I have a friend who has a 2004 ford f150. The check engine light and abs light is on and the truck jolts like is trying to shift gears a steady speed. What might be the problem?

Take it to Autozone, Advance, or Oreilys for a FREE scan. Since a problem light is on, the computer will tell you what part is bad.

The ABS can have a problem reading the RPM of each wheel if there is dirt or debris blocking a sensor. Common problems are the rear Emergency brake shoes coming apart within the drum portion of the rear rotor. The rear of the truck has 2 braking systems, an Emergency brake and a service brake.

The ABS portion of your problem can also be scanned with a better scanner having more functions. The "Check engine" light is on a separate system and most minimum priced scanners will work with it. Since the ABS is automatically operating, a malfunction can result in a jolt as the individual brakes are wrongly applied.

The ABS will apply the brakes to the fastest spinning wheel and this will result in a drivetrain jolt.