M5OD Alternative Fluids

[97Ranger3.0]

*Let me start this off by saying, yes I know that the M5OD takes Mercon V ATF, and that you should go with what is recommended by the vehicle manufacturer
*I'm not condoning using the incorrect transmission fluid, I would just like this to be a discussion on what people have tried and their results
*Please don't reply to this thread if you're just going to say to use Mercon V because Ford says so, unless you have an argument to back it up as to why Mercon V is superior to all other fluids in this case; other than just because Ford says you should use it.


With that said, I stumbled across a post in a forum here recently where someone said they switched their transmission fluid out in their M5OD from ATF to 0w-30 full synthetic engine oil and they claimed that it helped with noise and shifting issues. It got me wondering what other fluids may actually be more suitable in a manual transmission such as the M5OD than an ATF? Like syncromesh, GL4 gear oil, engine oil... etc. I've even heard of a few people putting automatic transmission stop slip additives in manuals with positive results. One guy even said his local transmission shop claimed that all manuals should use 0w-30 engine oil, and because of this he has used 0w-30 in the transmissions in their manual cars with no issues. After doing some research, it just got me wondering... is ATF really the best fluid for a manual transmission?

I think it would be cool to have a discussion for people to input their experience with using different fluids in the M5OD.

 

[Dirtman]

I think a major concern with using gear/motor oil is sulphur content. Alot of gear/motor oils use sulphur which is a great wear additive, but sulphur destroys bronze which is used in the m5od. Now Ford could spec a specific grade and type of sulphur free oil BUT it's probably safer for ford to just spec something that never has any sulphur in it, aka Mercon/Mercon V to avoid mixups and exploding transmissions. Is Mercon the best fluid for the job? Dunno, but its probably the safest from that standpoint. I could definitely see a higher viscosity oil helping a bit with slop and noise on an older transmission as Mercon is a very low viscosity.

 

[adsm08]

I think a major concern with using gear/motor oil is sulphur content. Alot of gear/motor oils use sulphur which is a great wear additive, but sulphur destroys bronze which is used in the m5od. Now Ford could spec a specific grade and type of sulphur free oil BUT it's probably safer for ford to just spec something that never has any sulphur in it, aka Mercon/Mercon V to avoid mixups and exploding transmissions. Is Mercon the best fluid for the job? Dunno, but its probably the safest from that standpoint. I could definitely see a higher viscosity oil helping a bit with slop and noise on an older transmission as Mercon is a very low viscosity.

Gear oil also does not make it's way into the pocket bearing between the two halfs of the main shaft. Even with thin ATF that bearing barely gets enough lubrication.

I have heard Redline is good stuff.

 

[racsan]

I use something called “pennzoil syncromesh fluid” was about $7 a qt the last I knew of. One time I used 303 tractor hydraulic oil, had a transmission that was low on oil & had wrong oil in it, thought I had atf on hand but didnt , so I used what I did have. Ran it a week or two with no issues then drained & refilled with the pennzoil syncromesh fluid, that was 3 years ago. Hasnt gave me any problems.

 

[franklin2]

It gets too cold in Mass. to use anything but ATF. I have tried several different types of oil in a 5 speed zf. All to try and minimize noise at idle from using a solid flywheel on a diesel. Different trans, but I can relate the results of that experiment.

It was said to use straight 30w oil and overfill the trans. It did help with the noise some, but when it got below 30 F I could hardly shift the trans going down the road until it warmed up.

I tried 10w-30. It was better, but still hard to shift when it got really cold.

I finally went back to straight dexron III. Shifts fine now in any type of weather. Noise is almost gone since I raised the idle speed up a little bit.

 

[gw33gp]

I have been running Royal Purple Synchromax for the last 150K or so miles. Just before the transmission had 250K miles on it I had it taken apart to make sure I would not have any issues with it. They did replace the 5th/reverse cluster because it was worn a little. Everything else was in good condition, but I asked to have the bearings replaced as well as the seals so it would be in the best condition possible.

I get smoother shifts with Synchromax compared to ATF, especially when cold. I can't say it is better for wear than ATF for the transmission, but it certainly is not worse for it with the condition of the transmission at near 250K miles.

Honestly, I am not sure the 5th/reverse cluster needed to be replaced. It was not giving me any problems and they gave me the old cluster and I could not see anything wrong with it.

 

[97Ranger3.0]

Dirtman - I'd be curious to know the sulphur content in a synthetic engine oil, and if it would be enough to cause a concern. Isn't it the sulphur content of GL5 gear oil that makes it not suitable for a lot of modern manuals, and that's why GL4 gear oil is used instead?

racsan - Thanks for the input about syncromesh, I've been curious about that vs ATF in a manual like the M5OD

franklin2 - That does make sense, but I wonder if going with a 0w-20 or 0w-30 instead of 10w-30 would help with that cold shifting issue.

gw33gp - I think I might actually try that RP Synchromax next time I change my trans fluid. It's probably the safest thing to try switching to from ATF. I'm curious if that would help with some noise and shifting issues I have as well!

 

[Dirtman]

What am I a scientist lol. My point about the use of gear oil is that say ford specs 80w90 GL4. How many people actually check the rating of the oil beyond just 80w90? Even the dealer could screw that up. I just think it's safer from a warranty standpoint on fords end to just flat out avoid the possibility of a mixup.

As for motor oils, im fairly certain they all contain some sulphur. How much? And how much is enough to be damaging to the transmission? I do not know. I have some of my blackstone oil analysis sheets somewhere that show the sulphur content, when I find one Ill post it.

 

[19Walt93]

In the 70's Ford had a TSB advising 10w40 synthetic motor oil for use in New Process 435 creeper gear 4 speeds to make shifting them easier in sub zero weather. Throught the 60's and 70's when everyone else used 80-90, Mopar filled their standard transmissions with ATF and it worked fine, I didn't see anything different in their transmissions compared to Ford and GM units of the day. Warner T5's always used Mercon and I've heard that synthetic ATF causes them to have shifting problems because it's so slippery the locker rings can't grab If you try alternative fluid and don't like the way it works, drain it out.

 

[racsan]

Dads ‘74 F250 was a bear to shift below 20 degrees, I never knew about that tip. What a transmission though! If all 4 of us were in the truck, youd better watch where your knee was when dad went for reverse, he didnt wait for you to move a leg. Learned quick on that one!

 

[Shran]

I'm a little skeptical that engine oil would have enough additives to react with bronze... some engines have bronze internal parts, I'm thinking distributor drive gears and such.

I have had some success using synthetic 5w-30 oil in one transmission. It cleared up a 1->2 shift grind on a high mileage trans and I never saw any ill effects from it. I've tried it several other times and it either did nothing or caused some crunchy shifting, went back to ATF in those cases and all was well.

I need to experiment with engine oil in my NP435 too now that y'all mentioned it. That thing doesn't shift smooth no matter what the ambient temp is until I've driven it for a while.

 

[97Ranger3.0]

Dirtman - I understand - I wasn't trying to argue with you or anything so I hope it didn't come off that way, just contributing my thoughts on the topic. I definitely understand what you're saying and that would be an easy mixup. In all honesty I didn't know what the difference between GL4 and GL5 gear oil was until recently. I can only imagine the average person who doesn't know the difference going to an auto parts store and asking for the correct fluid for their transmission and being sold the wrong stuff by the dope who works at the front who probably knows even less . So in that respect I do understand spec'ing an ATF because it should make that easier (although I'm sure people still get the wrong stuff often lol). If you do find your analysis sheets, definitely share them here!

Shran - That's a good point about some engines having bronze internal parts.

Man, all of these replies are making me just want to go for it and try different fluids. If I don't like it, just drain it out as someone previously said. Maybe one day if I plan to replace or rebuild this transmission I'll just try some of these before swapping it out.

 

[RobbieD]

For what it's worth, I'm trying Amalie synthetic ATF in my M5OD since I did the clutch, about a year and just over 3,000 miles ago. No problems so far, and it did really smooth up the shifting. The local parts store suggested it to me, and I looked around the net and found good reviews, no red flags.
So I gave it a shot and like it so far (be prepared if you try it- it smells terrible!).

Anybody else run this stuff?

Not really a recommendation; I'm trying it and like it. This is it on their website:
http://www.amalie.com/Universal-Synthetic-Automatic-Transmission-Fluids/Universal-Synthetic-Automatic-Transmission-Fluid/products/files//35B4BECBF7C5/Rev_Amalie_SYN_ATF_Spec_Sheet.pdf

 

[85_Ranger4x4]

When I I was researching a few years ago the vibe I got was not to use Mercon V in manual transmissions.

I have the Penzoil Syncro stuff in mine, it seems happy.

 

[Dirtman]

Go away.