Not sure what the weight of my boat is, but it's not light and pushes the limits of what I'd pull with my ST. Regardless, I have no troubles what-so-ever pulling my boat out of the ramp with my 2WD. However, I also make note of the good ramps to use. Like Bill said, if it's steep and not used a lot (lots of algea and growth), or it's low tide (if there are tides), then the variables start working against you. Just use your good judgement. Don't slam on the gas, just ease it out and it should be fine. Maybe even have someone sit on your tailgate if you're really worried.
My 20.5' Wellcraft.
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