afriot

This is a "Heads Up" to those with a similar situation.

2011 Ford F150 Lariat, 5.0L, automatic (6R80), 4 x 2, Stock, Towing package (without verifying weight...9,800 lb), column shift

Our truck would occasionally not start. All dash illuminations which normally would come on did (fans blew, infotainment operated, etc.)...except for the gear indicator (PRND21) in which, the "P" is normally lit. We had trouble code P0705 (Transmission Range Sensor Circuit Malfunction (PRNDL Input)) or P0706 (Transmission Range Sensor Circuit Range/Performance), I don't remember which. But if either were the case, as told by Ford dealer, putting the vehicle into neutral would allow the vehicle to be started. Our vehicle would not start if put into neutral when the gear indicator (PRND21) was not illuminated when the ignition was turned to the "On" position. When no indicator was illuminated, the truck would not start. Repeatedly inserting, removing and inserting the key would eventually allow the gear indicator to be illuminated. Also, removing the key and opening and shutting the door would illuminate the indicator. As well as turning the ignition on, putting a foot on the brake and moving the gear shift lever through the full range of gears and back to park, turn off the ignition and back on would light the indicator to start t he truck could work too. Heck, sometimes even putting the windows down could seemingly allow the gear indicator to come one and we could start the vehicle.

I searched for nearly a year to find a logical reason as to why the truck would not start when cold. The colder the weather, the harder/longer it was to start the truck. After the truck warmed up I had no issue the rest of the day. Early this winter, we had colder than usual temperatures. The truck really began to get really hard to start. I again looked for a reason for our issue. I had a forum post looking for assistance. Eventually, I had a reply with the culprit part and an explanation that made sense. I tire of people who think they are helping by just spewing out parts that are or could be the problem with no logical reason other than "It's broken".

My instance was the lead frame attached to the valve body in the transmission. Small bits of metal filings circulate throughout the transmission. While there is a magnet attached (magnetically) the inside of the transmission fluid pan to trap metal particles in the transmission fluid, there are still many other places for metal particles to bind or attach themselves. Please correct me if I am incorrect. Sensors that use magnetic triggered "Hall effect" sensors and solenoids use magnetic fields to operate can pull metal particles into their fields. If the magnetic fields are the result of permanent magnets, the metal particles will stay attached to the sensor. If the sensors use electro-magnetic fields, the magnetic field will again attract metal particles suspended in the transmission fluid. Those particles may be released when power is suspended from the electromagnets. Like when your transmission changes gears by exciting an electromagnetic field inside a different shift solenoid or when you turn off your vehicle. The particles may fall away after the power is removed from the electromagnet or tolerances may be so close that they are packed/stuck in place and will eventually build up enough to alter the operation of the solenoid or sensor.

I ordered a new transmission filter, transmission fluid (I bought a case cheaper than I could get individual quarts), and lead frame (which arrived with a new seal not installed at the factory to be placed over the shift solenoid contacts). The transmission pan has a re-usable gasket. Just clean it with a cloth. The parts and fluid cost was about $200. Start to finish laying in the snow/mud under a vehicle that was blocked from rolling and raised 15" in the front and changing the lead frame on the valve body on the tailgate was 2 1/2 hours max with sandwich for lunch (my wife insisted).

Quick and dirty guide from memory (may not be 100% accurate):

• obtain replacement parts and supplies (Lead frame with seal, transmission fluid, transmission filter, 5' 3/8" plastic tubing (small enough to fit in dipstick hole), funnel that fits in tubing)
• vehicle undercarriage wash is recommended
• park on level spot
• block rear wheels
• raise front and block
• craft or news paper laid out on the the open tailgate if you don't have a clean work table. Hold down with rocks or extra tools of wind might be an issue.
• remove negative cable from battery
• remove electrical plug from rear of transmission passenger (turn lever anti-clockwise and remove plug)
• drain transmission fluid into large drain pan by removing transmission pan bolts (can get messy and patience is advised if you are not familiar with this task)
• remove transmission fluid pan keeping it as level as you can to empty the remaining transmission fluid from the pan and place pan out of the way
• remove transmission filter making sure to remove the seal that may stay in the transmission
• pull down on electrical plug keeper (mine was white in color) at rear of plastic lead frame on passenger side and remove plastic housing and seal from outside of transmission.
• remove larger torx bit screws to release the lead frame and valve body assembly from the transmission.
  • There is a spring/plunger combination above the passenger side about mid-way of the valve body that may fall out.
  • Also, there are black rubber tube-like seals (three, I think) that may stick to the valve body and drop down from the transmission. One stuck to the valve body when I removed mine leaving three in the transmission.
• place lead frame and valve body assembly on clean work area
• remove smaller torx bolts and remove the lead frame from the valve body
• clean fluid and metal particles from shift solenoid contacts
• install foam seal over the shift solenoid contacts
• install lead frame and replace torx bolts torquing to specs. and set aside
• clean transmission fluid pan and gasket being sure to remove, clean and replace the magnet on the inside of the pan
• install the lead frame and valve body assembly and torx bolts are torqued to specs
  • make sure the range sensor is located properly on the gear change lever so it will properly display gear selection
  • be sure spring/plunger is installed before bolting
  • be sure rubber tube seals are installed in transmission above valve body before bolting
• install electrical plug plastic housing and seal from outside of transmission and lock into place with white tab
• plug in clean transmission electrical plug and lock onto place by turning electrical plug lever clockwise.
• put seal that comes with the transmission filter on the long tube of the filter and insert into transmission as the old one was removed
  • please double check new filter with the old since it has been known to get the wrong filter. I was given one once that had a tube too long for the transmission. It would fit, but the pickup ended up being too far down in the pan and was sucking the transmission pan and was getting no fluid to the transmission.
• clean transmission fluid pan gasket surfaces
• install transmission fluid pan with cleaned gasket and torque to specs.
• remove transmission dipstick cover plug on passenger side of transmission just above transmission fluid pan. There is a hollow plug/cover and a plastic dipstick under the cover.
• insert tubing through passenger wheel opening above tire into the dipstick opening and pour in 7 quarts of Motocraft transmission fluid watching for fluid spilling from tubing or filler hole
• remove funnel and tubing
• replace dipstick and plug
• raise front end to remove blocking and lover front end
• remove blocking from rear wheels
• clean up work area and put away tools

I drove my truck for a couple days before getting my oil changed. At the same time, I had them check the transmission fluid. They had to add nearly an additional quart. Good thing I got that case of fluid instead of exactly the required amount for a filter change.

I have been very relieved that the truck has been starting reliably daily for three weeks down to -9*F.

Hope this helps someone, if not, I stayed dry typing this instead of getting rained on building a new chicken coop.

Spiky

Which year?

rojizostang

that right there is signature material!!!

Driftboater

Thanks for the detailed info, but it would really help forum members to know the year, engine, 4x4 or 2 wheel drive, differential (ELD, LSD and size) at a minimum, what options such as max trailer tow package etc, and any additional mods that may affect the transmission/ drive shaft/ engine - was it tuned, lift kit...

afriot

So sorry,

2011 Ford F150 Lariat, 5.0L, automatic, 4 x 2, Stock

That is all I know. Again, sorry for the lack of information. I will try to update the main post.

Spiky

There's a recall for that if you had less than 150k miles.

afriot

There was no recall for our truck. Called our dealer more than once over the course of nearly a year. Our truck has 159K miles, also. There is a recall I think for the same fix, but a different issue. The computer would apparently not know which gear the truck was in, maybe even traveling at highway speeds, and tell the transmission to shift into first! What a chance for a catastrophe! The recall will pay for dealers to replace the lead frame if there the proper diagnostic codes set related to an output speed sensor and only in trucks built from Aug. 19, 2011, through March 9, 2012 at the Dearborn Truck Plant in Michigan and the Kansas City Assembly Plant in Missouri.

I don't think there would be a recall for our no-start issue since it is not a safety issue unless you count living in an area where it does go below -20*F during the winter and you could freeze to death if your vehicle would not start due to an issue with poor engineering of a lead frame. Which I don't know if it's a design flaw in the lead frame but a flaw in the parts assembly. Originally, there was no seal between the lead frame and shift solenoids. This seal, I believe, keeps the metal particles from grouping around and coming into contact with the terminals of the shift solenoids. Maybe it's only the $7 seal omitted at the factory that's the repair and the lead frame is added in as an effort to head off a future replacement of the range selector and the two speed sensors?

Spiky

True, you had the wrong codes. No idea about the seal.

BeastofBurden

This is exciting! I have been struggling with this issue for 2 years and did not get anything useful when I posted to https://www.f150forum.com/f38/gear-p...center-495536/
I just checked and found that my VIN is part of the recall but I do not qualify. In Canada, the parts kit is $600 and 4 weeks lead time. Is the 2 year Ford warranty worth it?
This is a spare truck that I only need for towing up to 10000 lbs. Too thirsty for everyday use!

afriot

I cannot say as to value of the warranty. My experience has been that warranties are only good for the seller of the warranty. Meaning...no good for pre-existing conditions. I am sure there would be an inspection prior to the warranty being initiated. If your issue arose or could be discovered during the inspection, your claim would not be honored. I have become quite a skeptic of any business since their number one priority, despite their claims, is profit over customer service.

I do have to say, that despite my skepticism about big business, we love out truck, even with it's faults (lead frame and the MANY HVAC door actuator replacements). 240k+ miles and still strong. We had to change the oil pan gasket recently as it was leaking far too much oil to not repair it. During the change, I was going to replace all the bearing inserts for the rods and mains since it doesn't take long once the pan is off. I found there was no more than 0.002-0.003" clearance on any of the bearings I checked so I let them be. We have faithfully done oil+filter changes 5-7k intervals with 5w 20 synth blend to factory warranty expiration and full synth after.

That being said...it has always had a strange knock that sounds similar to a rod knocking. Non-existent after a fresh oil change to almost ominous when nearing oil change time. I think it has something to do with the VVT (Variable Valve Timing), but dealers were always not willing to even acknowledge it was there (Normal).

I hope my troubles and solutions can help others.