On my 2011 ford f150 when i get between 40 to 45 miles an hour my truck bucks and shimies why
what motor does your truck have?
Your truck is miss firing check your plugs, distributor, or fuel injecters
If your truck has the 3.5 ecoboost you probably have a problem with the intercooler they have a updated design to help with the build up of water causing a misfire. Its usually under hard accel but it could do it anytime. And seeing how a 2011 f150 does not have a distributor its not that. I havent seen any injector problems on 2011's if your close to 100k miles your could need a tune up. Ignitoin coils are known to go bad it has one per cylinder. But knowing the motor and how many miles would help
my truck did that same thing 1 of my coil packs was bad changed it all ok now
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