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Dunlop Grandtrek AT20 vs Cooper Discoverer AT3 LT — Compared

Relative Score (0–100): 60% professional tests, 40% owner reviews.

Discoverer AT3 LT is ahead, 74–46

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Category by category

Relative Score per category, 0–100. Open “Why this score” for the tests and owner ratings behind it.

  1. 43

    Dry

    Discoverer AT3 LT +34
    77
    Why this score
    SourceGrandtrek AT20Discoverer AT3 LT
    Reviews found online2983
  2. 42

    Wet

    Discoverer AT3 LT +37
    79
    Why this score
    SourceGrandtrek AT20Discoverer AT3 LT
    Reviews found online3382
  3. 49

    Snow

    Discoverer AT3 LT +22
    71
    Why this score
    SourceGrandtrek AT20Discoverer AT3 LT
    Reviews found online3673
  4. 51

    Comfort

    Discoverer AT3 LT +21
    72
    Why this score
    SourceGrandtrek AT20Discoverer AT3 LT
    Reviews found online3475
  5. 57

    Noise

    Discoverer AT3 LT +14
    71
    Why this score
    SourceGrandtrek AT20Discoverer AT3 LT
    Reviews found online4278
  6. 52

    Treadwear

    Discoverer AT3 LT +19
    71
    Why this score
    SourceGrandtrek AT20Discoverer AT3 LT
    Reviews found online4274
  7. 34

    Handling

    Discoverer AT3 LT +36
    70
    Why this score
    SourceGrandtrek AT20Discoverer AT3 LT
    Reviews found online3470
Scores at a glance
CategoryDunlop Grandtrek AT20Cooper Discoverer AT3 LT
Relative Score 46 74
Dry 43 77
Wet 42 79
Snow 49 71
Comfort 51 72
Noise 57 71
Treadwear 52 71
Handling 34 70

Higher is better. The Relative Score follows your weights below; category scores do not change.

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Recomputed
Headline score

Grandtrek AT20

Discoverer AT3 LT

Pros, cons & observations

Themes extracted from owner reviews found online — not the opinion of TireWheelGuide.

Tire A Grandtrek AT20

Pros

  • Exceptional tread life and high mileage capability (often exceeding 40,000 to 60,000+ miles)
  • Comfortable, smooth, and quiet ride on tarmac and highways
  • Good stability and predictable handling in dry, warm weather conditions

Cons

  • Extremely poor and potentially unsafe traction on wet roads, leading to sliding and long braking distances
  • Unreliable or hazardous performance in winter conditions like snow and ice
  • Subpar off-road capabilities, including low puncture resistance on gravel and poor traction in mud or sand
All owner themes in the Grandtrek AT20 review

Tire B Discoverer AT3 LT

Pros

  • Excellent towing stability with minimal sidewall flex under heavy loads
  • Surprisingly quiet and smooth on the highway for an all-terrain tire
  • Strong durability and wear resistance on rough gravel, rock, and dirt roads

Cons

  • Subpar performance in heavy snow, ice, or deep mud for some users
  • Occasional reports of balancing difficulties or initial cold-weather tire thumping
  • Isolated incidents of sidewall splitting or premature wear
All owner themes in the Discoverer AT3 LT review

Specs side by side

Attribute A · Dunlop Grandtrek AT20 B · Cooper Discoverer AT3 LT
CategoryAll SeasonPremium Touring All Season tire
Vehicle typeSUV and 4x4SUV and 4x4
Sizes available914
Rim diameters15″ – 18″16″ – 18″
Tread depth—16 - 17/32″
Treadwear warranty—60,000 mi
SidewallBlackwallBlack Side Wall - Raised Outline White Lettering
Max pressure—50 - 80 psi

Which one should you actually buy?

Dunlop Grandtrek AT20

Cooper Discoverer AT3 LT

Winner: Cooper Discoverer AT3 LT — better wet, handling and dry. It leads or ties in every category we score.

Pick tire B Your priority is wet-weather safety

Cooper Discoverer AT3 LT scores 79 vs 42 on wet.

Pick tire B You enjoy sharp, responsive handling

Cooper Discoverer AT3 LT scores 70 vs 34 on handling.

Pick tire B You want the most grip on dry roads

Cooper Discoverer AT3 LT scores 77 vs 43 on dry.

Pick tire B You drive through snowy winters

Cooper Discoverer AT3 LT scores 71 vs 49 on snow.

Tire A · Dunlop Grandtrek AT20
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Tire B · Cooper Discoverer AT3 LT
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How do we compare tires?

Every category score blends two independent signals. 60% comes from professional tire tests (braking distances, lap times, noise measurements), each result compared with every other tire in the same test and newer tests counting more. 40% comes from owner reviews found online, adjusted for how generously each site rates. Both use one scale: the average tested tire gets 70, the best 100. When a tire has only one of the two, the missing half is estimated from the other and the score stays closer to average; with no road test and fewer than five owner reviews it gets no score yet.

Community buzz from Reddit and forums is shown for context only — it never changes the score.

74

Leads

Discoverer AT3 LT

Amazon