I drive an 04 FX4, and whenever I gas it, as to get on the highway real quick, I don't have a problem getting up to speed. But at about 70mph, the truck starts to shake, and the blinking check engine light comes on. Once I slow down to 40 or so, the shaking subsides and the light turns off. Any idea on what it could be without taking it to a dealer or buying a code reader?

Thanks for your help

 

Take it to a parts store; they should read the codes for you for free. It will really help with the stored codes, as it can be several things causing your fault at speed.

Once you have the code(s), go to Google, enter the code (should start with a P0xxx)in the Google search box. You will get several hits to sites that tell you what the code is reporting (error), and what item(s) can be replaced to fix the fault.

 

You can buy code readers for $39 now