Either one of the above will probably work unless you have a two motor setup and need the RPMs to match the other leg. Try to get the faster one that matches your OEM but if it's an emergency, you can probably get away with the slower motor and upgrade later if desired. I recently upgraded to a dual motor setup and I highly recommend it. It's a fairly simple job to replace the motor. Lots of videos on youtube explaining the process.
2020 Chevy Silverado 3500HD Duramax 4x4 Crew Cab Standard box
2011 Arctic Fox 27.5L
