Well, after reading Barry Beams instructions on setting ride height, we gave it a shot. Rears were straight forward. My unit has the IFS which has only one adjustment up front. In reading Barry's info it says to measure from the top of the base plate to the bottom of the upper plate. This is where it can vary 1/2". Does the top mean at the top of the air bag at the first indention or is it the second indention which is actually just under the steel plate? I was understanding the travel distance. If that is the case then the first indention would be more accurate? This round looking doughnut piece appears to be part of the airbag but is hard and can't tell if it is part of travel distance.
If you are setting at 8 1/4", this could make it vary 1/2". Also, it was much more difficult to adjust the front. Any tricks on how to do?
Before setting the left front was about 1 3/4" low. Right rear was 1/2" high.
Thanks for all your input.
David
The 8" measurement is between the mounting plates that are welded to the frame members. If you want to include the plates in the measurement just add 1/2 inch as each plate is 1/4 inch thick. I include the plates and check for 8.5 inches. The rounded metal at the top of each air spring/bag and the curved thing (called a piston) at the bottom is considered part of the air spring for measurement purposes. The fore and aft springs/bags at each axle corner operate as pairs. If one of a pair is more than 8" the other should be an equal amount less. The front can be this way also side to side if the coach is not on a flat surface when the measurement is taken (assuming the rear sides are equal height). If the ride height needs to be increased, the distance between the clamps on the rod needs to be increased. Be sure the ends of the rod are under a clamp when finished and not just stuck in the rubber. An "L" shaped piece of plywood with measurement marks at the top make this task easier to do. The bottom of the "L" is rather short.
Jerry,
Very good explanation. That clears up that top area. It was a bit confusing. Thanks for the tips also. Any info on the front adjustment since there is only one for both bags?
David
Try to find an absolutely flat level paved spot. Do the rear first. About all you can do with the front is try to get a reasonable average of the correct height on all 4 bags. None of them may be exactly the same correct 8 or 8.5 measurement. If the average was 1/4" low lengthen the rod distance between the clamps 1/4". You have to go under the vehicle to do that, so you should raise it first with the bags and install safety blocks between the frame members. You are working with a leveling valve so it could crush you without the safety blocks. Make the adjustment. Remove the safety blocks and return the system to travel and start the engine and wait a minute or 2 to reach travel height. Recheck the measurements, and repeat if necessary.
Some wear in the ride height valves can drive you crazy when trying to set the height.
Dump your coach and then let it reinflate itself several times. If you measure the bumpers all around each time are the numbers the same? One or more of my u320's valves stick and the ride height varies. Then the coach does not steer straight.