How do I adjust chassis height ?

If the height is in spec, leave the valve alone. You'll mess with the driveline angles and end up with vibrations and excessive u-joint wear.

 

What is the issue you are trying to fix? Ride height valves don't randomly change height. What type of truck and suspension?

 

Are you eyeballing it or using a tape measure.

 

What I have done before is if you think it's set to high then just drop a little air while driving not too much and see if it gets better if it does then you know for sure it's to high and if it gets worse then it's either set to low or some other issue possibly a u joint

And as far as adjusting the height control valve it's just 2 bolts that need to be backed off a bit and then you turn the valve assembly to raise or lower the truck

hope that helps

 

If the bolts have not got louse and let the valve move, then you will need a new not rebuilt ride height valve.

 

Sounds like it’s Not allowing air to dump properly, only airing up. You can disconnect the rod at end of arm, and check operation of valve. Pushing arm up, adds air, arm down, air should dump out. If not, valves bad. Look at the way arm mounts on valve. Usually 2 bolts. 1 on end of arm, another that’s slotted. Loosen both, adjust the arm position on the valve. The adjustment may be on the mounting bolts on valve itself, that is, arm is bolted stationary on valve, and valve itself has slots in it for adjustment. Play around with it, you’ll figure it out. Most importantly ofcourse is to get height set correct. I usually make a template, from cardboard, cut to the correct size, and use that as a “ spacer”. or guage. Easier than tape measure