Tire Review: Cooper Discoverer M+S

Updated Feb 25, 2014

Jims Ram Cooper MS JT 01-06-13 

COOPER DISCOVERER M+S 

Cooper’s Discoverer M+S helps snowbelt contractor deal with difficult winter driving conditions

By John Tiger

James Thompson, a local flooring contractor in New York’s Adirondack region whose rolling office is a 2011 Ram 1500 4Ă—4, is often faced with navigating steep, snowy driveways when servicing the needs of local homeowners. 

But he’s never been happy with the Goodyear Wranglers that came on his truck, saying winter performance is “less than satisfactory.”

To get out of slippery spots, Thompson utilized four-wheel drive.

He’d never thought about switching to more dedicated winter tires until Mike Stoltz, product manager at Cooper Tire (www.coopertire.com),  suggested running a set of Cooper’s premier top of the line snows, Discoverer M + S studdable models.

The switch from a good all-terrain to a dedicated snow tire (it has the mountain peak/snow flake symbol) was a real eye-opener for both Thompson and myself.

Cooper’s tread design and compounds were developed specifically for optimum traction in snow and on ice.Cooper’s tread design and compounds were developed specifically for optimum traction in snow and on ice.

Given that the Wranglers had a pretty aggressive tread pattern, we didn’t expect to notice a big difference in traction or overall driving performance. 

We were dead wrong: The Coopers were so good, that after a week of driving on them in the snow and ice that my bud remarked, “I’ll never go without snow tires again.” 

SLICK STUFF

We tested the Coopers on a warmish January day a week after Ma Nature dumped a little over a foot of snow on our local area.

The test bed was my driveway, a pretty steep grade a few tenths of a mile long, and coated with a few inches of hard ice and slick snow.

With the Coopers installed, Jim’s truck scampered up the drive like a clawed cat in both 2WD and 4WD, leaving us with an overall feel of sure-footedness and security.

While we could easily get the tires to spin in 2WD if with a heavy foot, in no way did we have to baby the Hemi to get the tires to bite.

Braking was surprisingly secure, as well, when we performed a hard stop test from 10 mph heading down the drive. The ABS barely engaged as the Coopers bit hard and stopped us within a few feet.

Back at the shop, we quickly removed the Coopers and put the stock Goodyears back under the Ram.

We were not prepared for the dramatic difference in performance. The truck did not feel nearly as stable, and our trips up and down the long driveway proved that our subjective opinion was well founded.

In 2WD, the Ram would barely make it up the drive as the slightest application of throttle caused the rear tires to spin.

In 4-Hi the Ram made it up easily, but not without lighting up the traction control light on the dash a few times. On the way down, our braking test revealed that the ABS system deployed almost immediately after we hit the brakes, showing the Wranglers were slipping substantially.

On open road, clear of snow and ice, the difference in tire noise at 55mph was barely perceptible, the Coopers being 2-3dB louder than the factory treads.

While that may not seem like a big difference, there was a decidedly louder and more defined note to the ear when running the Coopers.

As for bare pavement handling and ride, neither tire showed a discernible difference in performance as both provided a sure grip and a positive feel. 

SNOW TIRE DESIGNJim's snows tread 3 JT 01-06-13

Cooper’s Discoverer M+S dedicated snow/ice tire is very aggressive, with deep sipes and very pliable rubber tread blocks, especially on the outside edges.

These tread blocks can be easily manipulated with fingers, even in the colder weather; this pliability contributes to the tires’ grip on the ice.

Stud placement holes are strategically designed and located to give traction studs maximum support and bite.

Discoverer’s tread design features a zigzag deep sipe pattern to allow for snow and mud release, while at the same time providing a release for water when driving in rain or slushy conditions.

Cooper calls this “D Squared D2 Sipe Technology”, and despite the techy name, it works extremely well.

The outside tread blocks, known as “Snow-Groove,” are designed to provide a strong biting edge for snow and ice traction without reducing tread stiffness.

“Whether heading out to plow snow, getting around town, or driving to the ski slopes for a weekend, our Cooper Discoverer M+S is designed to dig through snow and maintain traction on ice,” notes Cooper’s Product Segment Manager, Jon Thomas.  

“This provides the confidence and control that is needed in the most severe of winter driving conditions.”

Cooper snow tire (left) and stock OEM street tire.

TIRE TEST CONCLUSION

Jim and I were both sold on the combination of price and performance of the Cooper Discoverer tires.

Together with a set of slick-looking aluminum wheels, mounting/balancing, and tire pressure monitor sensors, Jim spent just under $1,400 to have a complete set of snows and wheels at the ready when winter hits.

Now he’ll be able to navigate the slickest driveways and roads with his pickup, and he won’t have to worry about getting stuck on his way to a job site.

 

 

 

DOUBLE TREAD LIFE

Set up wheel/tire combos for both winter and summer driving

While we ordered a second set of wheels to go with the Cooper snows to enhance our test’s accuracy, the benefit to contractors in the Snowbelt like Jim Thompson isn’t hard to extract.

Having two sets of wheels/tires – one for winter use, the other for summer – maximizes driving performance and vehicle control. It also helps maximize mileage on both while keeping the nicer summer wheels looking good longer.

(Keeping the winter set clean by a weekly washing will keep them relatively corrosion-free.)

In Jim’s case, his winter rims (scored from The Wheel Wizard, www.stevescustom.com) are as nice or nicer than his stock Ram aluminums, so he will strive to keep them clean and corrosion-free.

For those headed down this route, here are some helpful tips for buying and owning two sets of wheels and tires:

  • Install a set of TPMS (Tire Pressure Monitor Sensors) when you buy the new rims. Jim found a very reasonable set for his Ram at MVP Wheels (www.mvpwheels.com) for $49; others go up to $149 for a set of four.
  • Before storing your winter or summer tires for the season, clean them thoroughly and apply a coat of wax or aluminum polish to protect them; keep air pressure in the tires to the recommended maximum, and store in a cool, dry place if possible.
  • If price is a concern, buy a set of steel wheels to mount the dedicated snow tires on. Steel wheels are half to a third the price of OE rims.