My old trailer with the floating problem had two axles. It had 16" tires on it too which adds to buoyancy compared to 15". Also, the trailer fenders could be trapping air in them as you back down the ramp. You can drill a couple of holes in top side just in front of the front axle to let the air escape.

I rebuilt my floating Rocket including adding 2nd axle brakes, new axles, longer bunks, and additional V-shaped bunks, and I was able to remove 2 of the 50 lb. dumbbells.

I had a 3 axle McClain aluminum I-beam trailer that did not float. I now have a Myco aluminum C-channel trailer that does not float.

Almost all trailers are made with just pine on them. I replaced all the wood on my used Myco when I bought it, and found out it was just plain old pine, not even pressure treated, and this REALLY disappointed me. The trailer was only 4 years old and the wood was in terrible, terrible shape. I replaced it with all pressure treated Pine bought from Lowes. Another OSO member in NC actually owns a Cypress sawmill, and I called him to buy new bunk wood. He told me to just go with PT pine, and as long the wood is solid, not cracked or terrible grade, it will last as long as cypress.

Just remember any of those home-made weight things become projectiles in a sudden stop or front impact. If your filling slick PVC with concrete and "strapping" them to a trailer they will not stay with the trailer in an accident.

I'd sure consider low profile tires, steel rims instead of aluminum, heavier bunks, eliminating air pockets or something to change to make the trailer heavier in a safer fashion.

I U-bolted the dumbells on. They were not coming off.

Easy,
Get a 195 plus lb., fat chick, that can hold her breath long enough to get your boat loaded.

Doesn't someone make a solid PVC bunk? I thought I saw it here a few years back.
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