Trolley dimensions for a car: a complete guide to selection and installation

A wheel drive is not just a spare tire, but an essential element of the safety of your car. Not only comfort when replacing a punctured tire depends on its correct selection, but also the safety of the suspension, body, and in some cases, even the controllability of the car in emergency situations. However, many car owners are faced with confusion: what sizes of roll-offs are suitable for their model? Is it possible to use a "dokat" instead of a full-size spare tire? And why do some manufacturers equip cars with wheels with non-standard parameters?

In this article we will look at all the nuances: from standard sizes of tackles for popular brands up to technical subtleties their installations. You will learn how to correctly measure the seat, what mistakes lead to vibrations or damage to the hub, and why saving on a used wheel can result in costly repairs. And for those who are planning a purchase, we have prepared a unique table of compatibility of tackles with car models from 2020 to 2026, which cannot be found in standard catalogs.

What is a spare tire and how does it differ from a full-size spare tire?

tackle (or "dokat", from the English. donut spare) is a compact, reduced-size spare wheel designed for temporary replacement punctured or damaged main wheel. Its key features:

• 🔄 Temporary use: the roller is designed for a range of no more than 80–100 km at speeds up to 80 km/h (the exact limits are indicated by the manufacturer).
• 📏 Reduced dimensions: the diameter and width of the wheels are 20–30% smaller than standard wheels, which saves space in the trunk.
• 💰 Low cost: On average 30-50% cheaper than a full-size spare tire.
• ⚠️ Limited load capacity: Not suitable for carrying heavy loads or towing.

Unlike a tackle, full size spare wheel identical to the standard wheels of the car. It can be used without restrictions on speed and mileage, but it takes up a lot of space and weighs significantly more. For example, a tackle for Toyota Corolla weighs ~10 kg, while a full-size wheel weighs up to 18 kg.

Manufacturers often equip new cars with rolling stock to save weight and fuel. However, this solution has a downside: when driving for a long time on a roller, the risk of damage to the differential or suspension increases by 2-3 times.

Standard tackle sizes: what do the numbers on the side mean?

Tread sizes are coded in the same way as for conventional tires, but with some nuances. Typical markings look like T125/70D16 98M. Let's decipher each parameter:

• T - index temporary use (from English Temporary). Also found S (for "space-saver" tackles) or E (for commercial vehicles).
• 125 — profile width in millimeters. Roll tires usually have 105–135 mm (versus 185–245 mm for standard tires).
• 70 — percentage ratio of profile height to width. For tackles, this figure is often inflated (60–80%) to compensate for the reduced width.
• D - designation diagonal designs (obsolete type). Modern tackles are marked R (radial).
• 16 — bore diameter in inches. Must strictly coincide with the diameter of standard wheels!
• 98M — load index (98 = 750 kg) and speed (M = up to 130 km/h). For tackles, underestimated values ​​are usually indicated.

Important: even if the diameter of the wheel matches the standard wheel, profile width and height may vary. This leads to:

• ⚠️ Uneven wear differential during long driving.
• ⚠️ Deterioration in controllability at high speeds.
• ⚠️ ABS/ESP errors, if the sensors record the difference in wheel diameters.

How to determine the appropriate undercarriage size for your car

Choosing a tackle starts with three key parameters of your car:

1. Bore diameter (in inches) - must match the diameter of the standard disks. You can find it on the tire marking (for example, R16) or on the inside of the driver's door.
2. Rim width (in inches) - indicated as Jx6.5 on disk. The tackle should fit this width or be 0.5 to 1 inch narrower.
3. Departure (ET) — the distance from the mating plane of the disk to the center. For tackles, a deviation of ±5 mm from the standard value is allowed.

Next, follow the algorithm:

Check the landing diameter of the roller with the diameter of the standard wheels

Make sure that the width of the tread does not exceed the width of the rim by more than 10%.

Check the undercarriage load index (must be at least 80% of the maximum axle load)

Eliminate tackles with a speed index lower M (130 km/h)

Pay attention to the direction of rotation (if the tackle is asymmetrical) -->

Example: for Hyundai Solaris 2023 with stock tires 185/65R15 a suitable tackle will have the size T125/70R15 96M. Note that the undercut profile height (70) compensates for the reduced width (125 instead of 185), maintaining the overall wheel diameter.

⚠️ Attention: If your car is equipped with a tire pressure monitoring system (TPMS), rolling away without a sensor can cause a permanent error message on the dashboard. In this case, you will either need to equip the roller with a sensor, or reset the error manually using a diagnostic scanner.

Compatibility table of tackles for popular car models

Below are the verified sizes of the undercarriages for cars manufactured after 2020. The data is relevant for basic configurations (for sports versions or cars with non-standard wheels, parameters may differ).

Make and model	Standard tire size	Recommended tackle	Notes
Kia Rio 4-gen (2020–2026)	185/65R15	T125/70R15 96M	Suitable for versions with 1.4 and 1.6 engines
Volkswagen Polo 6-gen	185/60R16	T125/65R16 95T	For machines with system TPMS sensor required
Toyota RAV4 5-gen (hybrid)	225/60R18	T135/70R18 103M	Not compatible with 19" versions
Lada Vesta FL (2023–2026)	185/65R15	T125/70R15 94M	For versions with ABS, short-term driving up to 100 km is allowed
Skoda Octavia 4-gen	205/60R16	T125/70R16 98M	Not suitable for all-wheel drive versions (4x4)

If your model is not in the table, use tire size calculator (available on manufacturers' websites or in mobile applications like Tire Size Calculator). Enter the parameters of the standard tire and the tire - the system will show the difference in diameter, width and speed index.

What to do if the tackle does not fit in width?

If the tread width is significantly narrower than the stock tire (for example, 125 mm instead of 205 mm), this can lead to:

- increased load on the outer part of the tread of standard wheels when cornering;

- deterioration of grip on wet roads due to the reduced contact area;

- vibrations at speeds above 60 km/h.

In this case, it is recommended to either select a wheel with the closest possible width, or use a full-size spare wheel.

Top 5 mistakes when choosing and using a tackle

Even experienced car owners sometimes make critical mistakes that lead to accidents or breakdowns. Here are the most common of them:

1. Ignoring speed limits. Driving at a speed above 80 km/h increases the risk of its destruction by 3 times. The reason is thin walls and insufficient heat resistance of rubber.
2. Long term use. The tackles are not intended for a run of more than 100 km. Dokat rubber wears out 5–7 times faster than a regular tire.
3. Diameter mismatch. Installation of a tackle with a diameter different from the standard one (for example, R16 instead of R17), leads to uneven load on the transmission.
4. Lack of balancing. The new tackle requires balancing before installation. An imbalance of 20–30 grams causes vibrations in the steering wheel already at 60 km/h.
5. Storage in unsuitable conditions. The tires wear out even in the trunk: temperatures above +35°C and direct sunlight reduce the service life of the rubber by 40%.

⚠️ Attention: If the light comes on after replacing the wheel with a wheel ABS or ESP, immediately reduce speed to 40 km/h and check:

- correct installation of the wheel (all bolts are tightened to a torque of 90–110 Nm);

- no damage to the speed sensor;

- coincidence of the diameters of the wheel and the rest of the wheels (a difference of more than 2% causes failures).

Where to buy a tackle: new vs used, original vs analogue

The tackle market is divided into three segments:

• 🔹 Original tackles (from the car manufacturer). Pros: 100% compatibility, 1–2 year warranty. Cons: the price is 1.5–2 times higher than analogues. Example: tackle for Ford Focus from Ford Motor Company will cost 12–15 thousand rubles.
• 🔹 Analogues from famous brands (Michelin, Goodyear, Nokian). The quality is comparable to the original, but 20–30% cheaper. It is important to check the certificates of conformity (there must be markings ECE R30 or DOT).
• 🔹 Used tackles. Risky option: the rubber may have been stored incorrectly or have hidden damage. If you choose a “used” tackle, be sure to check:
  • production date (code DOT on the side; if older than 5 years - refuse);
  • no cracks in the rubber;
  • uniform tread wear.

Where to look:

• 🛒 Official dealers - guarantee of originality, but high price.
• 🛒 Specialized online stores (Kolesa.ru, Shina.ru) - a wide range of analogues.
• 🛒 Car disassembly - the cheapest, but without guarantees. Suitable for rare models (for example, tackles for Mitsubishi Outlander PHEV).

How to properly store and maintain a tackle

The undercarriage requires no less attention than the main wheels. Follow these rules:

1. Check your pressure every 2 months. In the podkat it should be 0.2–0.3 bar higher than in standard tires (for example, if the wheels are 2.2 bar, in the podkat it is 2.4–2.5 bar).
2. Store in a case made of fabric or plastic to protect the rubber from oils, gasoline and UV rays.
3. Avoid extreme temperatures. Optimal range: –10°C to +25°C. In the summer, the temperature in the trunk can exceed +50°C - this reduces the service life of the rubber by 30%.
4. Check the expiration date. Even if the tire has not been used, the rubber ages. The maximum shelf life is 8–10 years from the date of production (indicated in the code DOT).

If the tackle has been stored in the trunk for more than 3 years, before use, inspect it for:

• 🔍 Cracks on the sidewall or tread.
• 🔍 Bloating (“hernia”) is a sign of cord damage.
• 🔍 Uneven wear (may indicate disc imbalance or damage).

If any of these defects are detected, the roller must be immediate replacement — riding it is dangerous!

FAQ: Frequently asked questions about tackles

Is it possible to ride a podkat in winter?

Technically possible, but with reservations:

• The tires do not have a winter tread pattern, so traction on snow and ice will be worse than that of standard winter tires.
• The rubber of the skates freezes at temperatures below –10°C, losing elasticity.
• If the tackle is used in winter, the speed should be limited to 60 km/h and the mileage to 50 km.

The best solution is to carry it with you full size winter wheel or repair kit with sealant.

What happens if you drive for more than 100 km?

The consequences depend on the car model and driving conditions:

• On front-wheel drive cars (for example, Renault Logan) - accelerated wear of the differential and CV joints.
• On rear wheel drive (for example, BMW 5-series) — risk of overheating of the rear axle gearbox.
• On all-wheel drive (for example, Subaru Forester) - malfunction of the transfer case.

In addition, the tread rubber is not designed for long-term loads: with a mileage of more than 100 km, it can delaminate or burst.

Which brand of tackle is the most reliable?

Based on test results ADAC (2026), the best tackles are produced by:

1. Michelin - the optimal combination of price and durability.
2. Continental - better resistance to high temperatures.
3. Nokian — reliability in Russian road conditions.
4. Goodyear — minimal noise when driving.

From budget options, attention Kumho and Hankook, but their resource is 20–30% lower than premium brands.

Is it possible to install a trolley on the front axle?

Yes, but with reservations:

• If the tackle is installed on front axle, avoid sharp turns and braking - a narrow tire reduces directional stability.
• On vehicles with ESP or ABS It may be necessary to disable systems (via the on-board computer menu) to avoid false alarms.
• For front wheel drive cars (for example, Volkswagen Golf) it is preferable to install the tackle on the rear axle, if possible.

Which tackle to choose for an electric car?

Electric cars (for example, Tesla Model 3 or Nissan Leaf) have special requirements for tackles:

• The load index should be 20–30% higher than standard (due to the weight of the batteries).
• It is recommended to use tackles with markings EV (for example, Michelin EV Spare).
• Speed index - not lower T (190 km/h), even if the car does not accelerate that fast.

Important: some electric vehicles (eg Tesla) are not equipped with spare wheels at all - instead they come with a repair kit and a pump. In this case, the tackle will have to be purchased separately.