Stupid question: Best fluid for M5OD...and any additives?

[Eddo Rogue]

I am sure there are plenty of old threads, but I figure its ok to ask a stupid question once in awhile.

I have type F in it right now, and I dont think she likes it.
I have a bunch of LV but I heard thats no good either...
There so many types of dex-merc out nowadays...
What should I run?
any additives you can recommend?

 

[Northidahotrailblazer]

In our tech section it says to run Mercon. Thats what i put in mine. I put Type F in my C4, I would think type F would not be right and could cause issues a quick google search says not to use Type F in place of mercon.

 

[Eddo Rogue]

In our tech section it says to run Mercon. Thats what i put in mine. I put Type F in my C4, I would think type F would not be right and could cause issues a quick google search says not to use Type F in place of mercon.

Yea but I am an over thinker, and also dumb. Mercon what? I see many different kinds....Sounds like Merc 3 is what I want.

 

[Eddo Rogue]

The type F was a mistake and has not been in there long.

 

[racsan]

Ive ran pennzoil syncromesh fluid in mine the past several years. No complaints.

 

[sgtsandman]

I think Castrol makes a Dex/Merc as well.

 

[1990RangerinSK]

The best fluid for your transmission is the fluid recommended in your owner's manual.





Ask a stupid question, get a stupid answer.

 

[4x4prepper]

I have run both Dex 3 and syn. gear oil in my various Ford and RBV manual transmissions. I think I am running gear oil in my current B2, but, I would have to double check that.

 

[oldgeek]

The best fluid for your transmission is the fluid recommended in your owner's manual.





Ask a stupid question, get a stupid answer.

I had this question also back when I changed the fluid in mine. I bought my 94 Ranger that had no owner's manual. The downloadable ones start at 95.

I was glad to get the help.

 

[19Walt93]

We used to call the fluid Mercon III but that wasn't right- it was Mercon/Dexron III, if we called our Motorcraft supplier and asked for Mercon III they'd send us the right stuff so I guess we weren't alone in calling it that. Type F isn't as slippery so the syncros might not work right, maybe a little balky about shifting. Motorcraft doesn't sell Mercon/Dexron III anymore but Napa does so I get it from them. If you put synthetic fluid in a T5 it won't shift right- the blocker rings slip too much but I don't know about the M5OD.
I won't buy Pennzoil at any price, they own Jiffy Lube and the concept of Jiffy Lube wouldn't occur to anyone if technicians got 1/10th the respect they deserve. I don't care if the product is any good or not.

 

[Shran]

I have usually ran whatever cheap ATF I had on hand but my thought process has evolved to where I feel that thinner fluids like ATF are good in new or low mileage transmissions and slightly thicker ones like engine oil or Synchromesh MTF may work better in high mileage ones that have looser tolerances from wear. No additives are necessary. "Gear lube" is not appropriate in any of them.

 

[00t444e]

Pennzoil or valvoline Syncromesh is the best fluid to use.

 

[Roert42]

MercV.

I put that shit in everything.

 

[gw33gp]

I am not sure they are right, but Zumbrota says use only non-synthetic ATF in their remanufactured M50D transmissions. They don't indicate which brand to use but have told me if they find synthetic has been use, it would void the warranty. I used Royal Purple Syncromax in my original transmission for 250K miles with no problem and better shifting than what came in it from the factory.

 

[Garth Libre]

This issue is the most contentious and debated issue on the Ford M5OD. I have read use Dextron/Mercon III, Dextron/Mercon V, use either one plus special additives, use Royal Purple, use Mercon with Vatican approved blessings ... etc. I'm at 30,000 miles since my last change, and now I'm more in doubt than ever. I wish the smartest guy in the room would settle this issue.