The Sea Ray 310 Sundancer 2013 vs Sea Ray Sundancer 400 1999 comparison sits squarely in the category of decisions where specs alone won't tell the whole story — intended use, storage, and long-term ownership costs all factor in.

Size is the most obvious dividing line here. The Sea Ray Sundancer 400 1999 measures 40,0 feet overall (1999), giving it roughly 9,0 additional feet of deck space compared to the Sea Ray 310 Sundancer 2013 at 31,0 feet (2013). Weight tells a clearer story for trailering families: the Sea Ray Sundancer 400 1999 tips the scales at 22 500 lbs — 21 337 lbs less than the Sea Ray 310 Sundancer 2013 at 1 163 lbs. That difference is meaningful if you're working within a half-ton or three-quarter-ton truck's tow rating, especially once you factor in a motor, gear, and fuel.

The power gap is worth calling out. Rated to 383 hp, the Sea Ray Sundancer 400 1999 has a 163-hp advantage over the Sea Ray 310 Sundancer 2013's 220-hp ceiling — enough to notice on acceleration and at cruising speed, particularly with a full passenger load. Fuel capacity breaks the other way: the Sea Ray Sundancer 400 1999 carries 335 gallons versus 125 gallons in the Sea Ray 310 Sundancer 2013. On a lake day that's negligible, but for coastal cruising or long reservoir runs the extra range matters.

For family outings this is probably the sharpest distinction between the two. The Sea Ray Sundancer 400 1999 is rated for 12 passengers, while the Sea Ray 310 Sundancer 2013 caps at 9. If you're regularly pulling extended family or a group of friends onto the water, the extra seats on the Sea Ray Sundancer 400 1999 could be the deciding factor.