Not really. Buy 4 T's and 4 gauges. Mount them permantly. You need measurements when you are loaded. And you need to check those,what i suspect to be,stopblocks. Maybe get a picture off them. I think you have 2 issues which are happening at the same time.
Find out the max air your tanks will hold. It should be at least 120 PSI. Turn on your truck, and raise your RPMs to 1300. Watch your PSI needle, and you should hear a popping sound once your air tanks max out. The popping sound should be coming from your air dryer purge valve. If the popping sound is at 110 PSI, then there certainly is something wrong. While driving, it’s normal for the PSI needle to rise and fall. If the PSI goes under 100 or 90, then there is likely a serious air leak to the point that your air compressor is struggling to fill the air tanks. In my truck, my air tanks max out at around 130 PSI, and my air compressor starts supplying air once the PSI needle reaches around 105. As for the amount of PSI the tanks should have overnight, you “may” be okay by other people’s standards. Personally, my air tanks need to have at least 75 PSI after a 10 hr break on most days and with the exception of cold weather under 30 F. Lots of trucks have air leaks all over the place. It can be a challenge to find them, but it’s not rocket science. I posted a couple comments here that can help you find air leaks. Suspension air bags deflating
I personally wouldn’t know how. I would think it’s similar to installing a Right Weigh load scale that uses an airline from one airbag to give you your weights on your truck drives or trailer tandem. I’ve heard you can install any PSI gauge for this purpose. You may need some conversion adapters to connect the airline to the gauge.
I purchased a used Volvo 770 /2001 back in 2003 from Arrow, they used to have 30 days return policy. What engine transmission do you have ? The first symptom when leveling rod breaks and airbags lose air is grinding noise in driveline, diferentials can get damaged driving like this. I would also drop the trailer landing gear until get fixed, or unhook when you park and air presure drops, dont let the weight sit on driveline u joints.
There has to be a problem with the stop blocks. Somethings missing or broken. Maybe axles were swapped out and had different stop blocks on other truck? Tire sizes maybe changed also at the same time? Maybe different size stop blocks for 22.5 lo pro vs 24.5 tall ? Very strange, broken spring hanger pin?
Have you checked ride height already?? If you search on here in Volvo section you will find PDFs how to do it. Removing cross member is like putting band aid to your problem not a real fix imho dumb idea to modify frame or it’s components. I assume you do drop and hook daily dry van or a reefer mostly loaded?? I had a year ago a little problem with my air valve that control ride height. After dropping airbags with a button in a cab, pressing back on a button won’t inflate the airbags. So I had to climb under the truck in between the axles disconnect the rod at a buttom, use a screwdriver to pry on a rubber grommet, and manually push it up or down don’t remember to make it inflate the airbags a little over normal and put a rod back on a stud. After it would work all good till I replaced the valve. You might wanna try to manually overinflate the bags a little after you pick up loaded trailer and see if it will help at all.
So one person thanks it looks low due to height of frame and tires. Another thanks it looks low because of if air bag height. I thank it is low due to the angle of the torque rods and how close the u-bolts are to the frame. It could be low. Adjust the leveling valve. When I saw the picture of your drive line I recalled this. Some trucks came with sealed u-joints. They never need grease and you cannot grease them. They are assembled with special lubricant and good for the life of the u-joint. One had the cross seize to the cap and busted the yoke. It also took out 2 brake chambers and about $800 worth of valves and such. Its life was over! They had a plug in the center of the cross. Had to drop the drive line in order to swap them for grease fittings on the other trucks. S-cam housings were the same. Others must have similar thoughts.
To check air pressure in your air bags you will need air line of the same size a tee same size and a pressure gauge. Dont cut no air lines. Remove the line from air bag put it in a tee then short piece( 5-10in) from a tee into air bag and long piece(4-5 ft) from gauge into a tee. You can move this set up from bag to bag. I bought this gauge from local shop that sells parts for trucks and tools for shops something like a fleetpride Try calling this 2 places
Oh, I've been in 10s of Volvo shops for air ride hight adjustment and got different numbers from all of them. I remember reading here, should be in between 7.3/4 and 8 inches measured , from the middle of axle to bottom of rail, someone sugested is different for every VIN# to check with volvo shops. Wireless tpms are getting cheap, this model is around 70$, should be possible to adapt on each air spring.
What gauges do you installed on your truck, maybe got a part number or name of the place where you got them from??Can you post a pictures of how you mount them just very curious of the set up??
