Here's a snippet from my thread on tandem trailer blowouts:
Weight of Ford Excursion Diesel Tow vehicle #7120
Total Weight of TC 255, 3/4 fuel/water, no people but all accessories including trailer #10280
Trailer Weight Empty #1900
Boat Alone (do the math...) #8380
Tongue Weight #1280
Boat was 8380. I wouldn't use an 8000# lift. Mine is 10K.
Charlie