A common failure area for travel trailers is the suspension. Broken shackles, leaf springs, hangers etc. From the factory our RV had a standard equalizer and shackles with nylon bushings. I installed much stronger shackles with bronze bushings and grease-able wet bolts. I also changed our traditional equalizer to a MORryde CRE3000. To further improve ride and help the leaf springs I added trailer SumoSprings. I used the TSS-107-40 with my 4.4k axles, which are recommended for GAWR of 3k-5k pounds. I may add a spare leaf spring or two to the parts kit. Reinforcing the hangers would be the final step but requires welding which is not currently in my DIY tool kit.
MORryde has a qualification guide to see if their equalizer will work with your trailer.
Tires are a hot topic for RVs. I had China sourced LionsHead Castle Rock tires on our RV. We put 9,000 miles on them in the first three seasons with no trouble. I did have a tire monitoring system that let me keep track of pressure and temp. Before our trip out west in 2023 I replaced them with Goodyear Endurance tires. They are made in the USA, have a higher speed and load rating, and have a good reputation for reliability.
LionsHead Castle Rock ST225/75R15 | Load Range D | Max Speed 75mph | 2540lb @ 65psi | Made in China
Goodyear Endurance ST225/75R15 | Load Range E | Max Speed 87mph | 2830lb @ 80psi or 2540lb @ 65psi | Made in USA