Originally Posted By: W_John_C
http://www.bobistheoilguy.com/forums/ubbthreads.php/topics/3551387/1
If that can be of any help to you...
I did a multi-drain/fill over several different intervals throughout the time I owned my 2011 (purchased at 36,000 miles, totaled at 86,000) and only found that clean fluid merely maintained the transmission's shift quality. I found that my best results were after resetting the KAM (battery disconnect, etc) after doing a fluid change. This allowed the adaptive functions of the transmission to get used to the new fluid each time. I changed it immediately after I got it (fluid was extremely dark) and about every 15-20k miles after that. I did take it in several times to make note of undesirable transmission shift quality, and I kid you not, I was told by two different dealerships that I had "one of the best shifting Fusions" they'd driven with transmission concerns.
On my latest fluid change I used Redline D6 with Lubegard Red (as you'll see by checking that thread) with excellent results. I did pair this with using premium fuel for what I found to be the smoothest driving it's ever given me. There's no question that the 6F35 is far from an ideal transaxle, but I think that as long as the fluid is maintained, you should be in pretty good shape. It would probably be wise to add an in-line filter to the unit as a just-in-case sort of thing, but then again, since you're still under powertrain warranty, don't overstep boundaries TOO much.
As much as I loved the car in every way, and planned to keep it for a very long time, I did end up buying an extended Ford ESP warranty to have just in case on the powertrain. Beyond that, it was one of my favorite cars yet.
Thanks. That is very helpful. In fact, I considered using Redline D6 and a Magnifine inline filter, but many people on fordfusionforum.com argued against those ideas, saying that they would void warranty. Some people said the inline filter can mess up flow of the fluid, which will cause damage.
I used Steeda CAI and 87oct and 91oct tunes, but they did not improve shift quality. Maybe the template from SCT for my car has problems. CEL came on every time after flashing, and the error code was P06B8.
The improvement with the new PEAK ATF is not obvious. Shudder fixx made the problem worse. Lubegard platinum made noticeable improvement. I wonder how it compares to Lubegard red, but the costumer service of Lubegard told me that platinum is better.