Hd8 no high gear

[Hd8]

Was told by s shop there is an internal issue with my transmission/gear box. All adjustments are correct and have metal flake in tranny fluid. They want to charge a lot of money to open and make repairs. Was thinking of purchasing a rebuilt and installing myself. Does anyone know if I can use different models such as hd10 or any different years 2016-2020? Thank you all

[Steelslinger]

Look at the part numbers. I'd say be careful 2019 and prior model years going onto 2020+ model years, as the engine is a different part number (mainly due to the extra mounts and stuff for the AC system). My understanding is the trans cases are all the same between models, just different internals for XMR vs the rest.