AMP Terrain Attack M/T LT305/55R20

Looking for a 305/55R20 mud terrain tire? The AMP Terrain Attack M/T is available now at ThreePiece.us with free shipping on every order and Affirm financing at checkout.

The AMP Terrain Attack M/T is a mud-terrain tire built for drivers who spend real time off the pavement — in the mud, dirt, sand, gravel, and snow. Its aggressive tread pattern is designed to bite into loose and broken terrain, and reviewers repeatedly note strong grip on gravel and sand along with capable performance in snow. It carries an A traction rating, reflecting its focus on wet and low-grip surfaces where a purpose-built off-road tire earns its keep.

Despite its trail-first mission, the Terrain Attack M/T draws praise for surprisingly civil on-road manners, with owners describing it as smoother-riding than expected for a mud tire. That balance makes it a practical choice for a truck or SUV that has to commute during the week and still handle serious dirt on the weekend. It also has a reputation for solid value, giving off-road-minded shoppers an aggressive look and capability without stepping up to the priciest names.

Offered across a wide range of fitments, the model spans 17- to 28-inch rim diameters and comes in heavier-duty load ranges (D, E, and F) to suit half-ton, three-quarter-ton, and larger trucks. The breadth of load indexes and sizes means there is typically a configuration to match a lifted rig, a stock 4x4, or something in between.

AMP Terrain Attack M/T highlights

• Aggressive mud-terrain tread built for mud, dirt, sand, gravel, and snow
• A traction rating for confident grip on loose and low-traction surfaces
• Reviewers report strong grip on gravel and sand plus capable snow performance
• Surprisingly smooth, reliable road manners for a mud tire
• Available in D, E, and F load ranges to fit light-truck and heavy-duty rigs
• Wide fitment range spanning 17- to 28-inch rim diameters

What 305/55R20 means

In the size 305/55R20, 305 is the section width in millimeters (12.01 in), 55 is the aspect ratio — the sidewall stands 55% as tall as the tire is wide, or 167.8 mm (6.60 in) — R denotes radial construction, and 20 is the wheel diameter in inches. That works out to an overall diameter of about 33.21 inches, turning roughly 607 revolutions per mile. Overall diameter is what matters for speedometer accuracy and clearance when you change sizes, so compare it — not just the width — against your current tire.

The manufacturer lists the overall diameter of this specific tire as 33.46 inches — when clearance is tight, go by the published figure rather than the nominal size math.

The service description on this tire decodes to a load index of 121 — a maximum load of 3,197 lbs per tire, or 118 (2,910 lbs) per tire when mounted as duals. The speed symbol Q corresponds to a maximum sustained speed of 99 mph.

Load Range E corresponds to a 10-ply rating.

Specifications

Frequently asked questions

What kind of tire is the AMP Terrain Attack M/T?

The AMP Terrain Attack M/T in 305/55R20 is a mud terrain tire. Trucks, SUVs, and 4x4s — including lifted and heavy-duty rigs — that need serious off-road traction while still driving to and from the trail on the street.

Will 305/55R20 tires fit my vehicle?

Check the size molded into your current tire's sidewall or the tire placard inside the driver's door jamb — if it reads 305/55R20, this tire matches your vehicle's fitment. If you're changing sizes, compare overall diameter to keep your speedometer and clearances right. See every 305/55R20 tire in stock to compare options.

What does 121/118Q mean on the AMP Terrain Attack M/T?

121/118Q breaks down as load index 121 — rated for 3,197 lbs per tire (118, or 2,910 lbs, in dual fitment) — with a Q speed rating, good for a maximum sustained 99 mph.

Keep shopping

Shop all 305/55R20 tires, see every AMP Terrain Attack M/T size, explore mud terrain tires, or view all tires at ThreePiece.us.