Fleet Fuel Saver Blog

Beware Clutter At The Rear Trailer Axle

admin — Fri, 26 Feb 2010 22:55:20 +0000

Trailer OEMs make design decisions favoring ease of assembly and maintenance access sometimes. Don’t let the position of hoses, air tanks and brake boxes at the bogey create additional wind drag for your trailer. Most of these components can be tucked up into the bogey frame itself, removing additional obstructions to oncoming air flow. This far back on a trailer, every item creating drag reduces MPGs significantly.

Consider Straight Mudflap Hanger Brackets for Trucks

admin — Mon, 29 Jun 2009 22:02:38 +0000

When you use angled hanger brackets for Class 8 truck flaps, you create the same effect for 30% or more of the flap that using stiffeners create. You restrict the top 1/3 of the mudflap from having any flexibility because it is anchored to the rigid angle design of the bracket. This is a critical area of wind drag on mudflaps at highway speeds, as the high speed jet of air that flows over the wheels and tires has significant impact on this upper portion of a solid mudflap. Consider changing over to straight brackets on the truck, and hanging those brackets slightly lower to clear any interference the angled brackets were designed to avoid.

Eliminate Steer Tire Mudflaps

admin — Mon, 29 Jun 2009 22:02:31 +0000

If you are putting high mileage on your rigs consistently week to week, you should look at removing steer tire flaps if you currently use them. No doubt they look good, and they help keep steps clear of mud and ice. These flaps however hang lower than anything else on the rig, catching the full force of oncoming air; and they represent another 2 square feet of surface area obstructing forward motion for the rig. Kenworth published information early in 2009 confirming that their steer tire flaps generate ½% reduction in fuel economy over the road. For a more aerodynamic profile, eliminate the use of steer tire flaps.

Remove Excess Flap Material

admin — Mon, 29 Jun 2009 22:02:16 +0000

If you substitute a longer mudflap for trailer use, and you recut mounting holes to cinch up the flap and shorten it to a more practical length, don’t forget to trim off the excess you create at the top of the flap. Once you remount the shortened flap, any material left above the hanger bar (3” to 4” typically) will drag serious wind in the path of the jet of air coming off the tires. Remember that correcting little things like this really adds up aerodynamically to improve fuel economy at highway speeds.

Increase Your Green Profile as a Fleet

admin — Fri, 22 May 2009 19:36:53 +0000

INCREASE YOUR SUSTAINABILITY/’GREEN PROFILE’ AS A FLEET. If you are an aspiring SmartWay partner, or are trying to meet certain sustainability or reduced emissions goals as a fleet, attacking the trailer mudflap wind drag issues is one of the fastest and cheapest ways to significantly reduce fuel usage.

Don’t Run With Extra Flaps

admin — Fri, 22 May 2009 19:36:18 +0000

DON’T RUN WITH EXTRA FLAPS. Tankers, in particular, have a tendency to use both truck flaps with front fender flaps on their tankers. One or the other will usually suffice. Operating with two extra flaps generates at least 1/3 more wind drag on the highway from the flaps. The same is true for flatbeds. If you don’t have to run with extra trailer flaps from a DOT standpoint, then don’t. The extra flaps cost another 2-3% reduction in overall fuel economy for the rig. If trucks have to bobtail at some point, and don’t usually run with flaps, store them securely like you do bad weather chains, behind the rear wall of the cab where they can be accessed and installed on the truck when required.

Eliminate Flap Stiffeners

admin — Fri, 22 May 2009 19:35:57 +0000

ELIMINATE ANY KIND OF FLAP STIFFENER. Mudflap wind drag costs enough fuel economy, don’t add insult to injury by trying to keep the flaps from blowing back at highway speeds. These stiffener accessories amplify the parachute effect of each flap, trapping just that much more wind and further reducing highway fuel economy.

Don’t Build a Wall to Protect Leyman Liftgates

admin — Fri, 22 May 2009 19:35:36 +0000

DON’T BUILD A ‘WALL’ TO PROTECT LEYMAN (or similar undercarriage) LIFTGATES. Many food distributors operate liftgates that are extremely tempermental when electrical wiring and connectors get exposed to water and road spray. Their home remedy many times is to block the front of the liftgate with a series of solid flaps to redirect water away from the electrical connectors. Several fleets have reported losing 1.0+ MPG when they erected this wall in the undercarriage of the trailer.

Don’t Block the ICC Bar

admin — Fri, 22 May 2009 19:35:00 +0000

DON’T BLOCK THE ICC BAR. The greatest wind drag and turbulence on a Class 8 rig occurs right at the ICC bar. High speed air is flowing through the undercarriage of the trailer, and anything that it slams into at the back of the rig amplifies the reduction of fuel economy. License plates, solid steel plates or struts from the deck to the ICC bar, haz mat signs strung in that same gap, storage boxes and mudflaps are all “no-no’s” that should be avoided if you are spending significant miles on the highway. All of these obstructions pull down fuel economy by 0.3 to 0.4 MPG. If you have to hang something right at the back of the trailer, try to position it so the ‘into the wind’ profile is the smallest possible, and somewhat aerodynamic in shape so it cuts the wind, instead of blocking it.

Eleminate Cow Mats

admin — Fri, 22 May 2009 19:34:32 +0000

ELIMINATE ‘COW MATS’. Many drivers like to use extremely heavy and thick ‘cow mats’ as trailer flaps. These don’t blow back in high speed winds, but as a result they lower fuel economy by 0.6 to 0.8 MPG. That fuel bill is an extra $4,000 per year out of your pocket.