Technical > Four Wheel Finesse
Forgotten Maintenance Items That Can Bite You in the Butt on the Trail
by Jim Allen
Frequent floater mileage creates many maintenance chores. In a perfect world, all those parts under water are sealed against water ingress. In fact, some water almost always finds its way into a drivetrain. In many cases, the small amounts can be evaporated via heat, but that doesn’t get the silt out. Best advice: If you do this a lot, change drivetrain oil once a year or as necessary.
There’s nothing like having your ego and reputation destroyed on the trail when something goes snap, crackle, or pop — and you find it could have been avoided by maintenance. Whoops! There’s not too much to do at that point but turn red, look down and shuffle your feet, and vow to never let it happen again. Let’s talk about the common things people miss that come back to bite ‘em in the butt.
Anyone who’s been on more than a few runs has seen people hit the trail with a known problem hoping and praying that it won’t take a mouthful of glute (gluteus maximus, a.k.a. butt) — an example of ego and poor judgment overcoming common sense and responsibility. The universe will sometimes let a person skate, but most often they end up with teeth marks. Anyone who’s been there, including me, will tell you that, to avoid the stress and strain on your rep, take care of known problems first. Miss the trail run if you must. To use the old adage: Take care of your rig and it will take care of you.
Drivetrain
Universal Joints:
Some rigs use greaseable joints and some do not. You can get some reputation leeway if a factory non-greaseable joint fails when the lube goes dry or is contaminated, but if it has a Zerk fitting, you’re busted! According to most driveline guys, greaseable joints — properly and regularly lubed-will generally outlast the non-greaseable types by a wide margin, and you can usually purge them of contaminants. And before you bring it up, the myth that non-greaseable joints are significantly stronger than greaseable is just that, a myth. If you do install a non-greaseable joint, though, pack it with the best grease available at installation to help it last longer. Always use the best grease available for u-joints.
Differentials:
If you wheel a lot in mud or water, you’ll need to change the gear oils a lot more often. Water can enter an axle in many ways. One of the most common is the inhale syndrome. When a hot axle is put into cool water, the air inside rapidly contracts, and the axle goes from a slight positive pressure to negative pressure. If the breather is restricted or if there’s a particularly weak seal, it can actually suck in water past the seal lip. When you’re stuck in a watery mud hole, water can sometimes seep past seals. In small amounts, the water can be evaporated by heat. Large amounts destroy the oil’s ability to lubricate. Water often carries abrasive silt. Bottom line, change gear oils at least once a year or as often as necessary.
Packing wheel bearings isn’t fun, but having a wheel and hub part company with a vehicle is less fun. Some rigs, like the Ford Ranger, have hubs that aren’t well sealed against water. Steps can be taken to improve this, but until you take them, there are two choices: keep the hubs out of the water, or pack the wheel bearings after each long bath.
Wheel Bearings:
Once a significant amount of water gets into a wheel-bearing hub, it’s in there to stay, and it’ll ruin the grease. In a fairly short time, a mass of rusty goo collects in the hub and the wheel bearings corrode into scrap. If the wet stuff is hit often, plan an annual wheel-bearing pack/inspection, if not more frequent service as indicated, just as with differential oil. Even the so-called “sealed” bearings can allow water in, but that’s beyond your control. All you can do is pay attention and replace a bearing when it gets growlly.
Automatic Transmissions:
Famous last words: “It’s slips a little in third gear, but it’ll make it after I change the fluid.” A tranny that’s slipping is the automotive equivalent of a dead man walking. Changing the fluid is an intuitive thing, but often kills the tranny even faster. Do fluid changes early and before the tranny is dying. A hard-worked trail automatic can get hot, so more frequent fluid changes are necessary. Figure on about every 15,000 miles. When the fluid starts to get dark, that means it’s been getting hot. Change it before it gets a dark cherry-juice look.
Engine/Electrical
Cooling System:
Nothing’s worse than being on the trail with a guy who has to stop every 15 minutes to tend a radiator that’s vomiting coolant. While having a radiator that’s too small after an engine swap is a trail faux pas, poor maintenance is the trail equivalent of passing gas in an elevator. I could go on for pages here about partially plugged radiators, bad caps, not enough coolant, bad thermostats, weak fan clutches, slipping belts, collapsed hoses, wobbly water pumps and blocked airflow out on the trail, but I won’t.
Belts:
There’s no excuse for failure when a belt is cracked and dried up like an Egyptian mummy’s favorite galoshes.
Batteries:
Ancient, bearded batteries in their death throes, corroded into a blob of white goo, tied down with a rotted bungie cord, or too small for the job have no place on the trail.
Tires
Worn:
Not only is a worn tire useless in the traction department-it makes a rig struggle on the trail — but it’s more vulnerable to damage.
Too Big:
Tires too big cause drivetrain breakage, rub against body parts, and can be cut or damaged as a result.
Suspension & Steering
Power Steering:
Especially after big tires are installed, power steering will get a workout and the fluid can get hot. The fluid used in power steering is hydraulic fluid similar to automatic transmission fluid, and it breaks down with heat. This can cause loss of power assist and boiling over in the short term and component failure in the long. Change power-steering fluid once a year if you wheel a lot, especially for rock crawling, and mount tires much larger than stock.
Steering Linkage/Ball Joints:
Many suspension ball joints and tie-rod ends on newer rigs do not have Zerk fittings, but older ones do as well as many aftermarket replacements. Just like a u-joint, these ball-and-socket joints can collect water and fail. If greased regularly, they not only get lubricated, but also purged of contaminants. It’s one thing to have a u-joint fail and strand you. It’s another to lose your steering. Lube them often, especially after a wet or dirty bout of wheeling.
You can pick up all the parts you need for maintenance at www.4wheelparts.com or a 4 Wheel Parts superstore near you.