<https://www.bigmacktrucks.com/topic/25721-cab-air-ride-wont-raise/#comment-124526>
<http://schema.org/text>
"HI, if neither the seat or cab will raise it's the little pressure protection valve. This valve limits air pressure going to seat and cab leveling valve. Don't know on an RD exactly where to tell you to find it, but it will be on an air tank. \n"
<https://www.bigmacktrucks.com/topic/25721-cab-air-ride-wont-raise/>