RENGASREPOPractical tyre intelligence
Maintenance & Storage4 min read2026-09-20AI-assisted

Tyre Storage Standards and Rubber Ageing

Clean tyres thoroughly before seasonal hibernation. Proper tyre stacking, UV protection, and the critical six-year rubber hardening timeline.

TYRE STORAGE & CARE
STORAGE POSITION & RETORQUE MANDATE

Why wheels on rims are stacked flat, loose tyres stand upright – and why 100 km retorque is non-negotiable

Wheel assemblies carry air pressure and rim weight: resting them flat or hanging prevents bead deformation. Tyres without rims must stand upright to prevent carcass ovality. And remember: every autumn, dozens of loose wheels fly off on motorways because drivers skip the mandatory 100 km bolt re-torque.

STORAGE POSITION

Mounted flat, unmounted upright

Wheels with rims are stacked flat or hung from the rim hole. Tyres without rims stand upright on the floor and are rotated monthly.

JACK PADS

Always use a slotted rubber pad

Bare steel jacks crush paint and rock sills, and can puncture EV battery packs. A slotted rubber pad distributes load safely.

COIN CHECK

2 € for winter, 1 € for summer

2 € outer ring is 4 mm (winter safe boundary). 1 € brass ring is 3 mm (summer wet grip recommendation; legal min 1.6 mm).

Storage Environment

Cool, Dark and Dry Storage to Protect Elasticity

Tyre rubber contains aromatic plasticizers that keep sipes supple even at −20 °C. Storing wheels in hot boiler rooms, under direct sunlight, or near ozone-generating electric motors evaporates these oils within two seasons. Keep tyres in a space below +15 °C away from moisture and oil spills.

Mounted on RimsStack flatHang on hookLoose Tyres (No Rims)Stand uprightDo not stackBeads collapse
Mounted on Wheels

Stack flat on their sides up to four high, or hang suspended through the centre hole. Do not stand mounted tyres upright for months, as weight causes flat spots.

Loose Tyres (No Rims)

Store standing upright side by side on a flat floor or tyre rack. Rotate them slightly every month. Never hang loose tyres from hooks, as it deforms beads.

The 6/10 Age Limit

Why a 10-year-old tyre is hazardous even with 8 mm of tread

“Traficomin ja rengasvalmistajien virallinen 6/10-suositus: rengasta saa käyttää enintään 6 vuotta käyttöönotosta ja sen kokonaisikä saa olla enintään 10 vuotta valmistusleimasta (DOT). Vuosien kuluessa kumin pehmittimet ja luonnonöljyt haihtuvat. Kumi muuttuu kovaksi kuin jääkiekon korppu. Vaikka renkaassa olisi uudenveroinen 8 mm urasyvyys, se ei jousta peilijäällä eikä pureudu asfalttiin, vaan jarrutusmatka tuplaantuu.”

Tip: Always check the 4-digit DOT stamping on the sidewall before purchasing used tyres online (e.g. '2422' = Week 24, Year 2022).

Safe DIY Wheel Swapping

Trolley Jacks, Jack Pads, and Correct Torque

Never change tyres on soft sand or an incline. Engage park or first gear and apply handbrake firmly. Loosen wheel bolts half a turn while wheels are on the ground. Position your trolley jack under designated factory lifting points using a slotted rubber pad. Tighten wheel bolts in a criss-cross star pattern with a torque wrench: 110–130 Nm for alloys, 100–120 Nm for steel rims.

Why the 100 km retorque is critical

Alloy wheels expand and contract with brake heat and road vibration. Any tiny speck of rust or grit between wheel hub and rim beds down during early driving, releasing bolt tension. A quick 2-minute torque wrench check prevents wheel loss.

Inspection & Coins

How to Measure Summer vs Winter Tread with Pocket Coins

Tread depth dictates water and slush evacuation. You do not need a professional gauge in your driveway—standard euro coins give instant visual thresholds for both seasons.

TALVIRENGAS (2 € TESTI)Raja: 4,0 mm

2-Euro Coin – 4 mm Silver Outer Edge

Insert a 2-euro coin into the main tread groove. The silver rim is exactly 4 mm wide. If the outer silver ring stays visible above the tread block, the tyre has less than 4 mm depth and slush resistance is depleted.

KESÄRENGAS (1 € TESTI)Suositus: 4,0 mm (Laki 1,6 mm)

1-Euro Coin – 3 mm Brass Outer Ring

Insert a 1-euro coin into the tyre groove. The gold/brass rim is 3 mm wide. While the legal minimum for summer is 1.6 mm, aquaplaning risk multiplies sharply below 3–4 mm in heavy summer showers.

Cleaning & Maintenance

Why Trapped Road Grit Damages Belts Over Storage

Rinse off corrosive winter road salts with mild car shampoo before storing. Use a flathead screwdriver or dull tool to gently pry out sharp crushed granite stones jammed between tread blocks. On the highway, every tyre revolution drives trapped sharp grit deeper, eventually perforating internal steel belts and causing slow air leaks.

Interactive Decoder

DOT Age Stamp Decoder

Type the 4 digits from your tyre sidewall (e.g. 2422)

DOT
Manufacturing DateWeek 24 / 2022
Current Rubber Age4 years old
Kettu Recommendation

Rubber compound is within prime elastic lifespan.

Scientific Sources & Data Provenance3 citations

Peer-reviewed studies, institutional tests, and official standards with DOIs and canonical URLs.