2001 Freightliner ClassicXL suspension issue

[Jimmyhoffa816]

I have a 2001 Freightliner ClassicXL and have noticed that the rear air bags are about 1/2"-1" higher inflated than the front drive bags. But when I pulled it out from underneath a loaded trailer (about 30,500lbs on drives) and aired up the suspension all bags were the same. But once back under trailer the back bags got taller than the front bags. To the point where they look like they are almost fully extended (atleast what the shocks will allow) I just put all new shocks all around the truck. I've seen a few posts about this issue but never seen a resolution. And have seen trucks going by just today that look almost the same. I've been in trucks my whole life and have always done my own maintenance work. I've done my own engine swap and timing of my N14 I know my way around a wrench but I've never seen bags differ like this. There is only one leveler valve. I hear no leaks my truck has been sitting for around 4 hours and only lost about 20 psi of air. Also the left bag is angled (I've seen this issue on ClassicXL's before again not sure what causes them) any input at all would be appreciated. If it matters my truck has 24.5LP tires and my trailer has 22.5 LP tires springs look good. Rear drive axle is tilted back (as in the top is tilted towards rear of truck slightly) assuming this is for the middle drive line/ujoints. Thank you in advance for any help or advice

[regulator]

2 questions,

1. What type of air ride do you have?

2. With the low pro on the trailer do you have a lowered fifth wheel pedestal or does your trailer bottom look like it's going uphill while attached to your truck?

[Jimmyhoffa816]

How would I find out? My spring hangers say airliner on them?

And I just measured from bottom or trailer to ground in between drives and it's 45 1/2" and then measured the same way on trailer and got 41 3/4"