Mickey Thompson Street Comp GHT - 255/45R18 103Y XL -277882

Next-Generation Ultra Ultra High Performance Summer Grip for High-Horsepower Builds

The Mickey Thompson Street Comp GHT in 255/45R18 (103Y XL) is built for the demands of high-horsepower American muscle on the street. The Street Comp GHT brings a new tier of Ultra Ultra High Performance (UUHP) engineering to sizes spanning 17 through 20 inches, featuring an advanced resin and silica-blended compound, an aggressive asymmetric tread design, and a lightweight reinforced internal structure engineered for high-speed stability and precision cornering. Material number 277882, the MTT321 series delivers confident grip on both wet and dry pavement without sacrificing street manners.

Key Features

• Ultra Ultra High Performance (UUHP) summer compound engineered for high-horsepower muscle and sports cars
• Advanced resin and silica-blended tread compound for superior wet performance and cornering control
• Aggressive asymmetric tread design channels water away while enhancing dry traction and reducing road noise
• Lightweight construction and aerodynamic profile improves steering response and reduces rotational drag
• Reinforced internal structure for high-speed stability and consistent handling
• UTQG 300 AA A rating
• 10/32 in tread depth for extended usable life
• Black sidewall, radial construction
• Speed rated Y (up to 186 mph)
• Extra Load (XL) rated for higher load capacity
• Summer-only compound: not for use when ambient temperatures are consistently below 45 degrees Fahrenheit

Specifications

What's Included

• 1x Mickey Thompson Street Comp GHT tire, size 255/45R18, 103Y XL

Frequently Asked Questions

The Street Comp GHT is Mickey Thompson's next-generation Ultra Ultra High Performance (UUHP) summer tire featuring an all-new advanced resin and silica-blended compound, redesigned aggressive asymmetric tread, and a lightweight reinforced internal structure built for high-horsepower applications.

Yes. Not suitable for use when ambient temperatures are consistently below 45 degrees Fahrenheit. Remove and store seasonally in cold-weather climates.

The 255/45R18 103Y XL is a popular size for muscle cars and performance vehicles running 18-inch wheels with a wide stance. Common fitments include the Ford Mustang GT rear on 18-inch wheel packages, Dodge Challenger rear axle on factory 18-inch setups, and similar rear-axle performance builds. Always verify rim width and offset before purchasing.

Because this tire uses an asymmetric tread design, rotation must be done side-to-side (swapping left and right on the same axle). Always ensure the outside shoulder faces outward as marked on the sidewall.

UTQG 300 AA A. Treadwear 300 is appropriate for a performance summer tire. Traction AA is the highest traction grade under the UTQG standard. Temperature A is the highest resistance to heat buildup at sustained high speeds.

Rated Y, indicating a speed capability exceeding 186 mph. Speed ratings reflect controlled laboratory test conditions and do not constitute a recommendation to exceed posted speed limits.

The advanced resin and silica-blended compound improves grip at lower and moderate temperatures and enhances water film dispersion. Combined with aggressive asymmetric tread channels, the GHT delivers Traction AA wet grip.

Yes. DOT-approved and designed primarily for public road use. Suitable for occasional autocross as well.

Store in a cool, dry, dark location away from ozone sources, UV exposure, and temperature extremes. Tires should be stored upright or stacked horizontally in protective bags.

Installation Instructions

1. Confirm size, load rating, and rim width are within the approved fitment range.
2. Have tires mounted and balanced by a qualified installer using a no-drop-center machine.
3. Ensure the asymmetric outside shoulder faces outward as marked.
4. Inflate to vehicle manufacturer specifications.
5. Torque lug nuts to spec in a star pattern.
6. Check for vibration at low speed before returning to normal driving.
7. Allow a 500 mile break-in period avoiding aggressive inputs.
8. Recheck tire pressure after the first 50 miles and monthly thereafter.

WARNING: This product can expose you to chemicals including lead and phthalates, which are known to the State of California to cause cancer and reproductive harm. For more information go to www.P65Warnings.ca.gov.