Front differential leaking, safe to drive in 2WD mode with front hubs unlocked?

[Dirtman]

thanks for the information. My transfer case has a manual selector lever next to the manual 5spd shifter. I take it its not a shift on the fly unit ?

Doesn't mean it's not shift on the fly. Pretty sure all rangers were shift on the fly. (Someone can verify this). Electric or manual shift didnt matter, all that means is you could shift into 4wd high up to 30 or so mph. To go to low you have to stop and go into neutral.

 

[SenorNoob]

I'm not aware of any factory Ranger transfer case that wasn't "Shift on the Fly". Even the old 1350 was called such in the owner's manual.

I wonder why Mercon V shouldn't be used in them though?

I know at some point the fluid changed to be more corrosive to brass parts. Maybe it's related?

 

[Dirtman]

I'm not aware of any factory Ranger transfer case that wasn't "Shift on the Fly". Even the old 1350 was called such in the owner's manual.

I wonder why Mercon V shouldn't be used in them though?

I know at some point the fluid changed to be more corrosive to brass parts. Maybe it's related?

Nope there's plenty of brass in an M5OD and mercon V works great in them. I tried digging and basically what I found was a few transfer cases serviced by dealers exploded after Ford dropped Mercon from their products and only used Mercon V as the replacement. No one has an actual answer why but shortly afterwards Ford rescinded their recommendation to use Mercon V to replace Mercon in transfer cases and starting selling "transfer case fluid" which is literally just rebadged Mercon. Some say it was an issue with Mercon V being too slick and causing parts to slip that was the problem but that seems unlikely since it still works great in manual transmissions. Some people say it was a conspiracy and that it was really lizard people who blew up those transfer cases.

 

[SenorNoob]

Damn lizard people.

 

[Blmpkn]

Personally, I think the crab people are just as big of a nuisance.

 

[dirtymike]

Is this a dealer item only? Dirty

 

[Dirtman]

Is this a dealer item only? Dirty

If you're referring to "transfer case fluid" then no. It's motorcraft so it's available anywhere motorcraft stuff is sold but just because Ford stopped making Mercon doesn't mean other companies have. You can still buy Mercon in various brands like Valvoline, Mobil, etc.

 

[dirtymike]

I'm changing fluids soon in the ranger and 8N tractor and want to get one order for everything, so mercon in the T-Case is good? Thanks Dirty

 

[Dirtman]

I'm changing fluids soon in the ranger and 8N tractor and want to get one order for everything, so mercon in the T-Case is good? Thanks Dirty

Yes, if that was what was originally in it, and that's what the manual recommends then that's what should still be used. Anything else (manual trans, auto trans, and power steering) that once called for Mercon can happily use Mercon V.

Just double check it's not one of the older transfer cases that takes gear oil.

 

[4x4junkie]

Mercon V is indeed the direct replacement for Mercon in automatic, manuals,, and power steering... everything EXCEPT transfer cases. Ford sells a specific transfer case fluid now which is just rebadged Mercon. Mercon V is a better fluid all around but doesn't work right with older shift on the fly transfer cases for some reason. Pretty sure it even says that on the back of the Ford Mercon V bottle.

View attachment 63666

Indeed it is because it's additives are too slippery for the electromagnetic spin-up clutch to spin the front driveshaft up to speed properly. If it takes too long to spin up before the shift happens, the difference in speed between the t-case itself and the front driveshaft causes the shift gear to clash and that can potentially lead to the subsequent case explosion.

For this same reason I never recommend it's use in manual transmissions either unless specifically called for; it's slipperiness is often too much for the synchros to function and can cause hard shifting in the M5OD as well (already been there, done that)

For sure, use only "Dex/Merc" fluid in the M5OD, as it matches the original Mercon spec the (pre-2008) M5OD trans and t-case call for. Dex/Merc fluid is usually much cheaper than the so-called Transfer Case Fluid too.



Merc V should be OK in a NON-shift-on-the-fly t-case (or if you have a 2000 or newer truck WITHOUT locking hubs of any type on the front axle), as neither will have the spin-up clutch in question... But my personal opinion: Merc V has no business whatsoever in any part of a Ranger unless it specifically calls for it (such as if it has a (x)R44E or (x)R55E automatic or is 2008 or newer).

 

[fixizin]

Seriously though, if I have some UNopened, Advanced Auto brand Dex/Merc ATF from Duh Year 2000... would that be GTG??