txheat,
This is one of the things I ran into when I bough my wash back in January. I knew a lot of my HP hoses were old and would need replaced sooner or later. After having my local John Deere service center make me a 2 foot HP hose (Cost of $25 bucks) I decided to source my own HP hose, ends, and a Hydraulic Crimping Machine. What I learned is, a crimping machine or the dies for that machine will only crimp ends made for that die, or visa versa. The ends at John Deere are not the same as the ones I bought online or ones that will work with my crimper. There is a pretty close limit as to the finished crimped diameter of the fitting so you know the right grip is applied to the hose and the fitting won't "Blow" off. In my case there is about a .010" limit after the fitting is crimped. So in this case you'll want to do some homework to make sure the hose, fittings, anmd crimper are all compitable.
I try to stay away from JIC ends as these are straight thread and use a compression style fit of 37°. I like to use pipe thread to keep it simple. My HP hose is 3/8 ID and the hose fittings on each end are either 3/8 pipe or 3/8 pipe swivel, depending on apllication. This will keep things as simple for you as possible. Hope this helps...
Jeff