i have an 05 cummins and i was wondering how much it would cost to convert my truck over to a manual transmission?

 

I don't know a figure for you but this is a huge job. Are you going to do it yourself or pay a shop? You would need the clutch peddle and assembly, transmission, driveshaft or shafts if four wheel drive probably move a crossmember or two. Install a shifter and all the linkages. I'm sure I missed a bunch but you would almost need a donor truck to get all the parts off of. I would think you would easily have 3-5,000$ in a project like this. Might be easier and cheaper to just trade it in for what you want.