The Discoverer STT PRO is the most extreme all-season, off-road tire Cooper offers to date, providing remarkable off-road performance without sacrificing on-road traction.

  • Tread design helps to prevent stone retention
  • Armor Tek3 Construction for added tire durability
  • The shoulder of the tire was designed with soft surface "cleats" and mud "scoops"

Detailed Information

Type and Size
Tire Model
Cooper Discoverer STT PRO
Car Type
Light Truck / SUV
All Season
Rim Diameter
15 / 16 / 17 / 18 / 20 / 22 "
215 / 225 / 235 / 245 / 255 / 265 / 275 / 285 / 295 / 305 / 315 / 325 mm
Aspect Ratio
50 / 55 / 60 / 65 / 70 / 75 / 85 %
Special Features
Mud and Snow
Extra Load
Speed and Load
Speed Index
P (max 94 mph) ... Q (max 100 mph)
Load Index (max load for a tire)

Cooper Discoverer STT PRO Sizes & Specifications

Rim Model Size Index Features
R15 30x9.5 R15 LT 104Q 30x9.5 R15 LT 104Q
R15 31x10.5 R15 LT 109Q 31x10.5 R15 LT 109Q
R15 32x11.5 R15 LT 113Q 32x11.5 R15 LT 113Q
R15 33x12.5 R15 LT 108Q 33x12.5 R15 LT 108Q
R15 35x12.5 R15 LT 113Q 35x12.5 R15 LT 113Q
R16 215/85 R16 112Q 215/85 R16 112Q
R16 225/75 R16 112Q 225/75 R16 112Q
R16 235/85 R16 116Q 235/85 R16 116Q
R16 235/85 R16 120/116Q 235/85 R16 120/116Q
R16 245/75 R16 116Q 245/75 R16 116Q
R16 245/75 R16 120/116Q 245/75 R16 120/116Q
R16 265/75 R16 120Q 265/75 R16 120Q
R16 265/75 R16 123/120Q 265/75 R16 123/120Q
R16 285/75 R16 123Q 285/75 R16 123Q
R16 285/75 R16 126/123Q 285/75 R16 126/123Q
R16 305/70 R16 121Q 305/70 R16 121Q
R16 305/70 R16 124/121Q 305/70 R16 124/121Q
R16 315/75 R16 124Q 315/75 R16 124Q
R16 315/75 R16 127/124Q 315/75 R16 127/124Q
R17 37x12.5 R17 LT 124Q 37x12.5 R17 LT 124Q
R17 37x13.5 R17 LT 121Q 37x13.5 R17 LT 121Q
R17 40x13.5 R17 LT 121Q 40x13.5 R17 LT 121Q
R17 255/75 R17 108Q 255/75 R17 108Q
R17 265/70 R17 118Q 265/70 R17 118Q
R17 265/70 R17 121/118Q 265/70 R17 121/118Q
R17 285/70 R17 118Q 285/70 R17 118Q
R17 285/70 R17 121/118Q 285/70 R17 121/118Q
R17 295/70 R17 118Q 295/70 R17 118Q
R17 295/70 R17 121/118Q 295/70 R17 121/118Q
R17 305/65 R17 118Q 305/65 R17 118Q
R17 305/65 R17 121/118Q 305/65 R17 121/118Q
R17 315/70 R17 118Q 315/70 R17 118Q
R17 315/70 R17 121/118Q 315/70 R17 121/118Q
R18 37x13.5 R18 LT 124Q 37x13.5 R18 LT 124Q
R18 38x15.5 R18 LT 128Q 38x15.5 R18 LT 128Q
R18 275/65 R18 120Q 275/65 R18 120Q
R18 275/65 R18 123/120Q 275/65 R18 123/120Q
R18 275/70 R18 122P 275/70 R18 122P
R18 275/70 R18 125/122P 275/70 R18 125/122P
R18 285/65 R18 122Q 285/65 R18 122Q
R18 285/65 R18 125/122Q 285/65 R18 125/122Q
R18 295/70 R18 126P 295/70 R18 126P
R18 295/70 R18 129P 295/70 R18 129P
R18 305/60 R18 118Q 305/60 R18 118Q
R18 305/60 R18 121/118Q 305/60 R18 121/118Q
R18 305/70 R18 123Q 305/70 R18 123Q
R18 305/70 R18 126/123Q 305/70 R18 126/123Q
R18 325/65 R18 124Q 325/65 R18 124Q
R18 325/65 R18 127/124Q 325/65 R18 127/124Q
R20 35x12.5 R20 LT 121 35x12.5 R20 LT 121
R20 35x12.5 R20 LT 121Q 35x12.5 R20 LT 121Q
R20 35x13.5 R20 LT 122Q 35x13.5 R20 LT 122Q
R20 37x12.5 R20 LT 126Q 37x12.5 R20 LT 126Q
R20 37x13.5 R20 LT 127Q 37x13.5 R20 LT 127Q
R20 38x13.5 R20 LT 123Q 38x13.5 R20 LT 123Q
R20 38x15.5 R20 LT 128Q 38x15.5 R20 LT 128Q
R20 275/65 R20 123Q 275/65 R20 123Q
R20 275/65 R20 126/123Q 275/65 R20 126/123Q
R20 295/55 R20 120P 295/55 R20 120P
R20 295/55 R20 123/120Q 295/55 R20 123/120Q
R20 295/60 R20 123Q 295/60 R20 123Q
R20 295/60 R20 126/123Q 295/60 R20 126/123Q
R20 295/65 R20 126Q 295/65 R20 126Q
R20 295/65 R20 129/126Q 295/65 R20 129/126Q
R20 305/55 R20 118Q 305/55 R20 118Q
R20 305/55 R20 121/118Q 305/55 R20 121/118Q
R22 35x12.5 R22 LT 117Q 35x12.5 R22 LT 117Q
R22 37x13.5 R22 LT 123Q 37x13.5 R22 LT 123Q
R22 325/50 R22 122Q 325/50 R22 122Q

Amazon Reviews Cooper Discoverer STT PRO

Questions and Answers

  • Dec 06, 2017

    S4X4: Discoverer STT Pro. Review.

    Looking for a bit of feedback on your next set of tires? Here's our take on the Cooper Discoverer STT Pro after putting them through the motions both on and off road in Vermont.

  • Jul 07, 2017

    Cooper Discoverer STT Pro Tire Review

    The Discoverer STT PRO provides superior reliability and durability with Armor-Tek3 construction that adds strength to the sidewall and tread area, and mud release dimples and scoops that prevent build-up and improve traction in off-road conditions. The Discoverer STT PRO also features a silica-infused tread compound to improve traction in wet conditions and lowers rolling resistance for improved fuel mileage.

  • Sep 11, 2016

    Cooper discoverer stt pro

  • Sep 01, 2016

    Cooper Discoverer STT Pro Review - 315/70R17

    So after 500 miles on the road and a 6 hour adventure on the trail, we have finally broken in these Cooper Discoverer STT Pro tires. In this video I will break down some specifics and give you my overall impressions.... it's review time!

  • Jun 01, 2015

    Cooper Discoverer STT Pro - Off Road Mud Tire Review - In 4K

    Cooper's new STT Pro mud tire is a good balance between off-road and mud performance and a highway ride that is possible to live with.