I recently aquired a 96 F250 from my company. The tranny has issues, grinding while downshifting, sometines while upshifting, also reverse seems to bind/clunk sometimes. I have learned that this tranny uses atf not gear oil, which is what is in it now. Will simply draining the gear oil be enough or should I use some sort of flush? What sort of damage could have been done by having the gear oil instead of mercon? Could the wrong fluid be the source of these issues?

 

Sure its the mazda? I've only seen it in the F250s behind the 302 in the early 90s.



Does it look like that? The more common for what you have ZF has diagonal ribbing.

Either way, get ATF in there, but I'm thinkin you'd need a rebuild.

Adrianspeeder

 

Yeah thats it. This is the 3rd tranny in this truck, maybe during a replacement they put a mazda in place of the zf? Which is more reliable? How hard would it be to switch to a better tranny, and which one would you recommend? Thanks for the reply.

 

300, 302 or 351? 4x4?

If so, your gonna pay a mint for a ZF as thats highly desired by guys like me for swappin in our half ton F150s and Broncs. 4x2 ZFs are pretty cheap by default for the same reason though.

Adrianspeeder

 

300 4X2... Will I need to change crossmember, pressure plate, driveshaft, wiring, anything? Is this above the average shadetree's skill level?

 

I have this same tranny (M5R2)

It screams in every gear except 4th, and pukes tranny fluid everywhere.

 

This sounds like a high quality tranny!

 

Actually I think it is alright. I kinda like the whine when driving around town (on th highway gets annoying) and the rear main seal just needs replacing which is pretty normal for any tranny.

 

m5's are ok tranny's however the atf fluid ford used in them is crap. I use syncromesh in them. If it is making noise in all gears except 4th you have a bad bearing (probably the one linking the input shaft to the output shaft)
I like these transmissions in the 2.3 rangers but in the full size trucks they are a bit small IMO. The zf has it's own set of issues. actually I can't think of a moderm manual transmission I like in a large truck. Nothing really competes with the automatics for strength.
Alan

 

The Rangers/Bseries/Explorers/Navajos/Aerostars use the M5OD-R1 dirtydog. The F-150/Bronco use the M5OD-R2. Totally different tranny.

Adrianspeeder