Cooper Discoverer Road Trail AT vs Nitto Terra Grappler G3
In the 2 independent tests that ran both tyres, the Cooper Discoverer Road Trail AT finished ahead 2 times and the Terra Grappler G3 not once. The Discoverer Road Trail AT was stronger in snow, ice and comfort, the Terra Grappler G3 in wet.
Performance profile
14 measurements from the 2 shared tests, each tyre shown as its share of the better figure in every test.
Where each is furthest ahead
Discoverer Road Trail AT
Terra Grappler G3
Point at or tap any spoke for both tyres' figures.
In each test the better of the two figures counts as 100% and the other as its share of it, so a 36 m stop against 34.2 m is 95%; each spoke averages the shared tests that recorded it.
Where each scores higher
Discoverer Road Trail AT
Terra Grappler G3
Point at or tap any spoke for both tyres' figures.
Category scores are percentiles among tyres of the same season and class: 90 means this tyre out-performs 90% of them, measured across every test we hold, not only the ones it appeared in.
Every measurement, side by side
Averages of the figures both tyres posted in the same tests. The gap is the average of each test's own gap, so figures from different cars and years are never mixed. Wins count the tests in which each tyre did better.
| Measurement | Discoverer Road Trail AT | Gap | Terra Grappler G3 | Wins |
|---|---|---|---|---|
| Dry Level | ||||
| Dry Braking m | 40.84 | 6% | 38.4 | 0-1 |
| Dry Circle g | 0.74 | = | 0.74 | 0-0 |
| Subj. Road Score pts | scored | 7.7% | scored | 1-0 |
| Wet Terra Grappler G3 ahead | ||||
| Wet Braking m | 52.43 | 8.1% | 48.16 | 0-1 |
| Wet Handling s | 37.28 | 2.5% | 36.35 | 0-1 |
| Wet Circle g | 0.59 | 3.4% | 0.61 | 0-1 |
| Snow Discoverer Road Trail AT ahead | ||||
| Snow Braking m | 21.81 | 17.6% | 26.48 | 1-0 |
| Snow Traction m | 12.95 | 6% | 13.77 | 1-0 |
| Snow Handling s | 27.69 | 7.5% | 29.93 | 1-0 |
| Subj. Snow Handling pts | scored | 31.6% | scored | 1-0 |
| Ice Discoverer Road Trail AT ahead | ||||
| Ice Braking m | 13.52 | 7.3% | 14.58 | 1-0 |
| Ice Traction s | 5.79 | 4.5% | 6.06 | 1-0 |
| Comfort Discoverer Road Trail AT ahead | ||||
| Subj. Comfort pts | scored | 11.5% | scored | 1-0 |
| Subj. Noise pts | scored | 16.7% | scored | 1-0 |
Braking distances and lap times are better when lower; speeds, wear and grip figures when higher. A test's figures are its own: sizes, cars, surfaces and temperatures differ from one to the next, which is why the averages here are only ever of tests the two tyres shared.
Head to head in 2 tests, 2024 to 2026
Each row is one published test in which both tyres ran on the same car, in the same size, on the same day. The line is the whole field, winner on the left.
| Test | Discoverer Road Trail AT | Field | Terra Grappler G3 |
|---|---|---|---|
| 2026 Tire Rack All Terrain Tyre Snow Test | P9 of 30 | P27 of 30 | |
| 2024 Tire Rack All Terrain Tyres On-Road Test | P1 of 12 | P3 of 12 |
Discoverer Road Trail AT vs Terra Grappler G3: your questions
Is the Cooper Discoverer Road Trail AT or the Nitto Terra Grappler G3 the better tyre?
In the 2 independent tests that ran both tyres, the Cooper Discoverer Road Trail AT finished ahead 2 times and the Terra Grappler G3 not once. On the Tyre Reviews Score, which weighs every test and review we hold, the Discoverer Road Trail AT scores 8.5 and the Terra Grappler G3 8.5 out of 10.
Which is better in the wet, the Discoverer Road Trail AT or the Terra Grappler G3?
The Terra Grappler G3 led 3 of the 3 wet measurements the shared tests recorded.
Which is better in the dry?
Across the shared tests the dry measurements are split 1-1 between the Discoverer Road Trail AT and the Terra Grappler G3.
Which is better in snow?
The Discoverer Road Trail AT led 4 of the 4 snow measurements the shared tests recorded.
What do owners say?
Owners rate the Discoverer Road Trail AT 87% from 7 reviews; the Terra Grappler G3 has no owner reviews yet.
More comparisons with these tyres
Run either of these?
Your review is the part of this page no test can supply: how the tyre wore, how it aged, what it was like in the rain in year three. It takes about five minutes.
Review the Discoverer Road Trail AT Review the Terra Grappler G3
Where this data comes from
Finishing positions and measurements are transcribed from each published test. A test only counts here when both tyres ran in it, so every figure was recorded on the same car, size and day as the one it is compared to.
About the TR Score
The Tyre Reviews Score rates each tyre out of 10 from every independent test result and vetted owner review we hold, so two tyres can be compared even before a test has run them together.
Who does the testing
Every test published as a Tyre Reviews test is run by Jonathan Benson, who has been testing tyres independently since 2007.