Lake of the Ozarks · Pontoon and Tritoon Lifts

You upsized to a tritoon and kept the pontoon lift. The middle tube is carrying nothing.

A pontoon lift has 2 bunk pairs, one under each outer tube. A tritoon has three tubes. The math does not work, and the boat tells you eventually.

Call (573) 410-3050or request a callback below

Answer first: Boat Dock Repair Osage Beach works pontoon and tritoon lifts across the lake. A pontoon lift carries 2 bunk pairs, one per outer tube. A tritoon needs a third pair under the center tube, and running one without it either leaves that tube unsupported or lets a deck crossmember bear on it. Adding a bunk pair is normally a parts-and-labor job on the lift you already own. Where it stops being that is capacity: a tritoon is usually heavier than the pontoon it replaced, and if the loaded boat is over the lift rating, more bunks will not save it.

Why a pontoon lift is not a boat lift with a different sticker

A V-hull sits into a cradle and finds its own center. A pontoon does not. It rides on 2 or 3 parallel tubes with a flat deck bridging them, and it needs support along the length of those tubes rather than under a keel. That drives a genuinely different lift: wider and longer in the frame, with bunks that run fore and aft under each tube the way trailer bunks do, and enough beam to hold a modern pontoon that is far wider than the ones these lifts were sized for a decade ago.

Bunk-style support is the stable answer for the same reason a trailer uses it. Load spreads along the tube instead of concentrating at a point, and the boat is held against side-to-side movement. That matters more here than on a protected lake. Cruiser wake through a cove works a pontoon sideways on its lift all summer, and a boat sitting on inadequate support moves a little every time.

The tritoon problem, specifically

Tritoons became normal on this lake fast, and plenty of them landed on lifts bought for a two-tube boat. The failure is not dramatic. It is a center tube with nothing under it, or a lift relying on deck contact that ends up bearing on that middle tube instead of the frame around it. Either way the load is going somewhere it was not designed to go.

The fix is usually a 3rd bunk pair set to the center tube, sized and positioned to that specific boat. That is a real job but a normal one, and it is far cheaper than the alternative people reach for, which is replacing a lift that was structurally fine and only ever needed the right cradle configuration.

What we find on pontoon lift calls

Pontoon and tritoon lift symptoms and usual causes
What you noticeUsual causeFix
Boat sits crooked, one tube lowerFlattened or shifted bunk on that side, or uneven cable take-upBunk replacement or cable adjustment
Center tube scuffed or dented on a tritoonDeck crossmember bearing on the middle tube with no bunk under itAdd the 3rd bunk pair, reset contact points
Lift labors or trips on the way upLoaded boat at or past lift capacity, common after a pontoon to tritoon upgradeReal weight check, then a capacity conversation
Bunk carpet gone, wood showingOrdinary wear, accelerated by wake movementRe-carpet or replace bunks before the tube gets marked
Boat shifts on the lift through the seasonBunks too short or set wide of the tube centerlineReposition to the boat, not to the previous boat

Capacity, honestly

The number that matters is the loaded boat, not the brochure. A tritoon usually carries more tube, more deck, and a bigger engine than the pontoon it replaced, and owners rarely re-check the lift when they trade up. A lift run at or beyond its rating does not fail all at once. Bunks flatten, cables give at the drum, and the mounts start working, and by the time anyone calls it has been overloaded for a 2 or 3 seasons. Getting the real weight takes one conversation and it changes what we recommend.

If the lift genuinely is undersized, we say so rather than selling bunk work that will not hold. For scale: bunk and adjustment work commonly lands $200 to $500, while a full lift replacement runs $1,000 to $8,000 and up by capacity, which is why adding a 3rd bunk pair to a sound frame is usually the better spend by a wide margin. Ranges for lift work live in the cost guide, and a written number comes before anything starts. Cable and cradle wear usually arrive together, so cable condition gets checked on the same visit.

On this lake specifically

Almost every dock here floats, because Ameren draws the lake down about 6 feet each winter and a fixed structure would tear itself apart. So a pontoon lift is normally mounted to a dock that moves. That is fine, and it is the right pattern, but it means the lift and the dock share every load between them. A pontoon that shifts on worn bunks all season is putting that movement into the dock frame too, which is why we look at both. If the dock itself is listing, the lift will look broken when it is not, and that is a float problem rather than a lift problem. Larger multi-tube lifts are common in the deeper coves and around the Village of Four Seasons, and they price toward the top of the range by capacity.

Get the pontoon lift looked at

Two fields. We call you back and talk through what the lift is doing.

Spring and post-storm weeks get busy. Calling always beats the form.

Frequently asked

I bought a tritoon and kept the old pontoon lift. Is that a problem?
Usually yes, and it is the single most common pontoon lift mistake we see. A pontoon bunk lift carries 2 bunk pairs, one under each outer tube. A tritoon has a third tube down the middle, and on that lift it is carrying nothing. The center tube either hangs unsupported or takes contact from a deck-style crossmember that was never meant to bear on it. A 3rd bunk pair is the fix.
Does a tritoon weigh enough more to need a bigger lift?
Generally yes. A tritoon carries a third tube, usually more deck, and often a much larger engine than the pontoon it replaced, so owners upsizing from one to the other regularly land over the old lift capacity without realising it. Weigh the real loaded boat before assuming the existing lift covers it. Running a lift at or past its rating is how bunks flatten and cables go early.
Should the lift support the tubes or the deck?
Tubes, through bunks, in almost every case. Bunks spread the load along the tube the way trailer bunks do and keep the boat stable side to side. Lifting on the deck concentrates load into deck framing that was not designed as a lifting point, and on a tritoon it is also what leads to a crossmember bearing on the center tube.
My pontoon sits crooked on the lift. Is the lift bent?
Not usually. Start with the bunks. Flattened or shifted bunks on one side drop that tube lower and the whole boat looks racked. Uneven cable take-up does the same thing and is the other common cause. A genuinely bent frame is real but rarer, and it normally comes with a story attached, an ice season or a hard grounding.
Dock going down right now?
A sinking corner takes the lift and boat with it. Call. The phone is answered around the clock in season.
Call (573) 410-3050