Under acceleration the vehicle shudders, and shakes. It seems to lose power for seconds before it picks back up. Has happened several times while pulling my camper and passing vehicles on highway and interstate. The other day while driving down the parkway the truck down shifted from 6th gear to 1st or 2nd without warning. I was almost rear ended and had to drive off onto the shoulder to avoid the collision. I have contacted Ford and I will be taking the truck in for warranty work on Wednesday April 6th 2016. I only have 3K miles left on power train warranty and none left on bumper to bumper. I purchase Ford vehicles cause of there long lasting and reliable reputation. I have two children and wife that I expect to keep safe while driving this truck. I hope Ford will look deeper into the problems at hand, dont be like GM and kill people before you fix the issues.

- Meridianville, AL, USA

The contact owns a 2011 Ford F-150. The contact stated that the vehicle stuttered violently, while driving at various speeds. The dealer replaced the spark plugs and the spark plug boots. However, the contact felt that the repair would not be a permanent repair. The manufacturer was made aware of the failure. The failure mileage was 15,000.

- Hummelstown, PA, USA

My F-150 supercrew 4X4 with ecoboost engine began misfiring on hard acceleration situations, such as merging and changing lanes on the interstate. After approximately 2 months, the issue has gotten worse to the point of misfiring under normal acceleration. The jerking from the misfire condition is quite violent, and I believe to be unsafe. This is a known issue related to the design of the trucks intercooler. Condensation builds during prolonged highway driving, particularly in humid climates. I am in Arizona, but I drive 50+ miles a day on the freeway. The NHTSA dropped their investigation of this unsafe condition, apparently agreeing that Ford's tsb was sufficient in dealing with the matter. My truck is not under warranty, however it exhibits a design flaw that is unsafe. How is there not a recall on this? disappointing.

- Tucson, AZ, USA

I own a 2011 Ford F150 ecoboost V6. For the past year, the engine will quit making power under acceleration when merging onto a highway or passing. I currently have 65000 miles. Ford has told me there are no recalls and invited me to spend my money in their service department when this is clearly a known issue. This is clearly and unsafe issue and just a matter of time before someone attempts to merge on a highway and is hit by another vehicle because the truck suddenly lost power.

- Island Lake, IL, USA

There are @ hoses that come out of the radiator and go into a hard plastic T-piece (part number dr3Z-8566-a) and there are O-rings inside of it. Mine started leaking and I was informed that I had to replace the whole piece no big deal. Then the dealer ship went on to tell me that they have replaced 6 in the last 2 weeks of the same exact year and model. The dealer ship is in lima Ohio. That being said if there are so many of these that are going bad and the vehicle only being 5 years old I feel like there is obviously a defect in the part/ design of it that causes it to fail.

- Kenton, OH, USA

When accelerating, especially going uphill, the engine makes a repetitive whooshing noise.

- Orleans, VT, USA

The contact owns a 2011 Ford F-150. The contact stated that while driving at 55 mph, the vehicle failed to accelerate when the accelerator pedal was depressed and the gauges in the instrument panel began to fluctuate. The check engine and the wrench warning light illuminated. In addition, the gear shift indicator began to change rapidly. The failure recurred intermittently. The vehicle was not diagnosed or repaired. The manufacturer was not made aware of the failure. The approximate failure mileage was 75,000.

- Tabernacle, NJ, USA

My 2011 Ford F-150 with the ecoboost package will stall upon acceleration. The engine light will flash momentarily. This is a safety issues as it causes the vehicle to act in a manner that inst predictable when changing lanes on an interstate or passing. This has happened on multiple occasions and a simple google search indicates this issue is widespread with this model.

- Pineville, LA, USA

Engine coolant is overheating. Engine coolant temperature gauge in the normal range ( between H and C ).transmission fluid temperature gauge (between H and C ). gauge detail- ---- trans temp -195 - 210 F.20 minutes driving (not towing ).check the level of the coolant in the reservoir --- low!!!. adding 1/2 gall -5O/50 mixture coolant. 02/16/2016 - apple Ford (columbia, md ) check engine cooling system. --- found coolant tank and coolant hose from tank to heater core leaking. Car mileage-44117. Car for life oil and filter change, mulitpoint inspection.

- Silver Spring, MD, USA

Truck has loss of power when pulling out to pass at highway speeds nearly causing head on crashes.

- Henderson, NV, USA

2011 Ford F150 lariat - when accelerating to pass, engine lights will flash and the truck will lose power. After several seconds of flashing, the engine light stays on and the truck decelerates. I shut the truck off and then re-started but the engine light stayed on. I was traveling on a highway and had to pull off to a city street. Very dangerous situation.

- Oneida, NY, USA

Upon downshift during acceleration, the truck shudders, misfires, backfires through exhaust system, and loses power while creating a violent shake in the drivetrain. This occurs in below 35 dry or wet weather. This issue destroyed my catalytic converters, as well as broke loose the baffles in factory muffler causing over $2,000 in repairs for exhaust. I further replaced plugs, and plug boots. The vehicle continues to have this severe issue, and the only way to keep from further damaging the vehicle is to pull off the road, and idle as well as rev engine for several minutes. It is extremely unsafe, and nearly caused other vehicles to rear ended me on at least 5 occasions. All of which I had to jump onto shoulder of road or in median to keep from getting hit. My research shows that this is a common problem amongst owners of this vehicle. I currently owe $22,000 on this vehicle, and am quite frustrated with the lack of a recall from Ford. Solutions of a walker cac are known; however, Ford is not willing to even consider paying for this fix. Please help in the resolving of this issue?

- Lindale, TX, USA

Fault log code P0234, turbo noise hissing, cutting out. Loss of power. Poor acceleration. Coolant leeks, oil leeks. Returned to corning Ford for more service work. Original service October 11 / 2015. Second service December 28 / 2015 coolant leek, turbo hissing, cutting out hissing when under acceleration. Condition when in motion on city street and highway driving.

- Red Bluff, CA, USA

Vehicle has been sputtering & missing. Heavy hesitation on acceleration. On 12/01/15 my truck equipped 3.5 ecoboost started missing upon acceleration then lost all power and started to shake vigorously. After taking it to the Ford dealership for diagnostics they returned with saying my engine, turbos & crankshaft are damaged and must be all replaced. I am within the 5 year warranty but exceeding the mileage with 71,000. Myself & holmes tuttle Ford filed a claim with Ford both being denied any help.

- Tucson, AZ, USA

My vehicle as been miss firing since it had 20,000 miles. I have been involved in almost 2 accidents because upon merging onto oncoming traffic my vehicle will misfire, slowdown and will not speed up fast enough to merge onto the highway safely. Because of this I have almost been hit twice by an 18 wheeler truck. I have taken the truck back to the dealership and they stated the miss firing due to air cooling system and it destroyed my catalytic converter. The dealership replaced my catalytic converter and installed some type of cooling shield, and now at 110,000 miles it's miss firing again and running sluggish. The cooling shield that was installed did not fix the problem at all. Not only is the on going miss firing life threatening but has destroyed my catalytic converters twice which is causing my emissions to emit harmful smog into the environment. Isn't their emission laws automakers must abide by? the miss firing is messing up my emission's which is harming the environment too.

- San Marcos, TX, USA

Engine stall-shuts down when it goes into passing gear. When you attempt to pass or enter onto a highway you accelerate and the engine shuts down

- Tallahassee, FL, USA

Ford F150 3.5L ecoboost completely looses power when accelerating in passing gear. Vehicle shutters and bucks severally and does not allow any type of acceleration to be able to exit into slow lane interstate traffic. Normal operation returns after about 1.5 minutes of coasting and then gently applying accelerator to regain vehicle control. During the recovery time the engine runs very rough as if timing was completely out of sync.I drive 1000 miles per week on interstate 95 and this condition is ongoing. I experience at least 2 or 3 of these episodes per week when I try to accelerate to pass another vehicle. This is a safety concern to me because the vehicle looses power completely and does not recover until 1.5 minutes later. The check engine light comes on very time this condition occurs. When reading the error codes it only show misfiring of all cylinders (code P0300).

- Port Saint Lucie, FL, USA

Engine losses power and shudders badly when trying to accelerate to over take. Engine light comes on and when diagnosed says misfire number 4 cylinder, checked and installed new plug and coil after 50 miles the same problem and dealer says they can not fix issue. This is the third time this has happened after coils have been replaced. The replacement coils were oem motorcraft units. In reading about this problem it appears that this power unit has a large number of complaints and issues.

- Victor, ID, USA

The contact owns a 2011 Ford F-150. The vehicle stalled without warning while driving 40 mph. The vehicle resumed normal function after restarting the engine. The vehicle was taken to the dealer where the failure was unable to be determined; however, the dealer discovered that the coolant system was not separating the sludge causing the sludge to penetrate the engine and activating the vehicle limp mode. The contact stated that the vehicle was not repaired. The contact stated that he would install an oil separation device to the vehicle independently. The manufacturer was not notified of the failure. The failure mileage was 31,263.

- Applevalley, MN, USA

The contact owns a 2011 Ford F-150. While driving approximately 45 mph, the check engine warning light illuminated. In addition, when the vehicle was started, there was an abnormal noise under the hood of the vehicle intermittently. The vehicle was taken to an independent mechanic where it was diagnosed that the timing chain failed and needed to be replaced. The vehicle was not repaired. The manufacturer was notified of the failure. The failure mileage was 65,000. Update 01/13/16

- Wyoming, MI, USA