost of the conversion. This cost is not included because many of clients either already have a lift or are looking to do a more aggressive system.

Check out our dyno results.

Starting at…

35
AVG MPG
485
FT/LBS

ISF Specs

Horsepower170 hp @ 2600 RPM
Torque485 ftlbs @ 1300 RPM

Browse Our Gallery of Diesel ConversionsView Gallery

Diesel Conversion Pricing

 
3.9L 4BT
3.9L ISB
3.8L ISF
Horsepower105 @ 2600rpm170 @ 2600rpm228 @ 2600rpm
Torque360 @ 1600rpm420 @ 1600rpm485 @ 2150rpm
Warranty1yr. / 12,000 miles1yr. / 12,000 miles1yr. / 12,000 miles
JK 2012+--$29,500$29,500
JK 2007-2011$20,500$29,500--
TJ 1997-2006$20,500----
YJ 1987-1996$17,500----
CJ5, CJ7, CJ8$17,500----

4BT Options

Boost & EGT Gauge Pillar$1000
P-Pump
(135hp/400ftlbs)
$2500
Transmission Conversion$3500

FAQ

Is the diesel conversion street legal?

Our engine conversions are available as an “off-road only” application. We make no assertion that our conversions are street legal. This is not due to any mechanical limitation, but solely due to compliance with federal regulations regarding emissions and motor vehicle compliance. For further information please contact your local DMV.

What is the closest Bruiser Conversions location?

Currently, the only Bruiser Conversions location is in Clearwater, FL. We are quite accustom to transporting vehicles across the country and even internationally. All we need for an accurate transport quote is a zip code or destination port.

What other modifications are needed?

The only modification that our diesel conversions require that is not included in the price is a suspension lift. The reason we don’t include the lift in our pricing is because many of our customers already have a lift or are planning on doing the lift when they get the conversion. A lift only needs to be 2″ in many cases but can be bigger if the client desires.

What performance upgrades are available?

We offer a variety of performance upgrades. If you are interested in cranking up the performance of your engine, we recommend scheduling a phone call with one of our engineering techs to discuss options and cost. Simply give us a call or send us an email for scheduling.