As most here know we pioneered the first R2.8 into a Defender with one of the pre release 25 beta engines.
We have done more of these Cummins conversions into Defenders than any other shop to date. I put this in smaller projects because this was a transmission swap on a Cummins R2.8 truck we had built from a new galvanized chassis up for the 2019 Expo East tradeshow. It has been our test mule truck for the past couple years. Not only do we have more experience doing the conversions than anyone else, we also have more seat time with the engine in defenders than anyone else, to include off road places like Moab and high altitude in Colorado. The 110 used was originally built using a HD Ashcroft long belhousing R380 transmission and 1.2 Ashcroft transfer case. We re-used that 1.2 for this swap.
With that first truck we used a GM 6L80E 6 speed automatic trans. The GM product and the Cummins engine speak different computer languages and cannot be made to talk. The best compromise for that combination is a stand alone controller with a program/tune that mimmicks inputs to get the trans to work. The transmission is huge and given it needs to be adapted to both the engine and transfercase, the end combination is quite long which is an issue with the R2.8 in a left hand drive defender.
We have been looking @ different automatic options since that first build in 2017.
We have been working through different automatic options for the R2.8 with
Chad Mckinney @ QuickDraw looking for the best possible scenario. We took a 110 to his place in Ohio last year and tried different things and basically eliminated possibilities. Kraig Mackett and Chad dragged me kicking and screaming back to look @ using the ZF 4hp22/24 with eh ( electronic handling). The ZF 4Hp in different versions was used in all of Land Rover's automatic applications from the mid 80's up to the LR3 introduction in 2005 (which used another ZF). We had Dave Ashcroft @ Ashcroft Transmissions build us his hybrid 22 case with 24 internals that he indicates should be strong enough for 330 ft lbs or more (details for this product are on the Ashcroft site). Dave supplied his full kit with center console, clutch pedal delete plate, and Compushift 3 module. The folks @ Compushift have the module set with a J1939 canbus engine as an option. We got a canbus cable from Compushift and I got Brittany Huesman the R28 engineer @ Cummins to help me with where I could pull high and low canbus signals from on the Cummins wiring loom. We made several adjustments to the Compushift programming and after 100 plus miles in several test drives I’m down right giddy with how well it works.The controller is bluetooth and can be monitored and changes made from a smartphone application, some screen shots from the dashboard/ monitoring screen below taken @ 70 and again @ 80 mph.
We used an Allisport auto trans cooler designed to be exactly like the original 97 NAS 90 trans cooler for this same trans in a 1997 NAS 90 Defender, ie keeping the truck exactly as Land Rover designed it except for the Cummins engine. After having built a defender using the GM6L80e and having dealt with the stand alone controller and years of pursuing the perfect tune for that combo, we were quite pleased with the absolute ease of getting the ZF shifting how and where we wanted it to. In short it’s awesome, Chad’s kit to install it was perfect and somewhat ingenious. We immediately ordered two more transmissions from Ashcroft’s this morning.
We utilized a D1/ NAS 90 auto shifter, but with the Compushift controller we have the option of utilizing paddle shifting and different modes.
The ZF is considerably cheaper than using a 6L80e and except for Chads kit uses all readily available Land Rover components which is an emphasis for us with our installs.
The fact that the engine and trans talk is a huge part of why we went this route.
![456247]( "456247")
uphill on a grade in this shot so throttle % and hydraulic pressure slightly higher than shot below.
![456248]( "456248")
![456249]( "456249")
![456250]( "456250")
QuickDraw's prototype ZF to Cummins bellhousing. Fit perfectly. The flexplate bolts to a unique Cummins auto trans ringgear/flexplate utilized in another suv application overseas. Chad includes that ringgear/flexplate with his kit.
We have done more of these Cummins conversions into Defenders than any other shop to date. I put this in smaller projects because this was a transmission swap on a Cummins R2.8 truck we had built from a new galvanized chassis up for the 2019 Expo East tradeshow. It has been our test mule truck for the past couple years. Not only do we have more experience doing the conversions than anyone else, we also have more seat time with the engine in defenders than anyone else, to include off road places like Moab and high altitude in Colorado. The 110 used was originally built using a HD Ashcroft long belhousing R380 transmission and 1.2 Ashcroft transfer case. We re-used that 1.2 for this swap.
With that first truck we used a GM 6L80E 6 speed automatic trans. The GM product and the Cummins engine speak different computer languages and cannot be made to talk. The best compromise for that combination is a stand alone controller with a program/tune that mimmicks inputs to get the trans to work. The transmission is huge and given it needs to be adapted to both the engine and transfercase, the end combination is quite long which is an issue with the R2.8 in a left hand drive defender.
We have been looking @ different automatic options since that first build in 2017.
We have been working through different automatic options for the R2.8 with
Chad Mckinney @ QuickDraw looking for the best possible scenario. We took a 110 to his place in Ohio last year and tried different things and basically eliminated possibilities. Kraig Mackett and Chad dragged me kicking and screaming back to look @ using the ZF 4hp22/24 with eh ( electronic handling). The ZF 4Hp in different versions was used in all of Land Rover's automatic applications from the mid 80's up to the LR3 introduction in 2005 (which used another ZF). We had Dave Ashcroft @ Ashcroft Transmissions build us his hybrid 22 case with 24 internals that he indicates should be strong enough for 330 ft lbs or more (details for this product are on the Ashcroft site). Dave supplied his full kit with center console, clutch pedal delete plate, and Compushift 3 module. The folks @ Compushift have the module set with a J1939 canbus engine as an option. We got a canbus cable from Compushift and I got Brittany Huesman the R28 engineer @ Cummins to help me with where I could pull high and low canbus signals from on the Cummins wiring loom. We made several adjustments to the Compushift programming and after 100 plus miles in several test drives I’m down right giddy with how well it works.The controller is bluetooth and can be monitored and changes made from a smartphone application, some screen shots from the dashboard/ monitoring screen below taken @ 70 and again @ 80 mph.
We used an Allisport auto trans cooler designed to be exactly like the original 97 NAS 90 trans cooler for this same trans in a 1997 NAS 90 Defender, ie keeping the truck exactly as Land Rover designed it except for the Cummins engine. After having built a defender using the GM6L80e and having dealt with the stand alone controller and years of pursuing the perfect tune for that combo, we were quite pleased with the absolute ease of getting the ZF shifting how and where we wanted it to. In short it’s awesome, Chad’s kit to install it was perfect and somewhat ingenious. We immediately ordered two more transmissions from Ashcroft’s this morning.
We utilized a D1/ NAS 90 auto shifter, but with the Compushift controller we have the option of utilizing paddle shifting and different modes.
The ZF is considerably cheaper than using a 6L80e and except for Chads kit uses all readily available Land Rover components which is an emphasis for us with our installs.
The fact that the engine and trans talk is a huge part of why we went this route.
uphill on a grade in this shot so throttle % and hydraulic pressure slightly higher than shot below.
QuickDraw's prototype ZF to Cummins bellhousing. Fit perfectly. The flexplate bolts to a unique Cummins auto trans ringgear/flexplate utilized in another suv application overseas. Chad includes that ringgear/flexplate with his kit.
