can anyone with ford tranny experience shed some light on this?
I'm batting squirrel nuts on Ford pasenger car trannies..
I have a 2007 Mercury fusion (Milan) with the 5 speed FRN5 auto. This car has been nice for over 100,000 miles, but the trans is acting up now. The 3-2 downshift is harsh, and now throws the wrench light. The dealer reprogrammed the PCM, and they did a fluid swapout. Supposedly, it still has the shudder. Below is a list of observances that the cars has presented. I gave this list to the dealer..
In for Transmission shifting issue
Last 4-5 months, the original battery has been real weak. In the last month and a half, the car has had a dead battery on a few occasions. Three weeks ago and new battery was installed. The trans issue started prior to the battery replacement. I was postulating that the battery was causing the trans module to lose its programming or something. New battery did not fix.
If I remove battery cable, it would run fine for a while, but the 2-3 upshift was a little rough, and the 3-2 downshift was harsh.
The wrench on the dash came on, and the trans would shudder violently when placed from park to reverse, acting like it was put into two gears at the same time.
For 3 weeks, the trans worked fine, as long as I dont have it in gear when I slow to less than 25 mph. I would shift into neutral when approaching a stop. If I did not do this, the trans would go directly to 1st and the engine revs would go to 2500-3000 rpms. Once this happens, I would have to shut the engine off and restart, which would sometime work, but usually I would have to disconnect the battery for 5 minutes.
While driving the car to your dealership, the car started acting up again, not knowing what gear to be in, and/or the convertor was locking and unlocking. It was acting like a sensor was wigging out, causing bad data to be supplied to the trans module or something. I would guess that the learning part of the module would be compromised when given bad data to interpret.
The trans has not has a fluid flush, and definitely needs one.
For at least 3 years, the trans would occasionally, during the 1-2 upshift, rev to 2000-2500 rpm before shifting when cold, but not all of the time.
Other issues include the secondary air pump system, and the cooling system.
I was getting a P0128, coolant not up to temp. A thermostat and coolant temp sensor change seems to have fixed that.
Codes P0410 and P0491 came up, secondary air pump system, I hotwired the pump at the relay box, the pump sounded like the brushed were bad, as it sounded like intermittent operation. Upon removal of one of the hoses, the pump was full of water. Research provided info of the control valve not closing letting in condensation from the exhaust. The valve was removed, and it tested OK. The vacuum lines were checked, and found a hole in side of line due to rubbing on the engine. I repaired line, codes show that ODB-II is still pending. I do not know if the vacuum line issue affected the other issues with the car.
The CEL codes have been fixed. I am wondering if the weak battery started all of this. I read a thread on the forum where that owner had a similar issue, which was fixed with a fresh battery.
I talked to an independent trans shop in town that has a very good reputation, and they suggested adding a friction modifier to the fluid to help the shifting. It seems that solenoids are sticking and causing the trans to try to engage two gears at once.. I am going to try this, because I have nothing to lose. I can get a used trans for $400, but am concerned that an issue external to the trans is causing this.