Mercon vs MerconV

[blueglide88]

My '99 Sable syas use MerconV on the dipstick. My manuel says Mercon. Whats the difference? Also, where can I find info on the quality of atf's? I poumped out what I could, and poured in dexron/mercon from Murrays Auto. I did this 2 weekends in a row, I'm trying to flush out the old. Is Murrays any good? Is it the same as all other trans fluids? I'm just too lazy to drop the pan and disconnect the lines. I'm trying to solve a intermitent slipping problem. It happens only when hot, and Sables/Taurusus are known for weak trannies. Its been doing it for 2 yrs, and I'm trying to get all I can before I spend on a new trans.

 

[RF Overlord]

blueglide:

Your '99 Sable uses Mercon V...if you've put Dexron III/Mercon in there, you really need to do a proper flush and get it all out of there, or you WILL have problems. The Taurus/Sable transaxle is not known for being super-rugged, and feeding it the wrong ATF will not do it any good at all.

 

[TooSlick]

Mercon and Mercon V fluids have the same frictional properties for clutch materials. However, Mercon V requires better high temp stability and better pumping in cold temps. In addition, Mercon V requires several tests to evaluate gear protection, including the Falex Test, The Four Ball Wear Test and the FGZ gear test.

Mercon V is the superior fluid and should not be substituted w/ Mercon.

TS
Dixie Synthetics

 

[Big Jim]

In many cases Mercon V and Mercon should not be interchanged. Upgrading to Mercon V is a strict no no on the auto trans used in the Ford Escape and Ford Contour. Evidently some seals may not be compatable with Mercon V.

The above post was correct on the differences. As it was explained to me, the main difference is the the viscosity index is higher on Mercon V, meaning that it is somewhat like a multi viscosity engine oil except it is for your trans.

 

[Marlin]

^

You have alink to back that up? As Exxon/Mobils Ammco ATF MerconV says it can be used in older trans and current ones that call for Dex3/Mercon fluid

 

[medic]

quote:

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Originally posted by Marlin:
^

You have alink to back that up? As Exxon/Mobils Ammco ATF MerconV says it can be used in older trans and current ones that call for Dex3/Mercon fluid

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Aamco MerconV is rated for both Mercon and MerconV. Many MerconV fluids aren't dual rated for Mercon/MerconV and Ford recommends against use of a dual rated Mercon/MerconV for many Mercon applications.

 

[FazerZ]

As suggested by the other responses, Mercon V should be used in your application. The use of regular Mercon/Dexron II/III will not cause immediate transmission failure. Given you have good fluid in place now, I would recommend visiting a transmission shop or transmission parts house and ask for Lubeguard Mercon V additive. It comes in a black bottle with a GREEN cap. This will add the necessary mix to bring the fluid into spec for Mercon V applications.

Mercon V is NOT recommended in older Ford transmissions/transaxles with stock front pump seals due to material incompabilities. It can cause seal damage and leakage in hard to access places (front of trans).

Exceptions are older AOD-E, 4R70W, and any rebuilt unit with Viton front pump seals.

It's doubtful any fluid changes are going to fix your slipping transaxles, but regular service may buy some time. Good luck.

DH

 

[Schultz]

I too had the same shifting/slipping problems with a sable that I use to have. After about 70k miles it started to happen. I dropped the pan and replaced the filter and fuild and it went away. About every 25-30k after that the shifting/slipping problem would come back. Each time I changed the fluid and filter the problem went away. After three changes I ended up selling it.

I now have a newer 98 Taurus, but this time I was proactive and I added a remote hydraulic filter and cooler to the trans. So far no problems with the trans, but it only has 70k miles