Suspension weight ratings

I don’t know if this is the correct place to ask this question, but I been searching online for the Peterbilt Flex Air weight rating.

as far as I found somewhere it said that it came for 38k on the suspension(flex air) and the differential are Eaton 40k

my truck has Flex Air, so I’m guessing my tandem weight limit is 38k?
Or is there different ratings for Flex Air? I know someone who has grossed 105k, which would put his trailer and tractor tandem at ~46k.

 

the rears are rated for 40k, but the Flex Air suspension is supposed to be rated for 38k hence my question.

https://www.pbtruck.com/Parts/Catalogs/Peterbilt-Suspensions.pdf

if you look at this chart it shows Flex Air as 38k. Just wondering if there’s other ratings

 

I suck at seeing replies here. That’s what I was thinking but almost always there’s information I don’t know about and like to double check.

 

So I finally got around to checking my door sticker(I was in another).

my door sticker says:

gvmr: 50,000lbs
Front axle: 12,000
2nd axle: 19,000
3rd axle: 19,000

which would total at 38k for the Flex Air.

but this confused me. My brother has the same truck but a 1999.

This are his specs with a Low Air Leaf

Gvmr: 48,000
Front axle: 12,000
2nd axle: 18,000
3rd axle: 18,000
And we always assumed his was a regular 40k tandem and he has permitted up to 46k on those and driven many miles, I asked him if the DOT had checked that before, he said, they just look at the permits and send me on my way.
Another friend with a 90s 379 as well, showed me a Class 1 inspection he had today and he also had a GVWR of 48,000 with low air leaf. As far as I know, Low Air Leaf was 40k yet they have lower GVWR than my Flex Air.

 

I agree about the wear points, I haven’t driven a low air leaf in 8 years so I can’t really compare the ride. Only thing I have against flex air is they lean a lot on curves.

but my truck is lighter, with a heavier engine, I think the Flex Air is supposed to be 400 pounds lighter.

my big question was on weight ratings, but according to Peterbilt they gave Flex Air a higher axle rating than both of the low air leaf that I looked at. So I keep scratching my head about the tandem weight limit.