Mercon Transmission Fluid
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From: Austin, TX
Mercon Transmission Fluid
I just had a 30,000 service done at the local ford dealership, which included an automatic transmission flush and fluid change. When I got the reciept it listed mercon 5 for the new transmission fluid, even though the manual and dipstick say to only use mercon, not mercon 5 or mercon sp. The service manager said that Ford is now recommending mercon 5 because it is a better product, but he didn't have anything (like a TSB) to back this up with. I looked back at several older posts and someone had a link to a FORD website where it specifically says to only use only mercon for my year and transmission type.
I have the 4r100 4 speed automatic transmission in a 2003 v10 2wd. I probably drove about 60 miles with the mercon 5 fluid, and I'm making the dealer put the correct fluid back in tomorrow. Does anyone know if any damage could occur that quickly? Thank you.
I have the 4r100 4 speed automatic transmission in a 2003 v10 2wd. I probably drove about 60 miles with the mercon 5 fluid, and I'm making the dealer put the correct fluid back in tomorrow. Does anyone know if any damage could occur that quickly? Thank you.
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From: USA
Well the latest TSB I have is #01-15-7 it is a tsb that states do not mix mercon 5 with any other type fluid . That includes mercon 3 or mercon.
The reason is that the seals can start to swell and leak and also cause driveability and longevity issues with the tranny.
I would get it in writing that they made a mistake and will repair the tranny in the future if you have issues later on .
This is of course that they don't have a later tsb to back the service guys statement.
Just my $.02
Rich
The reason is that the seals can start to swell and leak and also cause driveability and longevity issues with the tranny.
I would get it in writing that they made a mistake and will repair the tranny in the future if you have issues later on .
This is of course that they don't have a later tsb to back the service guys statement.
Just my $.02
Rich
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From: Lyndonville, Vermont
Yes get everything in writting. also get the TSB in your hands . Don't let them go against your owners manual without taking full responsibility..Maybe he's right but maybe not esp since we didn't hear about it here.. Let us know
Dick
Dick
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The service manager is partially correct, Ford did recommend switching some transmissions over to Mercon V to help with torque convertor shudders, however this does NOT include the Superdutys. I did a lot of searching on this topic a few months ago and the concusses seemed to be that Mercon V is not good for this model transmission. Do a search on this forum, if I remember correctly someone else had the same problem with a dealer. When he confronted them they towed it back to the dealer and changed the fluid back to Mercon.
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I did see that post. They're going to change it back in the morning, although I think the dealer still thinks he did the right thing. He said he's been using the mercon 5 for the last several years in the 4r100. I hope there hasn't been any damage. I'm going to try to get them to extend the warranty on the transmission. Thanks for all the replies.
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From: colorado
Originally Posted by ford390gashog
mercon 5 will destroy a 4r100 transmission.
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I was told by my dealer to use Mercon V. Three guys behind the counter said to go ahead and use V. I called another and he said NOT to use V and that in fact the XT-2-QDX is Mercon III. I am so confused. I also can NOT find straight MERCON and most of the fluids have multiple spec suchs as Mercon/Mercon V or Mercon/Mercon III.
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There is no such thing as MERCON III. There is DEXRON III/MERCON, and that's what the 4R100 uses. DEXRON III and MERCON are just about identical, so one fluid meets both specs. Don't use MERCON V or any fluid that has both MERCON and MERCON V.
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From: Austin, TX
I found this link from an older post. It was very helpful. When I showed it to the dealer, he was speechless.
http://www.fcsdchemicalsandlubricant...ickref-atf.pdf
http://www.fcsdchemicalsandlubricant...ickref-atf.pdf
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From: Austin, TX
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Back in December of last year, I had my 30K service at the dealer. They did a complete flush and drain. They filled with 12 qts of MERCON V. I have put 22K since then and had ZERO issues. Until this tread, I never realized they used anything different than what they were supposed to.
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From: Farms of Duplin County
Originally Posted by boxcar1974
Back in December of last year, I had my 30K service at the dealer. They did a complete flush and drain. They filled with 12 qts of MERCON V. I have put 22K since then and had ZERO issues. Until this tread, I never realized they used anything different than what they were supposed to.
I've got an 01 V-10.
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Originally Posted by Casey
There is no such thing as MERCON III. There is DEXRON III/MERCON, and that's what the 4R100 uses. DEXRON III and MERCON are just about identical, so one fluid meets both specs. Don't use MERCON V or any fluid that has both MERCON and MERCON V.
oops
On the flip side with the PDF listed above, it clearly states,
"Use of a transmission fluid that indicates dual usage (MERCON®, MERCON® SP OR MERCON® V) in an automatic transmission application requiring MERCON® may cause transmission damage. Use of any fluid other then the recommended fluid may cause transmission damage."
Does this mean MERCON and DEXRON III designations as well since I guess it is a dual usage? I don't see anywhere in the PDF of any mention of Dexron III.
EDIT: I did a little research just now. I am not a mechanic which is why I did not know this but DEXRON III is a GM (chevrolet) specification whereas Mercon is the Ford spec. I couldn't find straight MERCON. I thought Dexron III/Mercon was a dual usage fluid for Ford. This is why I steered away due to the PDF listing of "Use of a transmission fluid that indicates dual usage (MERCON®, MERCON® SP OR MERCON® V) in an automatic ransmission application requiring MERCON® may cause transmission damage." where I read in this website elsewhere as well.
Last edited by Richard4447; Nov 12, 2005 at 07:41 PM.
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I had the dealer put the mercon (now called mercon 3) back into my transmission today. The part number on the mecon 3 quart was the same one listed on the PDF for regular mercon. It might be my imagination, but the shifts feel a little better (firmer) now than when I was running on mercon 5.