It’s concerning to hear about your truck’s difficulty maintaining highway speeds. This issue could be related to a number of factors. The most common ones include fuel delivery problems, airflow issues, or even transmission troubles. It’s also possible that your truck’s computer system is misreading conditions and limiting power as a result.
I strongly recommend getting your truck checked by a professional mechanic. They can run diagnostic tests to pinpoint the exact cause. Please don’t ignore this issue, as it could potentially lead to more serious problems down the road.
Drive safely, Mike!