The last time I trailered I had 2900# single axel trailer. It didn't take much more than my car jack to lift it. My "new" Formula 382 weighs around 15K wet on the steel trailer. I figured a 2 1/4 T floor jack would lift one wheel. I was wrong. It barely budged it. I looked into bottle jacks but I am concerned that with a flat tire the axel will be to low to use a normal 9" jack. What are you guys using?

Stack of nailed together 2 X 6's will allow you to drive the trailer up and take a wheel off the ground without a jack.

There is also a company that makes a composite "ramp" for that reason. You can also use a curb if you have to.

Thanks guys! That sounds a lot safer than a jack

How about throwing some sand on the ramp and laying a loose piece of wood on top to slide?

Driving on something is a good idea. Or you put wood or whatever under the wheel and let the air out, if all you doing is changing the tire. Lifting the boat/trailer in one spot may "bend" the frame.
Be carefull. I even changed tire on sand. Flat 2X6 under the wheels and just dug out the sand under the "flat" tire.

Good luck.

I like the sand solution

A 4500 pound jack should have picked up one wheel easily I would have thought given about 2500 pounds per wheel

I bought the jack at a Pep Boys going out of business sale. It was cheap. You get what you pay for. I am absolutely certain that you will bend the frame if you put a jack under one of the rails. I was trying to lift on the axel next to the shakle

take it to a truck stop with an 18 pack of budlite... instant tire change..

My immediate problem is that I have to put brakes and a controller on one of the axels before I can register (inspection by DMV required) the boat and trailer. I have a FWD duelly but I am not sure the grass offers enough traction to pull it up a ramp. Probably give it a try before I resort to jacks though