Relative Score (0–100): the weighted average of the categories below, each 60% road tests and 40% owner reviews (comfort 40/60). Based on 0 + 1 road tests and 973 + 33 owner reviews. How we score
Terra Grappler G3 is ahead, 77–69
Both Amazon links then search this exact size.
TireWheelGuide may earn a commission from purchases made through these links.
Tests – · none yet Owners 67 · 973 reviews
“I have a set of 275/60R20 on my dodge work truck. Coming up on 35k. Oilfield roads. These tires are ride smooth and are quiet. They have done well in the snow and mud for me. I will purchase a set of these for my own personal truck once needed. These are great tires.”
Tests 74 · 1 test Owners 83 · 33 reviews
Best test result: #1 of 12 in 2024 Tire Rack All Terrain Tyres On-Road Test (wet braking)
Relative Score per category, 0–100. Open “Why this score” for the tests and owner ratings behind it.
| Source | Discoverer A/T3 | Terra Grappler G3 |
|---|---|---|
| Professional tests (TWG score) · – / 1 tests | ≈ 71 (est.) | 86 |
| Reviews found online | 75 | 81 |
Discoverer A/T3: 60% × 70.7 (est.) + 40% × 74.6 = 72
Terra Grappler G3: 60% × 86.1 + 40% × 81.4 = 84
No road tests of dry for Discoverer A/T3. The test half is estimated from the owner ratings, as far as owners and testers agree (correlation 0.41).
| Source | Discoverer A/T3 | Terra Grappler G3 |
|---|---|---|
| Professional tests (TWG score) · – / 1 tests | ≈ 74 (est.) | 87 |
| Reviews found online | 76 | 84 |
Discoverer A/T3: 60% × 73.7 (est.) + 40% × 76.2 = 75
Terra Grappler G3: 60% × 87 + 40% × 83.9 = 86
No road tests of wet for Discoverer A/T3. The test half is estimated from the owner ratings, as far as owners and testers agree (correlation 0.55).
| Source | Discoverer A/T3 | Terra Grappler G3 |
|---|---|---|
| Professional tests (TWG score) · – / 1 tests | ≈ 70 (est.) | 33 |
| Reviews found online | 67 | 80 |
Discoverer A/T3: 60% × 69.5 (est.) + 40% × 67.4 = 69
Terra Grappler G3: 60% × 33.2 + 40% × 80.4 = 52
No road tests of snow for Discoverer A/T3. The test half is estimated from the owner ratings, as far as owners and testers agree (correlation 0.32).
| Source | Discoverer A/T3 | Terra Grappler G3 |
|---|---|---|
| Professional tests (TWG score) · – / 1 tests | ≈ 68 (est.) | 71 |
| Reviews found online | 67 | 80 |
Discoverer A/T3: 40% × 68.2 (est.) + 60% × 66.5 = 67
Terra Grappler G3: 40% × 70.7 + 60% × 79.5 = 76
No road tests of comfort for Discoverer A/T3. The test half is estimated from the owner ratings, as far as owners and testers agree (correlation 0.20).
| Source | Discoverer A/T3 | Terra Grappler G3 |
|---|---|---|
| Professional tests (TWG score) · – / 1 tests | ≈ 66 (est.) | 66 |
| Reviews found online | 65 | 78 |
Discoverer A/T3: 60% × 66.4 (est.) + 40% × 65.2 = 66
Terra Grappler G3: 60% × 66.1 + 40% × 78 = 71
No road tests of noise for Discoverer A/T3. The test half is the tested tires’ average (66): owners’ noise ratings barely follow the road tests.
| Source | Discoverer A/T3 | Terra Grappler G3 |
|---|---|---|
| Professional tests (TWG score) | ≈ 61 (est.) | ≈ 74 (est.) |
| Reviews found online | 52 | 87 |
Discoverer A/T3: 60% × 61.2 (est.) + 40% × 51.7 = 57
Terra Grappler G3: 60% × 73.9 (est.) + 40% × 87 = 79
No road tests of treadwear for Discoverer A/T3. The test half is estimated from the owner ratings, as far as owners and testers agree (correlation 0.36).
No road tests of treadwear for Terra Grappler G3. The test half is estimated from the owner ratings, as far as owners and testers agree (correlation 0.36).
| Source | Discoverer A/T3 | Terra Grappler G3 |
|---|---|---|
| Reviews found online | 65 | – |
| Category | Cooper Discoverer A/T3 | Nitto Terra Grappler G3 |
|---|---|---|
| Relative Score | 69 | 77 |
| Dry | 72 | 84 |
| Wet | 75 | 86 |
| Snow | 69 | 52 |
| Comfort | 67 | 76 |
| Noise | 66 | 71 |
| Treadwear | 57 | 79 |
| Handling (owners) | 65 | – |
Higher is better. The Relative Score follows your weights below; category scores do not change.
Wet grip starts at “Important”. Treadwear starts at “Neutral” here: road tests measured it for at most one of the two tires, so it rests on owner reviews. Move the sliders and the scores update instantly.
Only one of the two tires has a score here, so this weight changes nothing in the head-to-head.
Discoverer A/T3
Terra Grappler G3
Only categories both tires have data for count toward the headline score.
Per discipline: the average % of the best tire over every test both tires were in, and how many of those tests each one won. “Different tests” rows compare results from separate tests.
| Discipline | Category | Discoverer A/T3 | Terra Grappler G3 | Δ | Head-to-head |
|---|---|---|---|---|---|
| Also published by the testers (not in the score) | |||||
| Overall Ranking | Overall | #13/13 2018 SA4x4 All-Terrain Tire Test R17 | #27/30 2026 Tire Rack All Terrain Tyre Snow Test | – | Different tests |
Themes extracted from owner reviews found online — not the opinion of TireWheelGuide.
From Reddit, forums and review threads. Not part of our score
The community expresses overwhelmingly positive feedback for the Cooper Discoverer A/T3, praising its strong performance on the highway, good wet and snow traction, and smooth, relatively quiet ride quality. Many users note that the tires wear well over tens of thousands of miles, though some mention that they can get slightly louder as they age and tend to pack up in deep mud. Overall, users consider them to be reliable, high-value all-terrain tires suitable for daily driving, towing, and light off-roading.
“Put a set on a day after I purchased my truck. Have about 8500 miles on them and no complaints whatsoever. Been on a 3000 trip with them not towing and a 2400 mile trip towing a 8K travel trailer. No problems on either trip. I'll get another set when these wear out, hopefully many miles down the road. No sign of wear yet!”
“I have put 18k miles on the discoverer AT/3's on my F150 since last November and have been impressed with them so far. The tread seems to be wearing well, and I haven't noticed any more road noise than the BF Goodrich rugged trail T/As that I had on it before, and the ride quality has also been good compared to other tires. I haven't used them off road much but they did well in snow last winter, and have got good traction on wet pavement. Overall, I'd definitely say their good tires for the money, with their performance and the fact that they come with a 55,000 mile warranty.”
“Just a minor point... The tire in the picture is actually the Cooper Discoverer AT3 LT, not a Discoverer A/T3. They're different models, and Cooper does a really poor job IMO differentiating between them. I had Cooper Discoverer A/T3's E range on my 2nd Gen Tundra and LOVED them. That truck is gone, and now my Taco has Disco A/T3's and I'm finding them every bit as transformative.”
Based on 25 community posts
We haven't collected enough community discussion about this tire yet.
| Attribute | A · Cooper Discoverer A/T3 | B · Nitto Terra Grappler G3 |
|---|---|---|
| Category | All-Terrain tire | All-Terrain tire |
| Vehicle type | SUV and 4x4 | SUV and 4x4 |
| Sizes available | 14 | 76 |
| Rim diameters | 15″ – 22″ | 16″ – 22″ |
| Tread depth | 14 - 17/32″ | 12.7/32″ |
| UTQG | 560 A B | 600 A B |
| Treadwear warranty | — | 70,000 mi |
| Sidewall | Black Side Wall - Raised Outline White Lettering | Blackwall |
| Max pressure | 44 - 80 psi | 50 psi |
| Sizes in common | 10 | 10 |
Cooper Discoverer A/T3
Nitto Terra Grappler G3
Winner: Nitto Terra Grappler G3 — better treadwear, dry and wet. Pick the Cooper Discoverer A/T3 if snow matters most to you.
Nitto Terra Grappler G3 scores 79 vs 57 on treadwear.
Cooper Discoverer A/T3 scores 69 vs 52 on snow.
Nitto Terra Grappler G3 scores 84 vs 72 on dry.
Nitto Terra Grappler G3 scores 86 vs 75 on wet.
TireWheelGuide may earn a commission from purchases made through these links.
Nitto Terra Grappler G3, 86 vs 75 on our wet score.
Nitto Terra Grappler G3, 84 vs 72 on our dry score.
Cooper Discoverer A/T3, 69 vs 52 on our snow score.
Nitto Terra Grappler G3, 71 vs 66 on our noise score.
Nitto Terra Grappler G3, 76 vs 67 on our comfort score.
Nitto Terra Grappler G3, 79 vs 57 on our treadwear score.
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.
Handling is the exception: road tests measure it inside the dry and wet scores, so its own row comes from owner ratings only and starts as less important.
Community buzz from Reddit and forums is shown for context only — it never changes the score. Full methodology
