Quick help with tranny fluid

[fr7]

Hi again, I'm changing transmission fluid, 98 ranger 5 speed, I did the transfer case a little bit ago and I assume the tranny takes mercon V too, am I right? The guy at AutoZone told me it takes 10+ quarts and I know he's full of shit, about how much does it take before it starts coming out of the fill plug???

 

[Pauls 4x4]

Five speed takes gear oil not atf (automatic transmission fluid). Should be 75-90 or something. Now, with that you do pump it till full and call it a day.

 

[fr7]

Are you sure about that? Because every place I've called said it takes mercon V, I don't want to put the wrong stuff in it.. I have mercon V in the transfer case..

 

[Spott]

I don't know the specifics of the 98, but as an example, my 88 has a BW 1350 transfer case that uses ATF (Dex III/Merc, IIRC) and a Mitsubishi FM146 5-sp transmission that takes 90W gear oil (I use 80-90W bargain brand oil).

Have you tried looking up the specs in the owners manual or service manual? That would be the authoritative source.

10 quarts is also an awful lot, mine takes 5-6 pints (2.5-3 quarts). Again, the service manual will list the fluid capacities you need.

 

[Curious Hound]

Have you tried looking up the specs in the owners manual or service manual?

Is that the funny little book I threw out so there would be more room for condoms in the glove box?

 

[4x4junkie]

Are you sure about that? Because every place I've called said it takes mercon V, I don't want to put the wrong stuff in it.. I have mercon V in the transfer case..

'98 M5OD takes Mercon (not Mercon V).

However Ford (in cahoots with GM regarding Dexron III too) pulled the licensing of these names around 2007 or so, so now the correct fluid is called "Dex/Merc" by most brands. This is what you want to use.

In my experience, Mercon V causes hard shifting in manual transmissions, my guess is because it's additives are too slippery for the synchros to function correctly (and is likely why companies continue producing the Mercon fluid as Dex/Merc).
Initially Ford said Mercon V was NOT compatible with applications calling for Mercon, then for whatever nonsensical reason they changed their mind on it. They should've just stuck with their original advice. Maybe Merc-V is fine in automatics calling for Mercon, but I will never use it again in a manual.

×2, the M5OD takes right around 2.75 quarts.

Mercon V should not cause any issues in your T-case however (no synchros in the t-case).


Edit:
It just occurred to me the '98 automatic is a 5-speed also, so maybe some clarification is in order since everyone (me included) assumed "5-speed" meant the stickshift. The 5R55E automatic actually does call out for Mercon V fluid.

 

[fr7]

Sorry for the confusion. Yes, I refer to a stick shift as a 5 speed, sometimes as 5 speed manual, I don't know why, it's just what I always hear people around me call it lol. Does newer ford rangers have a 5 speed automatic or just 4? I've only owned 1 automatic car in my life, its a Roadmaster wagon, it runs but it's wrecked..

 

[4x4junkie]

The Ranger & Explorer (4.0L engines) both got 5-speed automatics for '97. I believe that same 5-speed auto carried through all the way to the Ranger's demise after 2011.

Before the early-mid '90s, automatics with more than 4 speeds were almost unheard of, so an easy way to distinguish was to say you had a "5-speed" (referring to the manual, which during this same period ('80-'90s) almost invariably had 5 gears (+ reverse). Today most manuals are six-speed, and most autos have 6 - 9 speeds (would hate to see the bill to rebuild one of those lol).

 

[jonathan62019]

I put mercon V in mine and it shifts better. Walmart has a super tech red bottle says high mileage formula. It was over a dollar cheaper than the cheapest mercon V i could find.

 

[black_demon69]

ok
i was told by a transmission guy that has been rebuilding transmissions for around 40 years that the m5odr1 would be fine with anything from atf to 30 weight motor oil but no heavier then 30 weight.. with that being said i run dex/merc atf with 1/3 lucas oil treatment in mine and it shifts very smooth. all be it my m5od was rebuild recently and works like new...

what do you all think?

 

[jonathan62019]

should be ok. it uses atf fluid because it is what we call splash lubed gear box. if oil is too thick it will not splash on to everything and some gear will burn up. so no thick crap in them