Brit, Like dsbear, when I had new tires put on the ride got even smoother. My coach originally had Michelin and a buddy of mine that owns a tire store recommended Double Coin. They were on the lower side of cost and I was a little skeptical, but after some research I agreed to buy them and they have been outstanding with driving and wear. I've got right at 30,000 miles on these tires and could not have asked for a better tire. (Not promoting them, just my own opinion on these tires).
When I purchased my Astoria, the deal came with the RV being delivered to my house in TX from AZ. The gentleman that drove my DP said he had been doing it for about 14 years after an early retirement. I had a really interesting discussion with him as he told me he had driven million $+ Prevost that didn't drive as great as our entry level Astoria.
Not really know the gent, I wasn't sure how to take his comments until he explained he worked for himself and not the RV dealer(s). That just made me feel better thinking he wasn't trying to justify the sale of the RV to me.
For what ever reason, our 2005 Astoria drives like a dream and is unbelievable to drive. I have had buddies riding with me that have made comments about how relaxed I am and how smooth the rig moves down the road even pulling a 20' VNose trailer with 5 Harley's in it..
I even have one friend that has driven our Astoria 3 times now and this last time he cursed at me. I asked him what was up and he said "your killing me having me drive your bus. It drives so great it makes me want one really bad." LOL.. He keeps asking when I'm going to upgrade so I can sell this one to him..
Anyway, I wish I knew what is causing mine to drive so well and smooth and hope you find the driving comfort level your looking for.