Need advice on changing tranny fluid and filter on 2004 Navigator.

[heyjewel]

Hello. I need to change the fluid and filter. I've done this on my LS but never on the Nav. Since locals want $150 for the flush and $150 more for the filter I'm inclined to go the do it myself route.

What are the tricks to this job? Just slowly drain the fluid out of the pan, then remove the pan, clean it and the gasket (I read it's reusable) then R&R the filter, put it all back together, add as much fluid as I drained and drive happy? I know this will leave some fluid in but I don't have capability to flush the rest out.

But what fluid? Manual says Mercon and ONLY that, no dual use mercon or mercon 5 ever. I thought 5 was back compatible with mercon but this says NO.

Some parts stores sell a kit with a filter and gasket. Even though gasket is supposed to be reusable I'm thinking to get one anyway. Thoughts?

Thanks. George

 

[lincolnelite]

just do a drop and fill, no flush
everything is Mercon V now.

 

[heyjewel]

Yes thanks but do not mix mercon and 5 is what I'm told. And if the tranny has plain mercon in it and I don't flush ...

 

[Mark Kovalsky]

That was true back in 2004. It not longer is true. MERCON V was changed in 2006 to be compatible with MERCON. MERCON was then discontinued. NOBODY produces a licensed MERCON fluid, and hasn't since early 2006. Any fluid that now says MERCON can have any properties the fluid manufacturer wants. It doesn't have to meet the MERCON spec because there is no longer a MERCON spec.

I highly recommend flushing the fluid. DO NOT use chemical additives. Here is one procedure on how to easily do it yourself. http://www.ford-trucks.com/articles/changing-atf-fluid-in-a-e4od-and-4r100-transmission/

 

[heyjewel]

That was true back in 2004. It not longer is true. MERCON V was changed in 2006 to be compatible with MERCON. MERCON was then discontinued. NOBODY produces a licensed MERCON fluid, and hasn't since early 2006. Any fluid that now says MERCON can have any properties the fluid manufacturer wants. It doesn't have to meet the MERCON spec because there is no longer a MERCON spec.

I highly recommend flushing the fluid. DO NOT use chemical additives. Here is one procedure on how to easily do it yourself. http://www.ford-trucks.com/articles/changing-atf-fluid-in-a-e4od-and-4r100-transmission/

This is exactly the information I needed. Thanks Mark. And thanks for a great step-by of how to do it. I know the fluid's been changed only once in 140,000 miles. Yeah hit me again. And the filter has never been changed AFAIK. So I'm going to change the filter, flush the fluid, replaace with Mercon V and reuse the pan gasket. As soon as I get done doing same thing on my silver LS which has been on jackstands since before Christmas awaiting my return.