MercV in transfer cases -- why not?

[D60]

FTM (Ford Tech Makuloco) has at least two vids saying MercV will make a t-case explode. One video is an AWD cute ute, and I get that.

But there's a second video claiming the same thing about what he calls "chain and sprocket" t-cases -- I call them part-time, driver selectable, but potato/potahtoe

I'm not suggesting this information is wrong, but I'd love to know WHY. As mechanics and technicians, the more we understand about the inner workings of a given issue, the better we are at our trade -- and I'd argue at life in general.

It is true even the MercV bottles say not to use in transfer cases. That's great, but it's not a reason.

The best --er only-- reason I found on the interweb was that MercV does not provide adequate protection for yellow metals. Hmm, ok....maybe. I think there may be some yellow metal bushings or bearings in some driver selectable, part-time t-cases? Perhaps in the synchro (where applicable) or maybe in the planetary assy?

But in order for the yellow metal argument to make sense to me, there would have to be no yellow metals in Ford transmissions like the 4R70 -- and I honestly don't know if there are? @clinebarger any thoughts?

Furthermore, apparently, the M5OD was supposed to run MercV once Merc was discontinued. I'm not sure about the 5sp ZF found in OBS Fords 3/4t+ ? Do either of these manual transmissions have yellow metals?

I'm open to input, and I'm simply trying to understand the WHY. I don't believe I'm right or wrong --I don't have a conclusion YET --, I just feel I'm lacking information.

Is anyone aware of something that MercV has or is lacking that would cause a basic part-time, driver selectable t-case to die an early death but survive with original Dex/Merc or MercLV?

@bdcardinal any thoughts?

 

[bdcardinal]

No clue as to the real reason. I sell what the manual says to use on the application. Which reminds me, I still need to change the t-case fluid in my F-350.

 

[Kira]

^^And the fluid you'll use is Mercon-LV, yes?

I've no knowledge of yellow metal parts within Ford units either but I do recall a 'blanket' backpeccing to LV in ALL transfer cases not that long ago (3-5years?), IIRC.

I used Valvoline MaxLife Dex-Marc LV in my Ranger. Shifts smartly and consistently.

 

[SwampSurvivor]

FordTechMakuloko is mostly a sham who got fired from a Ford dealer for publicly making so many videos trashing Ford products.

For your standard chain-drive transfer case, there's nothing different between Mercon and Merc V.

The power steering, ZF 5 speed transmission and NP 271 transfer case in my F-350 call for Mercon V fluid. I've been in a lot of the NP transfer cases and as long as they have a lightweight fluid in them they are happy.

 

[ripcord]

The completely unsubstantiated reason (by me at least) that I've read online was that there was something in Mercon V that attacked the adhesive used in SOME transfer cases so the clutch material de-laminates. Whether or not this is true, I have no idea. Not all transfer cases have clutches, so if this was the true reason, then it would stand to reason that Mercon V would be fine in T-cases without clutches.

No proof, and this could be completely bogus.

 

[burbguy82]

I would think that MerconV and Dexron would be just as good in either makers t-case.......Maxlife for instance meets both specs, and there is really nothing special going on inside a tcase.........not really.......unless MerconV just "sucks"......interesting topic.

 

[SwampSurvivor]

I would think that MerconV and Dexron would be just as good in either makers t-case.......Maxlife for instance meets both specs, and there is really nothing special going on inside a tcase.........not really.......unless MerconV just "sucks"......interesting topic.

Mercon V is only special because it contains the additives to prevent torque converter shudder. Otherwise it's no different than Dex II / Merc

 

[4WD]

I have had my fair share of transfer cases that called for Synchromesh, Dexron VI, 75W140, and ATF+4. Those are very different fluids - so I never strayed from the owners manual and never had any issues with any of them ...

 

[burbguy82]

Mercon V is only special because it contains the additives to prevent torque converter shudder. Otherwise it's no different than Dex II / Merc

I am sure there is a difference of some kind, but not enough to matter so much in a tcase......is what I was saying..

 

[clinebarger]

But in order for the yellow metal argument to make sense to me, there would have to be no yellow metals in Ford transmissions like the 4R70 -- and I honestly don't know if there are? @clinebarger any thoughts?

The 4R70 has plenty of yellow metal in the form of Bushings & Thrust Washers.

 

[clinebarger]

The completely unsubstantiated reason (by me at least) that I've read online was that there was something in Mercon V that attacked the adhesive used in SOME transfer cases so the clutch material de-laminates. Whether or not this is true, I have no idea. Not all transfer cases have clutches, so if this was the true reason, then it would stand to reason that Mercon V would be fine in T-cases without clutches.

No proof, and this could be completely bogus.

Doesn't sound right....Clutch Plate manufacturers all use the same process to bond friction material to a steel core.

 

[SwampSurvivor]

I am sure there is a difference of some kind, but not enough to matter so much in a tcase......is what I was saying..

Oh for sure - agreed!

 

[BISCUT]

^^And the fluid you'll use is Mercon-LV, yes?

I've no knowledge of yellow metal parts within Ford units either but I do recall a 'blanket' backpeccing to LV in ALL transfer cases not that long ago (3-5years?), IIRC.

I used Valvoline MaxLife Dex-Marc LV in my Ranger. Shifts smartly and consistently.

I believe you are correct, Sir. First time I did a trans pan dump on my 15 F150 6R80 I remember my Indy telling me LV in the transfer case as well and not to use Mercon V in this unit.

 

[thastinger]

My 98 F150 tranny and t-case originally called for "Mercon" which is obvi not sold any longer so I just get the jugs of dex/merc from wallyworld. There was a time when people would say you couldn't use Dex in something that called for Mercon but not both names are on the same bottle.

I still don't understand how the universal max life fluid can meet so many specs across the conventional and synthetic range(like all of the Nissan Matic specs it meets)

 

[D60]

I'm going to order MercV from RA for my '07 F150 and put it in the t-case.

The problem with my "experiment" is that it will prove nothing. If the case is happy, it's a sample of one. If the case explodes, it's likely got 240k freedom units on it so difficult to say what caused death (although an autopsy might provide a couple clues).

I was just disappointed that FTM was indignant that I dare question the bottle. As I said, I like to know the WHY regardless of whether I agree with a statement or am skeptical of a statement.

I think we're all put on this Earth to learn at least one new thing a day and one of the best tools to do that is ask questions

 

[D60]

Doesn't sound right....Clutch Plate manufacturers all use the same process to bond friction material to a steel core.

I wondered about this too. And often when you order aftermarket rebuild kits for Auto t-cases I'm told the frictions they furnish are just auto trans clutches -- specifically, this is what I was told about GMT800 NP246 kits

 

[burbguy82]

I'm going to order MercV from RA for my '07 F150 and put it in the t-case.

The problem with my "experiment" is that it will prove nothing. If the case is happy, it's a sample of one. If the case explodes, it's likely got 240k freedom units on it so difficult to say what caused death (although an autopsy might provide a couple clues).

I was just disappointed that FTM was indignant that I dare question the bottle. As I said, I like to know the WHY regardless of whether I agree with a statement or am skeptical of a statement.

I think we're all put on this Earth to learn at least one new thing a day and one of the best tools to do that is ask questions

I agree, no real measurable result either way. If I were you, I would just use the Ford juice. Even though Ford sucks.

 

[burbguy82]

Doesn't sound right....Clutch Plate manufacturers all use the same process to bond friction material to a steel core.

I was watcing a video on YT with Precision Transmission, there in TX. The video was about the NP246, and in the video he issuarated the clutch packs in the NP246, were the exact same as in a Dodge auto transmission. This substantiates your statement. One uses ATF+4, and the other dexron.

I wonder if the fluid difference has more to do with something other than the clutches.......it would seem so.....or in other words it might have nothing to do specifically with the clutches and what fluyid they use

 

[ripcord]

I wondered about this too. And often when you order aftermarket rebuild kits for Auto t-cases I'm told the frictions they furnish are just auto trans clutches -- specifically, this is what I was told about GMT800 NP246 kits

In that case, the only other difference between Mercon and Mercon V that would be relevant would be the friction modifiers. Maybe Mercon V will allow the clutches to slip more in that application?

 

[D60]

In that case, the only other difference between Mercon and Mercon V that would be relevant would be the friction modifiers. Maybe Mercon V will allow the clutches to slip more in that application?

Maybe.

In contrast GM's Auto cases are supposed to get AutoTrak II because it allegedly contains friction modifiers. Supposedly if you use straight Dex/Merc (or DexVI) you get what is essentially chatter because the clutches can't modulate.