1956 MG Tire Fitment Guide

1956 MG vehicles use three tire sizes across four model lines: 155R15, 560-15, and 550-15. The 155R15 radial size is shared by the MG, MGA, Magnette, and Midget, while 560-15 bias-ply fits the MG and MGA, and 550-15 bias-ply fits the Magnette and Midget. All three sizes mount on 15-inch wheels. Published rim-width ranges include 4.00 to 5.50 inches for 155R15, 4.5 inches or 4.50 to 5.50 inches for 560-15 depending on product, and 3.00 to 3.50 inches for 550-15.

That means year and make alone are not enough to choose correctly if you want a bias-ply tire, because the saloon and smaller-car fitments differ from the sports-car fitment. The shared 155R15 radial gives all four models a common option, but wheel width still needs to be checked against the actual tire you choose. Start with the model, confirm the wheel diameter is 15 inches, and then match the tire to the rim-width range listed for that specific product.

On a 1956 MG, 155R15 is a metric radial size. The 155 identifies a nominal section width of 155 millimeters, the R indicates radial construction, and the 15 is the wheel diameter in inches. In period-style metric sizing like this, the aspect ratio is not written out, but it is conventionally treated as an 80-series radial. Available versions include blackwall tires from Firestone and Michelin, with both tube-type and tubeless examples in the range.

That decoding matters because 155R15 is the one size that crosses the entire 1956 MG lineup, from sports cars to the Magnette and Midget entries listed here. It is also the size with the most variation in product character, including different speed ratings and tube markings. If you want the broadest radial choice for a 1956 MG, this is the place to focus, but you should still compare the exact sidewall marking and rim-width suitability before settling on one tire.

No, not all 1956 MG models use the same tire size. Every model in the range can use 155R15 radial tires, but the bias-ply options divide by model: 560-15 belongs to the MG and MGA, while 550-15 belongs to the Magnette and Midget. All of them use 15-inch wheel diameters, so the split is not about rim diameter as much as it is about selecting the proper size family for the specific model.

That distinction is especially important for restorations and for owners trying to preserve the original look and stance of a particular MG model. A buyer shopping by year alone might assume all mid-1950s MGs used the same numeric bias-ply size, but that is not the case here. If your car is a Magnette or Midget, start with 550-15 when considering bias-ply options; if it is an MG or MGA, start with 560-15.

For a 1956 MG or 1956 MG MGA, the choice between 155R15 and 560-15 is largely a choice between radial and bias-ply construction rather than a change in wheel diameter, since both fit 15-inch rims. The 155R15 is a radial available in blackwall form from Firestone and Michelin, while 560-15 is a bias-ply size available from Firestone and US Royal with narrow whitewall and wide whitewall styles. The radial range also includes different speed ratings and both TT and TL markings depending on the product.

Choose 560-15 if the goal is to preserve an unmistakably mid-1950s appearance and bias-ply road feel on an MG or MGA. Choose 155R15 if you want a radial alternative that still stays within an appropriate 15-inch size family for the car. The better path depends less on outright fitment than on how you intend to use the car and how strictly you want to hold to period construction and sidewall style.

1956 MG tire sidewall choices vary by size. The 155R15 radial offerings are blackwall only, the 550-15 bias-ply option is also blackwall, and the 560-15 bias-ply size is available in both narrow whitewall and wide whitewall styles. Those whitewall choices come from Firestone and US Royal in the 560-15 size, while the blackwall radial and blackwall 550-15 options support a more understated look.

For many British sports-car restorations of the period, blackwall tires usually align more naturally with the restrained factory appearance enthusiasts expect to see, while whitewalls create a more stylized look. That makes sidewall style as much an authenticity decision as a design preference. If your 1956 MG is being judged or restored to a market-specific standard, compare your chosen sidewall to period photos and consult marque sources before finalizing the look.

Four brands appear in the 1956 MG tire range: Firestone, Michelin, US Royal, and Excelsior. Firestone and Michelin cover the 155R15 radial size, Firestone and US Royal cover the 560-15 bias-ply size, and Excelsior covers the 550-15 bias-ply size. Brand choice therefore depends partly on which MG model you have and partly on whether you are staying with a model-specific bias-ply size or moving to the shared 155R15 radial.

That brand spread gives MG owners different ways to approach the same year and make. A driver-focused owner may spend more time comparing the Michelin and Firestone radial offerings in 155R15, while a restoration-minded MG or MGA owner may focus on Firestone or US Royal bias-ply whitewall options in 560-15. The right comparison starts with the size that actually belongs to your model, then narrows by sidewall appearance and construction.

Rim-width guidance for 1956 MG tires depends on the size. The 155R15 radial range includes products suited to 4.00 to 5.50-inch rims. The 560-15 bias-ply products list either a 4.5-inch rim or a 4.50 to 5.50-inch range, depending on brand. The 550-15 bias-ply option is much narrower, with a listed rim-width range of 3.00 to 3.50 inches.

That spread matters because the entire 1956 MG lineup uses 15-inch wheel diameters, so width is often the deciding wheel question. A tire may share the right diameter yet still be wrong for the wheel if the rim is too narrow or too wide for the specific product. Measure the wheel you actually have, especially on a car with replacement rims or an older restoration, and match it against the stated range for the exact tire under consideration.

Inner-tube requirements on 1956 MG tires depend on the exact product and size. Within 155R15, tube status varies by product: Michelin X is marked TL, Michelin XAS is marked TT, and Michelin XAS-FF is marked TL, while the Firestone 155R15 listing does not add a TT or TL marker in the size description. The 560-15 and 550-15 listings are bias-ply products without TT or TL markers shown in the size field here.

The practical takeaway is to check the actual sidewall marking and the wheel type before installation rather than assuming all tires in the same size work the same way. Tube decisions can also be influenced by the wheel's original design and condition, especially on older British wheels. If your 1956 MG still uses original wheels or older restored rims, have the tire and wheel evaluated together so the tube setup matches both pieces correctly.

All of the tire sizes used on 1956 MG vehicles here are built around a 15-inch rim diameter, so original 15-inch wheels remain the common starting point across the range. That said, the sizes do not all share the same rim-width requirements. The 155R15 radial range suits 4.00 to 5.50-inch rims, 560-15 bias-ply products span 4.5 inches or 4.50 to 5.50 inches, and 550-15 fits a narrower 3.00 to 3.50-inch rim range.

So the answer is often yes on diameter, but not automatically yes on width. A sports-car wheel intended for 560-15 fitment is not the same setup as the narrower wheel range associated with 550-15. If your 1956 MG has been restored, swapped, or converted over the years, confirm both diameter and measured rim width before moving between the shared radial size and the model-specific bias-ply sizes.

A 1956 MG should be stored in a cool, dry, dark place away from direct sunlight, electric motors, battery chargers, welders, and other ozone sources that age rubber. Keep the tires clean, maintain inflation, and move the car periodically so it does not sit on one contact patch for months at a time. Bias-ply tires such as 560-15 and 550-15 tend to flat-spot more readily during long static storage than the 155R15 radial options, so they benefit especially from periodic movement or the use of stands.

Collector cars are often driven too little rather than too much, and storage habits can shape tire condition more than mileage does. If your 1956 MG spends winters or long stretches parked, make tire care part of the storage plan instead of treating it as an afterthought. Good storage preserves sidewalls, reduces set-up vibration on the first drive, and helps you catch aging problems before they turn into a roadside issue.

Tires on a 1956 MG should be judged more by age and condition than by miles driven. A sound rule for collector cars is to begin evaluating tires closely once they reach roughly five to seven years of age and to treat the ten-year mark as a strong point for replacement consideration, even if the tread still looks serviceable. The DOT date code on the tire sidewall is the starting point for that age check, whether the tire is a 155R15 radial or a bias-ply 560-15 or 550-15.

Many MGs see occasional fair-weather use, so a tire can age out long before it wears out. Sidewall cracking, hardening rubber, vibration, or persistent air loss matter more than odometer readings on a car like this. When a 1956 MG is driven only seasonally, setting a yearly inspection date tied to the tire's age helps you decide on replacement before a long tour or event rather than after a failure starts developing.

Tires on a 1956 MG should be inspected before every drive, and they deserve a more careful look before any longer outing. Check inflation, tread wear, weather checking, cuts, bulges, and any sign that the tire is no longer holding shape or pressure properly. On a car using tube-type tires or wheels that may require tubes, valve stems and any signs of leakage around the stem area deserve the same attention as the tread and sidewalls.

Frequent inspection matters because collector cars often sit for weeks between drives, and problems can appear while the car is parked rather than while it is being used. A quick walk-around can catch a low tire, cracked sidewall, or aging valve stem before it turns into heat build-up on the road. For a 1956 MG, that simple routine is one of the easiest ways to protect both the tires and the car.

For a 1956 MG MGA, bias-ply construction is the historically appropriate starting point for original-era fitment, and the model-specific bias-ply size in this range is 560-15. Radial options in 155R15 are also available today and fit the MGA's 15-inch wheel diameter, but they represent a later construction choice rather than the baseline mid-1950s norm. No original-equipment brand should be assumed from the current tire selection alone.

That means a factory-style restoration usually begins with 560-15 bias-ply tires and then narrows by sidewall appearance. If you are restoring a car for marque judging, period photos, factory literature, and MG club guidance are the right next steps for confirming market-specific sidewall expectations. A radial can still be a sensible choice for use, but it changes the construction story of the car even if the wheel diameter remains correct.

Correct tire fitment matters on a 1956 MG because judging standards often consider size, construction type, and sidewall appearance as part of the car's overall authenticity. A 560-15 or 550-15 bias-ply tire generally aligns more closely with mid-1950s expectations than a later-style radial, and a sidewall treatment that looks out of place for the model or market can stand out quickly. The specific standard, however, depends on the event and the club applying it.

That makes tires one of the most visible finishing details on a show car. Even when the wheel diameter is right, judges and knowledgeable enthusiasts may notice if the car carries a modern radial profile or a whitewall treatment that does not suit the restoration's theme. Before showing a 1956 MG seriously, compare your tires against event guidance and marque-club references so the final presentation matches the standard you are aiming for.

For a 1956 MG running 155R15 radials, the Michelin XAS and Michelin XAS-FF are both H-rated 155HR15 tires with 82 load index markings, blackwall styling, 15-inch rim diameter, and a 4.00 to 5.50-inch rim-width range. The key difference in the available listings is tube designation: the Michelin XAS is marked TT, while the Michelin XAS-FF is marked TL. Both sit above the T-rated Michelin X in speed category, with an H rating corresponding to 130 mph.

That makes the comparison less about overall size and more about the details of how the tire is set up on the wheel. Owners choosing between the two should look closely at the wheel type on the car and the sidewall markings on the tire they intend to use. For a 1956 MG, this is a good example of why two tires in the same nominal size can still call for different installation planning.

1956 MG tires can be suitable for highway use when the tire's condition, construction, and speed rating align with how the car is being driven. In the 155R15 radial size, available speed ratings include T at 118 mph and H at 130 mph on certain Michelin products. The 560-15 and 550-15 bias-ply options do not list speed letters here, so they should be approached with the understanding that tire construction and the car's mid-1950s mechanical character both shape sensible road use.

On a well-sorted MG, the tire is only one part of highway safety. Brakes, steering, suspension, alignment, and wheel condition often matter just as much on a vintage British car as the tire's top-speed category. For most normal cruising, the practical question is whether the tires are fresh, correctly inflated, and suited to the car's intended use rather than whether the printed rating exceeds what the car would realistically ever be asked to do.

Inflation pressure for a 1956 MG should not be copied from one tire size to another without checking the exact tire and the vehicle's original guidance. Among the available products here, 155R15 Firestone F560 shows a maximum load of 1045 pounds at 44 psi, while 560-15 bias-ply products from Firestone and US Royal show 970 pounds at 32 psi. Those figures describe the tire's rated capacity at a stated pressure, not automatically the factory operating pressure for every 1956 MG application.

Use the owner's manual or period service literature as the first reference for vehicle operating pressure, then compare that with the tire manufacturer's marking and recommendations for the reproduction or radial tire you have selected. A Magnette, Midget, MG, and MGA should not all be assumed to want the same setting simply because they share a 15-inch wheel diameter somewhere in the range. Pressure is one of the easiest places to make a small mistake that affects ride and wear.

Before a longer drive in a 1956 MG, inspect each tire for cracking, cuts, bulges, uneven wear, and proper inflation, and do not forget to check the spare. If the car uses tube-type tires or a wheel setup that requires tubes, inspect valve stems carefully and watch for slow leakage. A quick look at tread depth, wheel security, and how long the tires have been on the car belongs on the same checklist.

A longer trip is also the right time to think beyond the tires, because an MG from 1956 relies on the whole chassis and braking system being in equally good shape. Fresh rubber cannot compensate for loose steering, weak dampers, or neglected wheel bearings. Treat the tires as the first checkpoint in a broader pre-drive inspection, especially if the car has been sitting or if its last outing was many months ago.