Try Color Back made by Turtle Wax
Turtle Wax T-270R1 1-Step Color Back Oxidation...
This is by far the best product ever made by Turtle Wax. It doesn't require a ton of elbow grease. Just several towels. Just rub it on and then rub it right back off. It will clean ALL of the oxidation off and will leave your original paint looking great. It really is amazing how fast and easy this stuff works. You will have to wax your truck right after using this.