Drew Hardin

Cold Remedies

outdoorlife-editor — Tue, 18 Sep 2007 12:26:37 -0400

The coming of winter means it's time to prepare your truck for the cold weather ahead. For those of you in the South, "cold" is a relative term, especially when compared with the subzero temperatures and head-high snowdrifts your brethren in the North have to cope with. But no matter where you live, some early preventive maintenance will see your rig safely through to spring.

Start the season with fresh windshield wiper blades. Summer heat can dry and crack the blades' rubber, rendering them ineffective when you need them most. If you live in a snowy climate, you might consider investing in winter wipers, which have rubber boots to keep snow and ice from packing into the arm mechanism. Change back to the original wipers in the spring, though. The heavier winter wipers can strain your truck's wiper motor.

Be sure to have plenty of windshield washer fluid on hand. You'll use more in the winter months to clear windshield-smearing muck. Be sure the washer fluid is rated to handle the coldest weather you expect-some of the mass-market brands freeze at minus 10 degrees Fahrenheit. Specialty deicers and washer concentrates claim to stay effective to from minus 30 to minus 45 degrees, depending on the brand.
How long has it been since you flushed your truck's cooling system and replaced the fluids? You should do this every two years, so if you didn't do it last year, now is the time. The recommended 50-50 ratio of antifreeze to water should keep things flowing to about minus 30 degrees, though some manufacturers rate their products to minus 80.

Make sure the battery is in good condition. These days, batteries generally last only four years or so (we've seen some go south in as few as two), and you'll get little warning before it gives up. Compounding this situation is the fact that cold weather reduces cranking power-by up to 50 percent when the temperature drops below zero. If it's time for a new battery, look for one with as many cold-cranking amps (CCA) as you can find. Ratings of more than 600 CCA are best.

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Under the Hood

Your engine-bay checkup should also include an inspection of belts and hoses, since cold weather makes rubber brittle. And how
is the general condition of your engine's tune? The last thing
you want is a stumbling, balky engine that could strand you as a storm front moves in. Changing the oil to a lower viscosity will provide better flow in freezing temperatures, but don't go below your truck maker's viscosity recommendations.

If the winters where you live
get especially frigid, you might want to invest in an under-hood heater to make it easier to start your truck in the mornings. These run the gamut from battery-tray and oil-pan blankets to engine-block heaters.
Inspect the chassis. Grease any lubrication fittings and check to make sure the rubber boots over driveline joints are intact. A torn boot allows moisture and road spray to seep in, which leads to damaged joints. Have a muffler shop inspect the exhaust system for leaks that could be allowing carbon monoxide into the cab.

New Shoes

When the truck's on the rack, swap on a set of winter tires, or at the very least replace worn tires with a fresh set. You'll need the new tread's biting edges to gain traction in slush and snow. When tire shopping, look for the mountain-and-snowflake icon, which indicates that tires have passed rigorous winter-weather performance tests.

Check the air pressure in the tires often. A temperature drop of 10 degrees reduces tire pressure by 1 pound per square inch, which can add up as late fall becomes midwinter. Remember, too, that if air was added to tires in a heated garage, the pressure will drop when you drive outside.

If your local roads require snow chains, make sure the chains fit your truck's tires properly and that you practice mounting them before really miserable conditions set in.. Chains should be attached to the truck's drive wheels; if you use four-wheel drive in the snow you should have two sets and mount them to the front and rear wheels.

Finally, keep your fuel tank more than half full, to prevent moisture from developing in the tank and creating icing problems. (Fuel-tank and fuel-line deicers are available, too, to prevent freezing between the tank and the engine.) A half-full tank will also ensure that you have plenty of fuel on hand should you become stranded and need to run the engine occasionally so you can use the heater. Just be sure that your tailpipes are free of ice and snow before you do.

Winter Safety Kit

Keep this gear in your truck during winter in case of emergency.

Wool blanket

Dry clothing, socks, boots, gloves

Snacks and water

First-aid kit

Flashlight with fresh batteries

Flares

Hand and/or body warmers

Windshield scraper/broom

Extra windshield-washer fluid

Jumper cables or portable jump-starter

Kitty litter or sand for traction

Shovel

Well-charged cell phone or CB radio

Getting Hitched

outdoorlife-editor — Tue, 18 Sep 2007 12:26:36 -0400

Pickup trucks are made to haul gear, not necessarily tow it. Whether the plan is to take a bass boat to the lake or a trailer cross-country, towing requires specialized components to get the job done right and safely. These days you can choose from a number of comprehensive towing packages and drive a veritable tugboat right off the showroom floor. But if a towing package isn't part of a truck's original equipment, upgrades might be necessary before you hitch up and head out.

Weighty Matters

Weight is the critical element in determining a truck's ability to tow safely. This doesn't just mean the weight of the trailer and its contents, but also the weight of the gear packed in the truck, the passengers and the truck itself. Every truck has a Gross Com-bined Weight Rating (GCWR), which is the maximum gross combined weight it can handle without the risk of damage. If your intended GCW is beyond your truck's rating, you have two choices: Either upgrade the entire vehicle or lighten the load to within your truck's GCWR.

Driving Tips

Hitching Up If you're going to be hitching alone most of the time, invest in one of the aftermarket devices that helps guide the tongue onto the ball (such
as the Hitch 'n Go, a V-shaped ramp that attaches to the hitch), or one that allows the hitch ball to move to the trailer when the two are close.

Lock the Overdrive

If you find your automatic transmission constantly upshifting and downshifting (typical in a hilly environment), lock out overdrive to avoid undue transmission strain. When you're back in the flatlands, re-engage overdrive to help fuel economy.

Don't Brake

If the trailer starts to sway at speed, do not hit your truck's brakes. Lower your speed gradually and hold the steering wheel as straight as possible. Try to slow the trailer by using the trailer brakes (if so equipped).

Check the Hitch

After you've been trailering for 50 miles or so, pull off the road and check to make sure the hitch coupling is secure, your safety chains are still connected and your electrical connection is still attached.

In addition to having enough weight-carrying capacity and the right trailer hitch, a well-equipped tow rig should be outfitted with the following accessories. 1. Trailer
mirrors/mirror extensions: These give the driver adequate visibility aft of his land train. 2. Trailer wiring harness: Allows you to hook up the electric brakes and the brake and tail lights on the trailer. 3. Trailer brakes: Required in certain states for trailers weighing more than 1,500 pounds. Can be electrically or hydraulically operated. 4. Safety chains: Keep the trailer attached to the tow rig should the tongue uncouple from the hitch.
5. Auxiliary transmission cooler: Used on automatic transmissions to help maintain the fluid's proper operating temperature.

Gas Pains

outdoorlife-editor — Tue, 18 Sep 2007 12:26:36 -0400

With regular-grade gasoline at well over $2 per gallon, a trip to the gas pump can be an expensive proposition, especially if you drive a full-size truck. You can slow the drain from your wallet, however, by following these tips.

Stay Tuned: Engine efficiency is the key to improving fuel economy. According to the California Energy Commission's Consumer Energy Center (CEC), overlooked maintenance items (engines that are out of tune, clogged fuel injectors, dirty air filters, etc.) and underinflated tires can increase your fuel costs up to 13 percent.

Check the Oil: When your truck is in for its next tune-up, ask if you're using the right weight of oil. Oil that's thicker than necessary makes the engine work harder to circulate it. According to a bulletin from Chevron, if you reduce engine friction 50 percent by improving the motor oil you use, you can increase fuel economy nearly 6 percent.

Improve Performance: Most aftermarket engine equipment was designed to improve vehicle performance, but many of these components also improve fuel economy. A freer-flowing air filter and exhaust system, combined with a more powerful ignition, can not only pep up your truck's performance but add a few miles per gallon as well.

One caveat: Many who have installed these kinds of parts report
a drop in fuel economy. Often that's due to a heavier right foot eager to "test" the expected performance improvements.

Slow Down: Driving more efficiently can save you up to 20 percent in fuel costs, says the CEC. Accelerate gently, don't let your truck idle for more than a few minutes, and watch your speed.

If you slow down from 75 to 65 mph, for example, you can reduce fuel costs by 13 percent.
Chevron has also found that air conditioner use can reduce fuel economy by more than 20 percent, so use the truck's flow-through ventilation system to stay cool whenever you can.

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Get Aerodynamic: Automak-ers know that the least expensive way to gain fuel economy is to improve how a vehicle moves through the air. That's tough to accomplish with a squared-off vehicle like a truck, despite the many advances in engineering. However, you can improve your truck's aerodynamics by keeping the windows up whenever possible and properly inflating your tires to reduce rolling resistance.

Adding a tonneau cover or cab-high shell to the bed will also reduce air turbulence (drag) in the cargo box, which can improve mileage. Avoid using external cargo racks, which disrupt air flow over the roof.
Climate can affect fuel economy anywhere from 5 to 13 percent, according to Chevron. Not much you can do about that.

Buy What You Need: One way you can save money at the pump is by not "over-buying" the grade of gasoline you need.

Unless your engine is experiencing detonation or other specific problems, there's no performance or mileage benefit to using gasoline with a higher octane rating than your vehicle manufacturer recommends. So why spend the extra 10 or 20 cents per gallon?

Unfortunately, none of these tips will double your fuel economy. But taken together over time they can add up to fewer stops at the gas pump.

What Will That Trip Cost?

The Fuel Cost Calculator (fuelcostcalculator.com), hosted by AAA, estimates how much fuel will be required and what it will cost for a trip based on the vehicle you drive, using up-to-date regional gasoline prices. Here's what a hypothetical 726-mile round trip from Los Angeles to San Francisco cost at press time using these vehicles. Note: Gas prices might be higher now.

Caring for a Classic

outdoorlife-editor — Tue, 18 Sep 2007 12:26:34 -0400

Trucks live longer these days. Tighter manufacturing tolerances, greater rust resistance from paint and undercoatings, more efficient lubricants and cleaner-burning fuels help a well-cared-for pickup easily rack up more than 100,000 miles-sometimes even double that-before requiring a major engine overhaul.

Yet the way we drive our trucks works against their aging gracefully. A sportsman typically either uses his truck to the point of abuse or relegates it to hunting-lodge duty, where it sits for weeks or months at a time. Both extremes create their own problems.

If an owner is diligent about regular maintenance and monitors vulnerable components for wear, however, there's no reason why even the hardest-
working pickup can't deliver a couple of full-odometer rotations. Here's a guide to those areas most prone to breakage-the weakest links, as it were. The secret to keeping a truck in service is to replace or repair these weak links well before they break.

The Dry Rubber Band

It doesn't take much stretching to snap an old rubber band. That's because rubber dries out over time, and age
attacks a vehicle's rubber components whether it's being driven or not. In fact, letting a truck sit can be much worse than piling mileage on it, since the rubber pieces in and around the driveline won't get any lubrication.

1. Under the Hood

Under-hood heat speeds the aging process, so watch out for weak links in the engine compartment. Check fuel lines, radiator and vacuum hoses, spark-plug wire insulation and anything else made from rubber for cracks, discoloration or other signs of aging. Hoses under pressure-like those to and from the radiator-bulge when they deteriorate. If you don't see obvious bulging, push the hose with your finger to test for soft spots.

2. Check the Belts

Though it's made from several materials in addition to rubber, the accessory drive belt will also crack and fray with age. Be sure to look it over carefully.

3. Brake Lines

Inspect the brake fluid lines between the chassis hard lines and the brakes. These bulge as they age and can be replaced with stainless-steel-braided hose.

Rubber boots that protect the constant-velocity (CV) joints or U-joints in the drive axles are susceptible to drying and damage from sharp trail hazards. If you find even the smallest tear in a CV boot, replace it immediately; otherwise the joints will freeze.

4. Lube the Joints

Driveline joints and yokes that are not protected by boots should be lubed at least as often as the manufacturer's severe-duty maintenance schedule recommends. Even the rubber breather tubes in the differentials will deteriorate over time; some four-wheelers replace these with either steel-braided hose or a sturdier neoprene rubber.

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5. Tire Troubles

Age can also dry out tires. Cracked sidewalls are a hint that a tire isn't as structurally sound as it used to be.

6. Replace Gaskets

Many undercarriage components, including the oil pan, transmission, transfer case and differentials, are sealed with cork or rubber gaskets. These dry out and deteriorate as they age, particularly in a vehicle that doesn't get much use.

7. Look for leaks

If fluid can seep out around seals, contaminants can get in. This is particularly important for vehicles that spend a lot of time in water, because water ruins the lubricating properties of grease.

8. Repack hubs

If your truck has manual locking hubs, repack them with grease at the same intervals recommended for wheel bearings. A truck's mechanical transfer-case linkage should be lubricated at the first sign of stiffness. It's also a good idea to engage the transfer case and front
drive axles at least once a month, so moving parts don't freeze from disuse.

Smoke and Smells

9. Watch your Oil

A little puff of smoke at start-up or having to add a quart or so of oil between changes is normal for an older engine. However, if you're adding three or more quarts of oil between changes, or that puff of smoke becomes a James Bond-like smoke screen, it's time to rebuild the engine. A drop in power (even if the engine still runs smoothly) or a sustained clatter at start-up should also send you to your mechanic.

10. Replace the clutch

If the clutch on your truck slips or feels like the gear isn't engaged even when the pedal is all the way out, clutch work is in order. In an automatic, a burnt smell to the transmission fluid can mean trouble, as does a transmission that won't stay in gear or one that makes prolonged, mushy changes between gears.

Chasing down these weak links is like painting the Golden Gate Bridge-as soon as one end is finished, the job starts all over again. However, taking time now and again to check the potential trouble spots is always preferable to having to make the long walk home when a weak link breaks.

Bed Protection

outdoorlife-editor — Tue, 18 Sep 2007 12:26:34 -0400

Most sportsmen I know value their pickup trucks more for utility than for beauty. Yet this doesn't mean that your truck's bed has to become a dented mess from loading and unloading your outdoor gear. These days, truck owners have more bed-protection options than ever.

The Drop-In Option

Drop-ins are the most common type of bed liner; some truck manufacturers even offer them as an option. Made from polyethylene or other plastic materials, these liners are manufactured to fit specific truck bed applications and literally drop into place during
installation. Fasteners attach the liner to the sheet metal. A separate tailgate protector that screws into place is sold with the liner.

Current drop-in-liner technology includes non-skid surfaces, fade-resistant pigments and bed-floor ribs that both cushion cargo and promote air ventilation between the liner and the sheet metal to reduce the risk of rust caused by trapped moisture. The installation of a typical drop-in liner takes less than an hour using simple hand tools.

Over-the-bed-rail drop-ins offer the most protection for those who typically load gear from the sides of their truck. Under-rail models are a good choice if you're also adding a tonneau cover or bed cap. Expect to pay $250 to $300 for a drop-in liner.

Spray-on Protection

As the name implies, spray-on liners consist of a rubberized material (such as the polyurethane-polyurea elastomer used by Line-X) that's sprayed into the bed to form a 1/8- to Â¼-inch-thick coating.

Professional installation takes several hours, and though the material dries to the touch in minutes, the liner should cure for at least 24 hours before heavy use.

Since every spray-on liner is a custom application, you can choose which areas of the truck you want protected, including the lower fenders, rocker panels or floorboards for hose-out cleaning. And since spray-ons eliminate the need for attaching hardware, your bed is totally protected. Prices for a spray-on liner vary greatly with the options you choose, but plan to pay $400 to $600 for the job.

Which Works Best?

Generally, drop-ins are thicker and therefore provide better protection from really heavy cargo. They're also less expensive, easier to install and removable. A spray-on liner, on the other hand, forms a permanent bond with the sheet metal, sealing out corrosion-causing moisture that can be trapped between a drop-in and the bed floor. Spray-ons also give your truck bed a custom look, especially if the liner is color-matched to your truck's paint job.

Where to Buy them

Good sources for bed liners include Durakon (Duraliner drop-in bed liners, Durasport bed mats; 800-695-4637; www.durakon.com); Herculiner (877-437-2854; www.herculiner.com); Line-X (spray-on bed liners; 800-
831-3232; www.goline-x.com); and Rhino Linings (858-450-0441; www .rhinolinings.com).

Hunting-Rig Maintenance

outdoorlife-editor — Tue, 18 Sep 2007 12:26:32 -0400

Anyone who has purchased a new vehicle recently has seen maintenance intervals get progressively longer. To go 5,000 or 7,500 miles between oil changes is the norm these days, and it's not uncommon to log 50,000 or even 100,000 miles between tune-ups.

That kind of maintenance schedule is fine for a car that spends its life on clean, paved roads, but it could spell an early death for a heavily used hunting truck. Dirt, dust, mud and water all take their toll on engine and drivetrain components. You need a more proactive maintenance approach to keep your truck in top condition.

Fluids Come First

The simplest way to do this is to follow the "severe" or "heavy-duty" service intervals recommended in your owner's manual. Doing so increases the
frequency of critical fluid and filter changes, which is your first line of
defense against engine damage.

If your manual doesn't include a "severe" schedule, cut the "normal" schedule in half, or simply change your oil every 3,000 miles (or 2,500 miles for diesel engines). And don't forget to change the oil filter, or a quart of dirty oil will flow into your engine when you start it again. During the oil change, check all your fluid reservoirs and top off any that are low. If the air filter looks more than just dusty, replace it.
It's also important to drain, flush and refill your cooling system at least once a year, despite some manufacturer claims that longer intervals are acceptable. Mechanics tell horror stories about corrosion buildup and resultant engine component failure due to coolant left in the system too long.

Beyond the Engine

At oil-change time, check the condition of the drive-axle seals, especially if your truck has made frequent water crossings. A hot axle plunging into a cold stream can create a vacuum that can suck water right through the seals, and water intrusion will quickly contaminate the axle grease.

While you're under your truck, make sure the differential vent tubes are in good condition to keep water out of the axle housing. Also, remove any dirt or mud that has built up around the brakes, to keep grit from getting between the rotor and brake pads.

None of this is rocket science and it's not terribly time-consuming. Just consider the time you spend an investment in your truck's long-term health.

Water Hazards

outdoorlife-editor — Tue, 18 Sep 2007 12:26:31 -0400

During the winter and early spring months, there's a good chance your hunting rig is going to spend some time in the water, crossing storm-swollen streams or logging miles on rain- or snow-covered streets. Four-wheel-drives are very capable in wet conditions, but prolonged exposure to water can damage vulnerable drivetrain components unless you take the right precautionary measures.

Check the Depth

When you arrive at a water crossing, get out and check its depth first to make sure you won't swamp your truck. What was a shallow stream in the fall could be deceptively deep come spring if it's being fed by rainfall or melting snow.

How deep is too deep for your truck? A good rule is to stay out of
water that's deeper than bumper height, in order to keep the cab and, more important, the engine compartment dry. There's a lot under the hood that can be seriously damaged or destroyed if submerged, from ignition components and computers to the engine itself. Don't worry too much if your tailpipe is at or just below water level. Exiting exhaust gas should keep the water out.

If You're Dunked

If you find your engine compartment submerged, shut off the engine immediately. That should minimize damage from water being sucked into the cylinders. Once you're towed out, remove the spark plugs and turn over the engine so the pistons can push out any water through the plug holes.

Even during crossings at a safe depth, water can leak into wheel
bearings through worn or broken seals. Frequently inspecting your bearing seals can prevent freeze-ups caused by water leaking in and removing grease.

Water can also find its way down through the breather tubes that ventilate the transmission, transfer case and differential cases (the "pumpkins" in the axle housings) and contaminate the oil in those components. Differential or transfer-case gear oil turns from black to gray when contaminated, and transmission fluid goes from red to a frothy pink. In both cases contaminated fluids must be changed. If your rig is frequently in the water, you might want to extend the breather tubes beyond their factory length to keep water out.

If you find yourself regularly hood-deep, however, it's time to take more drastic measures, such as relocating your air intake through an external snorkel and protecting electrical components with watertight connections and containers. The boating industry also offers a wide array of waterproof engine and electrical components should you need a rig that's more swamp buggy than pickup truck.

Toyota Goes Full-size

outdoorlife-editor — Tue, 18 Sep 2007 12:26:31 -0400

In the full-size truck arena, size definitely matters. When it comes time to pack for a week-long hunting or fishing trip, who wants to worry about not having enough room for his buddies, his dogs and all his gear?
Size is one reason why some full-size truck buyers have previously shied away from the Toyota Tundra, a well-engineered vehicle that's slightly smaller (even in its
extended Access Cab trim) than the domestic half-tons. But not anymore.

Toyota's new four-door Tundra Double Cab is significantly taller and wider than other Tundra models and is also longer than some domestic pickups. Super-sizing the truck allowed Toyota to add nearly 9 inches of legroom and 1½ inches of hip room for rear-seat passengers. That means three of your friends (XXL variety included) will easily fit in the back seat, even if they're bundled up in bulky cold-weather gear.
While some four-door trucks gain cabin space at the expense of bed length, the Double Cab's 74.3-inch bed is generous, and longer than the bed on the Ford F-150 Super Crew. The Double Cab's bed walls are also taller, increasing the truck's cargo
volume and payload capacity by as much as 160 pounds for some models.

Yet towing capacity shrinks some. Why? Toyota grew the Double Cab's size and weight without a corresponding power increase. The Double Cab has the same 4.7-liter V-8 and four-speed automatic transmission as the other Tundras. The engine's 240 horsepower and 315 foot-pounds of torque are fine for the smaller trucks but just adequate for the Double Cab.

Size hasn't hurt the truck's road
handling, though. It still has the Tundra's smooth ride and precise steering, even when equipped with the firmer TRD Off-Road suspension package. You'll notice the extra length when
negotiating tight trails or an urban parking garage, but not on the open road.
We previewed the Tundra Double Cab several months prior to its launch, so prices had not been set. Toyota said the truck should be in the $28,000 to $32,000 neighborhood.

At a Glance: Toyota TUndra Double Cab 4x4 SR5

Fuel economy: EPA-rated 14 mpg city/16 mpg highway

Tow capacity: 6,500 pounds

Ground clearance: 11.2 inches

Engines available: 4.7-liter V-8

Major options: Vehicle Stability Control with TRAC traction control, TRD Off-Road package, limited slip differential

Base price/Price as tested: $30,000 (est.)/N/A

Chevy's Quadrasteer

outdoorlife-editor — Tue, 18 Sep 2007 12:26:30 -0400

Anyone who has tried to
finesse a full-size truck through a thick forest, down a twisting trail or even around a crowded parking lot will appreciate the new Quadrasteer option available on some 2003 Chevrolet Silverado pickups.
A steering rack on the rear axle controls the direction of the back wheels, steering them in a direction opposite the front wheels at low speeds, and in the same direction at highway speeds. The low-speed operation cuts the
Silverado's turning circle to a compact-sedan-like 37 feet, while the high-speed function increases stability during lane changes and other maneuvers.

A Trailer Puller's Dream

We found the low-speed mode particularly helpful, as the smaller turning
circle made this long-wheelbase truck more nimble than it used to be. If you pull a trailer, you'll like how the rear-steer feels on the highway, but be
prepared to practice backing up to get the hang of how the rear-steer moves the trailer tongue around.
Great innovations usually come at a price, however, and Quadrasteer is no exception. The "4-Wheel Steering Package" on the Silverado pickup we drove cost $5,715. Granted, that included heavy-duty trailering gear, a limited-slip rear differential and other equipment, but it's still a lot of money.

Quadrasteer's expanded availability (an option on 1500-Series extended-cab and Heavy Duty crew-cab models) is one of 40 changes Chevrolet made for 2003. Many of them-dual-zone climate controls, extra radio and computer buttons on the steering wheel, optional XM Satellite Radio-make driving easier and perhaps more comfortable, but they raise the truck's price without really improving its functionality. Luckily the truck's basic equipment doesn't need a lot of improvement.

The 5.3-liter Vortec V-8 is strong. Chevy's Autotrac transfer case offers a wide range of drive modes, including 2WD, full-time 4WD, and part-time 4WD in either high or low range. The independent front suspension gives the truck a smooth highway ride, and it does a good job of soaking up the bumps off-pavement.

In fact, one of the Chevy truck's strongest attributes is its ride comfort. GM's chassis engineers have tuned the truck's ride and handling to be tops in its class, making this a favorite for long-distance traveling.

Choosing Tires

outdoorlife-editor — Tue, 18 Sep 2007 12:26:30 -0400

Thanks to a continuing boom in light-truck sales, your
local tire store probably has a bewildering array of truck and SUV tires for sale. How do you choose a set that's right for your rig? Determining what kind of terrain your truck sees most often is key, but there are several other elements to keep in mind when tire shopping.

All-Terrain Advantage

All-terrain tires are a good choice for trucks that spend a lot of time on dirt roads or in the sand, or for those that see an even mix of dirt and pavement driving. An all-terrain tread pattern still presents a lot of rubber to road surface, but the tread blocks are aggressively cut into the tire, which gives the footprint lots of biting edges. The blocks aren't as big as those found on mud tires, so they will float over (rather than dig into) loose or sandy surfaces.

Because all-terrains are so popular, makers have developed a wide range of tread types that fall into this broad category. Yokohama's new Geolander A/T+, for example, combines
aggressively cut tread blocks on its shoulders with a center tread rib similar to that on a highway tire to put more rubber to the road. Goodyear's Wrangler GS-A has an asymmetrical tread pattern that changes across the tread's face from street-tire grooves on the outside shoulder to lug-like blocks on the inside shoulder.

If you're on the road most of the time, buy a highway-oriented tire with lots of rubber to meet the road and relatively thin grooves and voids. These tires provide maximum traction on the pavement and run quietly on the highway.

Max Mudders

For top traction on mud, loose dirt and rocks, and for trucks that see few pavement miles, the best tire is one with big, knobby tread blocks that dig into the ground. Wide grooves and channels allow these tires to self-clean as they spin so the biting edges don't get caked with mud and lose their grip.

The big tread blocks make them bad road tires, however. Those blocks squirm on the pavement, giving them mushy road contact and generating a tire's number-one enemy-heat buildup. The mudder's big voids also mean there's less rubber in contact with the road,
so there's less grip, plus mudders on pavement are very noisy.

For Those Who Tow

If you tow or haul heavy loads, pay particular attention to the tire's load rating. All tires have their load capacity ratings printed on the sidewall. If your truck is doing serious hauling duty, you should look into tires designated for light trucks (denoted with an "LT" in the size listed on the sidewall) rather than for passenger cars (P-metrics). An LT tire typically has stronger body cords, thicker plies in the carcass and belts that are more heavy duty than those on a passenger-car tire, giving the LT a higher load capacity, even if you're comparing tires of equal size.

In the Dunlop tire line, for example, an LT235/75R15 Radial Rover A/T has a maximum load capacity that's about 140 pounds higher than a P235/75R15 Radial Rover A/T fitted on a truck or SUV.

Is Bigger Better?

Bigger tires do have benefits: a larger footprint for increased traction, taller sidewalls for better ground clearance and a meatier appearance under the wheel wells. However, a taller tire changes your axle's final drive ratio, so acceleration will be negatively affected. That bigger footprint increases rolling resistance, which reduces fuel economy, as does the bigger tire's heavier weight. If the tire is too big, it will rub against fenders or frame rails, potentially damaging the tire and the sheet metal.

If you must have larger tires, be prepared to make other modifications-a suspension lift, spring and shock upgrades, fender flares, possibly a ring-and-pinion change-to accommodate the bigger meats.