You’ve Got Questions? We’ve Got Answers!
Please feel free to email us with any questions that you may have. We look forward to helping you with your Cummins swap!
Yes. You’ll need a bell housing adaptor and flex plate to mount the transmission to your engine. There are several manufacturers that offer these. For wiring, tuning and miscellaneous Allison parts, we recommend using www.transmissiontuner.com Precision Industries offers a torque converter specifically designed for that transmission/ engine combination.
The factory style power steering line can be used with the GMT 800 motor mounts regardless if the Dodge vacuum pump is deleted or not. The GMT 400 motor mounts require the Dodge vacuum pump to be deleted. This can be accomplished by using a 4bt style power steering pump mount and drive gear. With the vacuum pump deleted, a factory style power steering line can be used.
Yes. The PCM is retained so that it can communicate the tach signal and vehicle speed to the instrument cluster. HP Tuners or EFI Live can be used to reprogram the PCM, turning off all unused/unnecessary tables and the check engine light. The factory GM oil pressure and temperature sensors will be installed in the Cummins engine. Coolant level and oil level can be retained if desired.
We’ve discontinued the tone wheel kit in favor of using the waveform (W) terminal on the Delco 28SI alternator in combination with the Dakota Digital Diesel Tach Interface ADD LINK IN PLACE OF THESE CAPITALIZED WORDS. This solution has proven to be a great alternative given the added benefit of that alternator’s internal regulator, high amperage rating, strength and low cost.
Yes. It does however require the use of somewhat expensive and hard to find parts. The fan support, pulley, fan clutch and fan from an intercooled first generation Dodge RAM need to be used. Additionally, the heat exchanger fins on the clutch need to be machined down to clear the radiator, and the fan needs to be spaced off of the clutch 5/8″ with a machined spacer. We will be offering the spacer in the future, but they are currently unavailable.
Yes. Inline 6 cylinder engines are inherently long and we position the engine as far rearward as possible to allow the use of a mechanical fan with the cooling pack in the factory location. This positions the transmission roughly 4″ rearward of the factory location. Your rear driveshaft will need to be shortened, and the front shaft will need to be lengthened. The transfer case will need to be indexed upward and the torsion bar cross member will need to be modified to clear the transfer case. The transfer case linkage will need to be modified as well.
I have a 4X4 GMT 400 truck that I’d like to Cummins swap. Does the installation of your motor mounts require modifying my frame?
Yes. There is an offset (raised) area at the bottom of both motor mount saddles that need to be trimmed off. You’ll also need to install countersunk bolts in the 3 uppermost differential case bolt holes. Some trimming of the differential case webbing is required as well.
Our motor mounts will fit in your truck with a fair amount of fabrication work. The pedestals that are welded to the cross member need to be removed. Holes need to be drilled in the cross member to bolt in our lower motor mount. The nuts on the lower mounts would be accessed through the spring pockets. The cross member will need to be relieved so that it will clear the oil pan. The relieved section will need to be boxed and reinforced to restore it’s structural integrity. The cross member is a an integral part of the suspension, therefore these modifications should only be performed by an experienced welder/fabricator.