Best mod. to TT

JT Stabilizers

Best single all around mod: replaced the standard rv mattress.

I have done over two dozen (hum, maybe closer to 3 dozen) mods, from ~$1.00 stick-on clothes hangers to ~$2000.00 for double pane windows, all of which could qualify in some way to your request.
Each mod should have a reason for doing it (usually there are several). So what is it that you want to accomplish and how much are you willing to spend?

Steve

Pro-Pride hitch.

Solar

For reliability it was replacing all of the bushings, 14 in all, with oil-lite bronze bushings, grease-able pins and HD links. laying on rocks with snow flakes flying and reaming holes was not fun but you can't do these kind of repairs in the summer, that's camping time.
I had 18yrs on my TT when we got a 5er. No more worn links and pins. I'm trying Never Fail brand bushings in the 5er but it's to soon to give a thumbs up or down yet.