what is the recommended top speed while in 4WD in my 2003 f150 supercrew 5.4L triton?
If you are shifting into regular 4wd, it is recommeded that you don't exceed 50-60mph although different manfacturers recommend different speeds. If you are shifting into 4L, which changes the gear ratio and is for extreme extreme conditions, it is recommended that you dont exceed 30-35mph. Again, it may be different depending upon manufacturer and year of the vehicle. The owners manual should let you know what is recommended for you system.
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