Customers who own a 2009 to 2011 Ford Escape or Mercury Mariner using the 6F35 front wheel drive transmission might complain about a hoot type noise on light acceleration just before the 1-2 up-shift. As in the previous newsletter this month, this is yet another problem that is not a problem.
Ford/Mercury considers this to be a normal characteristic of the transmission (Ford TSB 11-7-23), making this is the first transmission ever documented that gave a hoot! However, should the customer insist on hooting himself saying, “It wasn’t there before,” you can hazard a partial repair as there is an updated chain snubber part number BL8Z-7J387-C that will “reduce” the noise. This repair will require transmission removal and dismantling, so it’s a big job just to reduce a noise complaint.
It might go along way to replace this snubber when doing a major overhaul. The driver will notice a quieter ride giving the perception of having a better transmission than what they had previously.
The same vehicles including the Ford Fusion may also experience a harsh 2-3 up-shift and a flare 3-4 when cold. This complaint has a reprogramming fix per Ford TSB 10-21-9. If the 1-2 shift is harsh and 2-3 shift is hard for the first couple shifts of the day along with an intermittent harsh first engagement (reverse especially) and there are no codes, this too can be remedied by reprogramming (TSB 11-12-8). Some of these vehicles also will develop harsh shifts followed by a default into fifth gear with code P0720 and/or P0722 set for OSS issues.
If the fluid is not burnt, the internal lead frame or OSS will need to be replaced. This lead frame has a Julian date on it with the first two digits indicating the year while the second three digits indicate the day of the year. Lead frames not to be used are 09184, 09185, 09186, 09229, 09230, 09234, 09235, 09236 and 09237. If the lead frame used has one of these numbers it will need to be replaced with part No. 9L8Z-7G276-A. If it does not have these numbers the OSS sensor will need to be replaced with part No. 9L8Z-7H103-A.
Another issue with these vehicles including the Milan fixable via reprogramming occurs after the customer used a feature called the “Grade Assist” option. While in Drive there is a transmission control switch (location model dependant) that activates grade assist and cancels overdrive. This operation provides additional engine breaking and extends lower gears operation for both uphill climbs and downhill grades.
There is apparently a problem using this option causing these DTC’s to set: P072F, P073A, P073B OR P07A8, P07A9, P07AA, P0731 and P0732. Performing the reprogramming procedure per Ford’s TSB 10-12-12 will remedy the complaint.
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