Mercon V replacement for Mercon in Transfer Case?

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2004 F-150 4.6L 4x4 I was thinking about changing the transfer case fluid in my truck and was get conflicting information on what fluid should go in. The owners manual says to use Mercon so I was going to go ahead and use Mercon V. I got to looking around on the Motorcraft site and found where it says (in regards to Mercon V): "Do not use in applications where MERCON® SP, MERCON® LV, Continuously Variable Chain Type Transmission Fluid, Motorcraft® Premium Automatic Transmission Fluid, FNR5 Automatic Transmission Fluid or Type F Automatic Transmission Fluid is recommended, or in transfer cases." I am reading this as to not use Mercon V in transfer cases, but the dealer I just spoke with said that Mercon V superceded all applications of Mercon - including transfer cases. Also, Ford has issued individual TSB's regarding Mercon V superceding Mercon in manual and automatic transmissions and power steering units - but I can't find one relating to transfer cases. The truck only has 42,xxx miles on it so I am in no hurry to get it changed - I just bought the truck a few months ago and wanted to get all the fluids replaced. What fluid does BITOG think should go in this transfer case? Is Mercon V just an upgrade to Mercon or are there physical changes (friction modifiers, viscosity differences) What fluid comes in this unit from the factory? Thanks
 
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Since Mercon V is better than Mercon (not to mention that you can't get Mercon) I don't see why it can't be used. However, you only need 1.5 quarts, so why not use M1 AFT, or Amsoil ATF?
 
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Thats because friction modifiers can cause slippage which would be bad in the 4r100 that is being worked. If the xfer case is mechanical, its shouldn't care about anti-shudder durability. Because a transfer case is usually under maintained, under sump'd, and some can be overworked and overheated easily, I would use a full synthetic ATF. In hotter climates, something thicker along the lines of a racing ATF or mtf/mtl could be considered. The x-12 is equivalent to the original mineral Mercon ATF. XT-2-QSM Mercon synthetic is the only fluid I would use from the stealership.
 

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 Originally Posted By: unDummy
Thats because friction modifiers can cause slippage which would be bad in the 4r100 that is being worked. If the xfer case is mechanical, its shouldn't care about anti-shudder durability. Because a transfer case is usually under maintained, under sump'd, and some can be overworked and overheated easily, I would use a full synthetic ATF. In hotter climates, something thicker along the lines of a racing ATF or mtf/mtl could be considered. The x-12 is equivalent to the original mineral Mercon ATF. XT-2-QSM Mercon synthetic is the only fluid I would use from the stealership.
Exactly. That's why I said "better" is relative.
 
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Forgive me...I should have stated MEC V is better that MEC in this application given it is made out of better base stock, ect, ect ect...Yes, it's all relative, but in this case it's better
 
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XJ1100

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It sounds like a good universal synthetic ATF (that meets Mercon/Mercon V) would be the best option. What is the consensus on Schaeffer's #204 All-Trans Supreme Automatic Transmission Fluid? How about this fluid in the automatic transmission as a Mercon V fluid?
 
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 Originally Posted By: OVERK1LL
"better" is relative. It sure isn't "better" for the 4R100.....
According to Ford the 4R100 can now be serviced with Mercon V certified fluid. Here is the TSB: A/T - Mercon V ATF Usage TSB 07/24/06 MERCON ATF IS BEING REPLACED BY MERCON V ATF AS A SERVICE FLUID. FORD: 1980-1997 Crown Victoria 1981-1997 Mustang, Thunderbird 1981-2003 Escort 1986-1993 Festiva 1986-1997 Taurus 1989-1997 Probe 1994-1997 Aspire 1995-2000 Contour 1980-1996 Bronco 1981-2003 F-150 1981-2004 E-Series, F-Super Duty 1983-1996 Ranger 1986-1996 Aerostar 1991-1997 Explorer 1993-2004 F-53 Motorhome Chassis 1995-1998 Windstar 1997-2004 Expedition 2000-2005 Excursion 2001-2007 Escape 1987-2000 F-B-Series 2000-2007 F-650, F-750 LINCOLN: 1980-1997 Town Car 1981-1997 Continental 1993-1997 Mark VIII 1998-2004 Navigator 2002-2003 Blackwood MERCURY: 1980-1997 Grand Marquis 1981-1997 Cougar 1986-1997 Sable 1987-1999 Tracer 1995-2000 Mystique 1999-2002 Cougar 1993-2002 Villager 1997 Mountaineer 2005-2007 Mariner MERKUR: 1985-1989 XR4TI This article supersedes TSB 01-15-7 to update the vehicle application chart. ISSUE MERCON(R) Automatic Transmission Fluid is being replaced by MERCON(R) V as a service fluid. ACTION Beginning immediately all automatic transmission / transaxle applications requiring MERCON(R) can now be serviced using MERCON(R) V or MERCON(R) Automatic Transmission Fluid or dual usage fluids labeled MERCON(R) / MERCON(R) V. After July 1, 2007, MERCON(R) Automatic Transmission Fluid will no longer be manufactured, therefore, availability of this fluid will only continue for however long it takes to deplete what remains in inventory. SERVICE PROCEDURE Service automatic transmissions requiring MERCON(R) with MERCON(R) V or MERCON(R) Automatic Transmission Fluid or dual usage fluids labeled MERCON(R) / MERCON(R) V As for universal atf's, our 4R100 had a dramatic improvement in shift quality when it was switched to AMSOIL ATF. Shifts are smoother, no more torque converter shudder during lockup, and nice firm shifts on heavy throttle. I have also used the Schaeffer #204 in Mercon V applications with good results, I would be happy running either one.
 

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There is ANOTHER TSB from Ford noting not to use Mercon V in the 4R100. It apparently kills them in relatively short-order.
 
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This thread is a transfer case thread. Who cares about the 4r100?! The Schaeffers is an excellent choice.
 
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I drained and refilled the transfer case in my 2002 4WD V6 4.0L Ford Explorer at 60,000 miles with Mobil 1 Synthetic ATF. Works like a charm. I would choose any good quality ATF for a tcase to replace the Mercon that was the factory fill. The tcase does have a magnetically activated, ball driven clutch in it, but it works well with the Mobil 1 ATF I put in and I suspect it will work with just about any ATF that covers Mercon or Mercon V uses. I would have put Schaeffer's ALL-Tran synthetic ATF in, but all 12 Quarts I purchased was used in my automatic transmission. Rumple
 

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 Originally Posted By: unDummy
This thread is a transfer case thread. Who cares about the 4r100?! The Schaeffers is an excellent choice.
Because the Mercon/Mercon V application guide is still somewhat vague and has a lot of people confused. Many seem to think (even some dealers) that you can put Mercon V in anything that previously spec'd Mercon, and that is not the case.
 

XJ1100

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I filled it up with 2 quarts of Schaeffer's All-Trans Supreme this past weekend. I am sure this will be a great fluid for my application. If Ford is going come with a new transmission fluid they should make it supercede ALL applications of the original fluid. It sounds like the Schaeffer's would also do well in my transmission.
 

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 Originally Posted By: Bluestream
 Originally Posted By: OVERK1LL
 Originally Posted By: Rob_Roy
I would be interested in reading it, do you have the TSB #?
Here ya go, even shows an application graph: http://www.thedieselstop.com/faq/9497faq/tsb/tsb/01-15-07.php3
Overkill, this is a very old chart from 2002. They have changed the recomendation since then
I know the chart has been updated, but there are still many (albeit, in the diesel community) including many from Ford that state that Mercon V is damaging to the 4R100. This may only apply to HD apps, but is something to consider.
 
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 Originally Posted By: OVERK1LL
I know the chart has been updated, but there are still many (albeit, in the diesel community) including many from Ford that state that Mercon V is damaging to the 4R100. This may only apply to HD apps, but is something to consider.
um no, its not something to consider. that has been superseded. if you go to the real FSM, its not even there anymore as it is old information.
 
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