I have a D60 front and 14Bolt rear with discs. I'm running a 85 E350 M/C with a Summit Racing portioning valve. It works great. Works good enough that I loocked it up and slid 42" TLS's and ended up bending stock YJ springs. Now got RE1445's and it's a beautiful thing. The M/c isn't that expensive either, like $10 with core and $15 w/o core exchange. You have to drill out the mouting bolts and grind down the ears just a little but def. worth it. Good luck.