New 5th wheel and towing issues

hi everybody it's been a few years since I've been here and I'm back with some issues that I hope someone can help with ....we recently upgraded our 31 foot travel trailer to a 38 foot fifth wheel and we are having some towing issues and don't know what to do about it ... we've talked with people at the camping place and the garage that worked on our truck recently ...seems like no one seems to know what to do... we have a 2003 Dodge 3500 Cummins turbo diesel 5.9 automatic quad cab I'm pretty sure its a 3.73 gears .short bed We have a husky sliding hitch ...on a recent to adventure with this new camper we were all over the road it was handling terrible it was a white knuckle experience... We recently had a lot of work done on the truck to get it ready for the new camper including new tires shocks airbags, steering box as well as a number of other things ...the tires were at around 80 psi on the truck ..and I want to say 50 on the trailer does that sound about right? The air bags were at 75.....are air bags a bad idea? what do you think this issue with all over the road was... Don't know any thing about pin weights and G VCRs and all that **** ..if .anybody could just help out a little I would truly appreciate it ....my husband is just all in a tizzy.thanks ..here is the specs to the trailer.....the hitch is right over the axel...please let me know if you need any more information That I may have not mentioned here .thank you so much..



Hitch Weight
UVW
GVWR
CCC
Exterior Length
Exterior Height
Exterior Width
Fresh Water
Gray Water
Black Water
Awning Size



385BH

1,940 lbs.
12,320 lbs.
15,940 lbs.
3,620 lbs.
41' 1"
12' 10"
100"
64 gal.
83 gal.
86 gal.
16 ft

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