Cold Weather Operation Considerations

When we refer to cold weather operation, we are referring to temperatures at or below 10 degrees farenheit. The further the thermometer plunges below 10 degrees, the more important these considerations become.

Don't Bust Your Butt or Freeze Your Butt

When you first step out of that truck after surviving that freezing rain or snow storm, you had better pay particular attention to your slippery truck steps while getting out. There have been many surprised truckers who slide off that familiar step which is now just a big chunk of ice. Hand holds on the outside of your truck may be surprisingly slippery as your hand slides off and your body falls out of control to the frozen pavement below!

Getting back into the truck can be just as risky. Watch those slippery hand holds and icy steps. Don't assume that the usual routine motions will result with you inside the truck!

The worst type of snow storm is the bitterly cold storm. This cold snow drifts quickly and can easily make highways impassable. While your rig is stuck in a snow storm and idling while the outside temperatures plunge below zero degrees, your fuel filters and or fuel lines can freeze up and leave you without a heat source. Make sure that you have blankets and/or an alternate heat source to keep the cab warm. In severe low temperature snow storms, there are no emergency vehicles; just remember that.

Of course, walking across that parking lot can be just as dangerous. Now that we have addressed things to protect your body, lets move on to things to protect your truck and keep it rolling.

Prevention of Frozen Brake Shoes

The tractor brake drums have dust covers installed on the inside of the brake foundation assembly. These dust covers also keep out water and freezing road slush. Some mechanics remove these dust covers and never replace them. This is not a good idea if you drive in cold weather climates.

While rolling down the road, the friction from your tires and wheel bearings, generate enough heat to keep the brake shoes from freezing. When you pull over and park, the water soaked brake shoes will freeze to the brake drums when the brake foundation temperature plummets below freezing. With the dust covers removed, the extra water and slush amplifies this problem.

There are two precautions you can take to reduce the likelihood of your brake shoes freezing to the drums. First you have to get rid of the water in the brake shoes. You do this by dragging your brakes for the last block or two of motion of your rig. This will generate brake friction heat which will help to evaporate the moisture in your brake shoes. After dragging your brakes for a short time, park your rig, and chock your wheels; then release your parking brakes. This will give the hot brakes a chance to evaporate the moisture within the brake shoes and on the brake drums. Allow sufficient time for the brakes to cool below freezing, and then apply the parking brakes and remove the chocks. Any remaining moisture on the brake shoes will freeze while not in contact with the brake drums. Therefore, although there may be frozen moisture on both the brake shoes and the brake drums, this moisture will freeze independent of each other, and are less likely to freeze together when the parking brakes are applied.

Any time you start up your rig after being parked in freezing conditions, remember to drag your brakes a little at the beginning. This will heat up the brake shoes and remove any glaze ice that may have formed on the drums or shoes. Your brakes will now work better the first time that you really need them.

Thawing Frozen Brake Shoes

OK, so you did not use the precautions recommended above, and now your rig won't move. You or a hired hand are going to have to thaw out your brake shoes before you can drive again. If you feel confident about doing it yourself, then the following procedures and warnings apply:

WARNING: When brakes are thawed out, the extreme force of the parking brake release air pressure will rip the frozen brake shoe from the drum. When this happens, the diaphragm push rod, slack adjuster, and brake camshaft will all move suddenly and with great force. Keep all body parts and clothing (gloves) clear of these components while the brakes are being thawed. Refer to the drawing above.

To thaw out your brakes you need a pair of good gloves, a propane torch, and a fire extinguisher. Oh yeah, you also need something to lay on, if your warm body on the frozen ground surface will melt the surface and get you wet.

WARNING: At all times, keep the torch flame pointed away from all fuel sources including oil seepage and grease seepage which may be caked on or near the brake foundation.

You simply chock your rig wheels are necessary, release the parking brake, and thaw out each brake shoe, one wheel at a time. It doesn't take a lot of heat to make the shoe release. So don't get carried away and never get things hotter than just above freezing. Move the heat around to slightly warm up all of the drum. Once all the brakes have released, set your parking brakes, remove your chocks, and get on down the road. Now you can thaw out your body while inside your warm truck cab.

Frozen Fuel Filters and Fuel Lines

While moving down the road, your diesel fuel injectors return unused fuel back to the tank. This circulation of fuel helps to keep moisture within your fuel filters and fuel lines from freezing. Once you shut down overnight, then the moisture present can freeze. Once again, the only remedy is to thaw out that frozen moisture. Most frozen fuel lines occur at the lowest point of the fuel line. If you feel confident about doing it yourself, then the following procedures and warnings apply:

WARNING: At all times, keep the torch flame pointed away from all fuel leaks, oil seepage and grease accumulation on nearby components. Never concentrate the heat, slowly move it around to raise the temperature of the entire filter. Use only enough heat to get the filter slightly above freezing.

To thaw out your fuel line or filter, you need a pair of good gloves, a propane torch, and a fire extinguisher. It doesn't take a lot of heat, so don't get carried away, and never get things hotter than just above freezing.

Keep Engine Temperature Normal

As the outside temperature drops, so does your engine water temperature. The colder it gets, the more your engine water temperature falls. Anything below 165-170 degrees farenheit starts to reduce engine efficiency and also reduces engine life.

Your engine was designed to run at about 180 degrees. At this temperature, all the machined parts including the cylinder rings are expanded to the correct dimensions, and are seated properly as the engine runs. When the engine temperature starts falling, the parts shrink in size and the mating tolerances go up. This reduces compression because the cylinder rings no longer fit properly.

The decrease in engine compression results in poor fuel burn and wasted engine efficiency. The increased blow-by forces more carbon and acids into the engine's oils supply, and these components increase lubricant friction which reduces the engine bearing life.

If you can't keep your temperature above 165-170 degrees, then cover the radiator to achieve these temperatures.

Greaseless Fifth-Wheel

During extreme cold weather operation, the roads are usually quite slippery in some locations if not all over. This means that your steering tires have less traction than normal. Now combine this with that molasses consistency grease between your fifth-wheel and the trailer. This grease can get really stiff at low temperatures. When this happens, the lowered traction of the steering tires coupled with this stiff grease, can delay or prevent tractor steering at unexpected times.

Some of the newer fifth-wheels include a Teflon insert built in (Jost fifth-wheel in picture). If you intend to do a lot of cold weather operation, and you don't have an insert built in, then you would be wise in purchasing one of those Teflon sheets which goes between the trailer and your fifth-wheel. One such product is the Polyglide® which features:

  • High impact strength
  • Durability
  • Greaseless
  • Environmentally friendly
  • Reduces fifth wheel wear
  • Effective in extreme temperatures (brittle point -54° C (-64.5° F)
  • Cost effective, reduces maintenance costs

Polyglide® has been a proven product, since 1987, used on semi-trailers allowing for ease in coupling and uncoupling by reducing the co-efficiency of friction. Polyglide® is used by both independent and fleet operators to reduce fifth wheel expense in a clean and environmentally friendly manner (Polyglide® is grease free).

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