Quick answer
For riding-mower and tractor tires, our top pick is Slime 10008 (24 oz). It seals tread punctures up to ¼″, stops slow leaks, lasts up to 2 years and includes a valve-core tool. For bigger thorns and nails, FlatOut QuickStrike uses Kevlar fibers to seal up to ½″ for the life of the tire. If your mower has inner tubes, use a tube-rated sealant like Slime 2-in-1.
Mower tires pick up thorns, nails and sharp sticks, and low-pressure tubeless tires also leak at the bead. Sealant sits inside the tire, and when air escapes, the fibers are pushed into the hole and plug it. It works best when installed before a flat, and it won’t fix sidewall cuts or badly damaged tires.
| 1 |  | Slime 10008 Mower & ATV Sealant (24 oz)Best Overall | Check price |
| 2 |  | FlatOut Off-Road Multi-PurposeBest Long-Life Sealant | Check price |
| 3 |  | FlatOut QuickStrike Off-Road (32 oz)Best for Large Punctures | Check price |
| 4 |  | Slime 2-in-1 Tire & Tube Sealant (16 oz)Best for Tubed Tires | Check price |
| 5 |  | TireJect 5-in-1 Gallon KitBest for Bead Leaks and Dry Rot | Check price |
| 6 |  | Tusk First Line Sealant (32 oz)Best for Cold Climates | Check price |
The best lawn mower tire sealants
1Slime 10008 Mower & ATV Sealant (24 oz)Best Overall
Slime’s off-highway formula for tubeless tires. It seals tread punctures up to ¼″ (6 mm), stops slow leaks and protects for up to 2 years. It’s non-toxic, non-flammable and non-corrosive, and comes with a valve-core tool and hose.
- For: tubeless off-highway tires
- Seals: tread punctures up to ¼″
- Lasts: up to 2 years
- Includes: valve-core tool, hose
Best For: Riding mowers, lawn tractors and zero-turns.
Pros:
- Proven formula
- Easy install
- Water-soluble cleanup
Cons:
- ¼″ limit
- Reapply every ~2 years
2FlatOut Off-Road Multi-PurposeBest Long-Life Sealant
A Kevlar-fiber, latex-free formula for tubeless tires on ATVs, UTVs, golf carts and riding mowers. It’s water-washable and non-toxic, with an easy-install cap.
- For: tubeless tires
- Fiber: Kevlar
- Formula: latex/adhesive-free, water-washable
Best For: Landscapers and heavy-use mowers.
Pros:
- Kevlar fibers
- No sticky mess
- Trusted by pros
Cons:
- More expensive than Slime
3FlatOut QuickStrike Off-Road (32 oz)Best for Large Punctures
FlatOut’s faster-sealing formula. It’s a one-time application for the life of the tire, seals tread punctures up to ½″, and is listed for lawnmowers and ZTRs.
- For: tubeless off-road tires, mowers, ZTRs
- Seals: tread punctures up to ½″
- Lasts: life of the tire
- Fiber: Kevlar
Best For: Properties with thorns, nails or brush.
Pros:
- Seals bigger holes
- One-time install
- Fast sealing
Cons:
- Pricier per ounce
4Slime 2-in-1 Tire & Tube Sealant (16 oz)Best for Tubed Tires
Works in both tubeless tires (punctures up to ¼″) and inner tubes (up to ⅛″). Good for push mowers, wheelbarrows, small trailers and riders with tubes.
- For: tubes and tubeless tires
- Seals: ¼″ tires / ⅛″ tubes
- Size: 16 oz
Best For: Mowers with inner tubes or mixed equipment.
Pros:
- Works in tubes
- Cheap
- Includes tool and hose
Cons:
- Small bottle for big tires
5TireJect 5-in-1 Gallon KitBest for Bead Leaks and Dry Rot
A gallon kit with an injector tool, made with liquid rubber, recycled tire particles and aramid fibers. It’s listed to seal punctures up to ⅜″ in the tread and sidewall, plus bead leaks and minor dry rot, for a year per application.
- Seals: up to ⅜″, including sidewall
- Also: bead leaks, minor dry rot
- Lasts: about 1 year (reapply yearly)
- Size: 1 gallon + injector
Best For: Older tires that seep at the bead or crack.
Pros:
- Handles bead leaks
- Big kit for many tires
- Injector included
Cons:
- Yearly reapplication
- Expensive upfront
6Tusk First Line Sealant (32 oz)Best for Cold Climates
An aramid-fiber sealant that seals up to ½″ in tubeless tires and ⅛″ in tubes, with freeze protection to -35°F. It’s non-corrosive and water-washable.
- Seals: ½″ tubeless / ⅛″ tubed
- Freeze protection: to -35°F
- Fiber: aramid
Best For: Mowers stored in unheated sheds.
Pros:
- Freeze protection
- Large punctures
- Tube and tubeless
Cons:
- Balancing feature is aimed at faster vehicles
How to install tire sealant
1. Position the valve
Rotate the tire so the valve is at 4 or 8 o’clock, then let the air out.
2. Remove the core
Unscrew the valve core with the included tool.
3. Add sealant
Squeeze in the amount the label gives for your tire size (e.g. 4.80×8 or 20×8-8).
4. Reinflate and spin
Reinstall the core, inflate to the sidewall pressure and drive or roll the mower to spread the sealant.
Frequently asked questions
Does tire sealant work in lawn mower tires?
Yes. Low-pressure tubeless mower tires are ideal for it. It seals small tread punctures and slow leaks, especially when installed before a flat.
Can sealant fix a sidewall puncture?
Most can’t. TireJect claims small sidewall punctures up to ⅜″. Large cuts or tears need a new tire or tube.
Will tire sealant damage my rims?
The products here are listed as non-corrosive. Clean the sealant out when you change the tire.
Related: Best lawn tractors · Lawn mower lifts and jacks
How we chose: This is a researched guide. We compared rated puncture size, tube or tubeless use, longevity, freeze protection and installation from current product listings. We didn’t field-test these sealants.
Update log: November 2026: rebuilt the guide. We narrowed the list to six sealants for different needs, added tube vs tubeless guidance, install steps and an FAQ.