what do you guys use for fluid in the m5od trans? how much

[rboyer]

Any idea about the fluid?

Your 03 should have the carbon fiber synchros which means Mercon V would be your fluid of choice. It's the older ones with the brass synchros that require Mercon III although you can run Mercon V in them but they will shift like crap.

 

[rboyer]

As for the people that run gear oil or motor oil in the M5OD's, run the stuff for a couple of years and then drop your trans, pull off the top cover and take a look inside. That black "film" that it leaves all over should be enough evidence that it isn't healthy.

 

[darkspork]

Your 03 should have the carbon fiber synchros which means Mercon V would be your fluid of choice. It's the older ones with the brass synchros that require Mercon III although you can run Mercon V in them but they will shift like crap.

So would "Mobil 1 Synthetic ATF" be a good fluid to use? It says "suitable for use in vehicles that specify the following fluid requirements: Ford* MERCON*, MERCON V, MERCON LV * Not recommend for CVT applications, Mercon® SP, Ford Type F" on their website. It also lists a whole lot of other manufacture specs it meets but my primary interest is the Ford. Also, in what year was the switch to carbon fiber synchros made?

 

[rboyer]

So would "Mobil 1 Synthetic ATF" be a good fluid to use? It says "suitable for use in vehicles that specify the following fluid requirements: Ford* MERCON*, MERCON V, MERCON LV * Not recommend for CVT applications, Mercon® SP, Ford Type F" on their website. It also lists a whole lot of other manufacture specs it meets but my primary interest is the Ford. Also, in what year was the switch to carbon fiber synchros made?

The Mobil 1 Synthetic stuff should work just fine. As far as the switch to carbon fiber synchros, I *think* it took place sometime in 2001.

 

[darkspork]

The Mobil 1 Synthetic stuff should work just fine. As far as the switch to carbon fiber synchros, I *think* it took place sometime in 2001.

2001 as in no later than 2001? Or would a be better off just using a plain Mercon ATF to be safe? According to the transmission guide it is 2001 that the M50D-R1HD started being used in the ranger. Do all of the M50D-R1HD transmissions use the carbon fiber synchros?

 

[wahlstrom1]

I'd just use plain Mercon ATF to be safe. I ran 50W synthetic in mine AFTER he synchro's were starting to pile up, but went back to ATF on my replacement tranny and it's quiet and shifts great.

-andrew

 

[darkspork]

I'd just use plain Mercon ATF to be safe. I ran 50W synthetic in mine AFTER he synchro's were starting to pile up, but went back to ATF on my replacement tranny and it's quiet and shifts great.

-andrew

I'm not sure how the 50W is relevant to Mercon V but in any event I went with "Mobil Multi-Vehicle ATF" which is synthetic blend approved for Mercon. Transmission shifts a lot better and the truck feels a little more responsive. Old fluid was dark brown, some of it looked thick, some thin, seemed bad. If I don't like the synthetic blend I'll just put Motorcraft brand Mercon ATF in since I figured I'd do one transmission drain to drain all the crap out and another one to get the remainder out.

 

[427ford]

As for the people that run gear oil or motor oil in the M5OD's, run the stuff for a couple of years and then drop your trans, pull off the top cover and take a look inside. That black "film" that it leaves all over should be enough evidence that it isn't healthy.

The shop that I got the reman M5 from, recomends 5w30 syn motor oil. I questioned him on that and he states this oil holds up much better in these trannys. Damn if I know.. but I'm real happy with the reman tranny and he 'seemed' to know his stuff.

 

[Anezangl]

5w30 syn motor oil? was there a Green tag hanging on the tranny when it arrived? The one I received last night has a tag calling out 5w30 and I just relized when I read your post it might mean MOTOR OIL?

 

[427ford]

It was installed a few years ago. Don't recall if it was tagged or not. I emailed the rebuilder recently and he confirmed the 5w-30 Syn "motor oil" holds up better than ATF. Just changed it and it shifts fine. Neighbor used it in his Ranger as well, and he said he can feel a difference.

 

[racsan]

ive gone almost 2 years now with the pennzoil syncromesh fluid in the trans, no issues. just changed the transfer case oil. thought about using the pennzoil fluid in it also, but didnt want to take a chance on screwing something up. filled it with mobil 1 syn a.t.f.

 

[Natedog]

ANybody used Lucas ATF additive, supposedly can use up to 50/50 ATF and Lucas? 5w-30 Syn motor oil sounds interesting...

 

[baddad457]

That black "film" that it leaves all over should be enough evidence that it isn't healthy.

I've seen the same black film in automatics too. You know, the ones with 200,000 miles on em ? That film may not look good to you, but it's completely harmless. We're talking about a manual transmission here, not an engine. Not rocket science either. Want to see dirty looking oil ? Go pull the dipstick out of a diesel engine. Even one that's just had the oil changed and run for 10 minutes. They'll go a million miles between rebuilds with that black dirty crap in the oil.

 

[94 lngbd]

I drained my tranny this last weekend in my 94 Ranger to remove tranny & do a completely new clutch job with all new items including new flywheel & slave cylinder. I called the ford dealership to find out exactly which fluid to use cause Schucks/O'Reilly's & Autozones computers dont have done what fluid,just the capacity.

The dealership said there books only go back to 96 & that they show the fluid type to be Mercon V=5 & yes it is a synthetic blend using synthetic & conventional base stocks.

On the bottle of MERCON V is even states that it is also suitable for replacement of DEXRON II,DEXRON III,DEXRON VI,MERCON,MERCON LV,MERCON SP,CHRYSLER 3 & 4,HONDA Z-1,NISSAN MATIC-J,TOYOTA WS,TOYOTA T-IV

 

[exbass94]

On the bottle of MERCON V is even states that it is also suitable for replacement of DEXRON II,DEXRON III,DEXRON VI,MERCON,MERCON LV,MERCON SP,CHRYSLER 3 & 4,HONDA Z-1,NISSAN MATIC-J,TOYOTA WS,TOYOTA T-IV

Just because that particular brand/bottle says it's compatible with all those specs, doesn't mean that all Mercon V fluids are compatible with those specs. Also, I highly doubt that fluid is manufacturer approved for all those specs. It probably says "recommended for....(those specs)" Who "recommends" it? The oil company that made it. NOT Ford, Chrysler, Honda, etc. Unless it says "Ford, Honda, etc licensed and approved" it does not officially meet the spec.