Squeezing The Fuel Pump!
It is on all of our minds, how to stretch the buck to make our world livable in our chosen life style, that in, as Lucy calls it, “in tin boxes with wheels.” With addresses like, “where we stop,” and” general delivery.”
Now we have all heard the general fuel economy tips like the one espoused by our president elect, solve the energy crisis by buying a tire gage and properly inflating your tires, or just drive 55. But there is more and these are subtle changes in fuel economy that account for but pennies each. But as someone once said, and I think it was my mother who the truth be known was the actual person who ran our family garage, watch the pennies and the dollars will take care of themselves.
Take some time with your owners manual and read the oil recommended chart. The car and truck manufacturers spend a lot of time on that chart to make sure that it recommends the correct oil viscosity that will protect the engine and yet yield the maximum fuel economy. The thinner the oil the less resistance that it has to pumping meaning more power from the fuel is used to turn the wheels rather than pumping oil. This might mean a trip in to the weather channel site to get the average temperatures for an area that you might be heading for. The same thing goes for gear oil and wheel bearing lubricants.
Keeping accurate tank by tank fuel economy reading is a good check on all of the mechanical systems of your rig. We spotted a dragging car trailer brake in fuel economy readings. We dropped 2 miles per gallon on two successive fill ups. Something was wrong. But what? A hand held infra red pyrometer found the problem, checking drum and rotor temperatures at the next rest area stop. A quick repair and the next fill up showed the problem had been corrected.
Of course taking fuel economy reading on must take into consideration outside temperatures, wind, and road conditions. The surface of the road will change the fuel economy that you get. On the mechanical side, keeping all of the free play out of the steering joints, like tie rod ends, ball joints, king pins, and wheel bearings, will allow for a more precise toe in adjustments. The idea is to get the toe in as close to dead neutral straight ahead as possible. If the front end is tight a good alignment man should be able to set the toe at 1/16” in with the rig on the alignment rack. And it does not take a wiz bang laser guided missile machine to accomplish this, it is still up to the skill of the technician to turn the wrenches and make the adjustment.
When buying tires of course radials give better economy than bias ply tires. And a bit stiffer side wall will help handling and economy but be a bit rougher riding. However the biggest difference is the tread. The more aggressive the tread the more power it takes to turn the wheels on the pavement. But we still need the gaps in the tread to squish the water off the pavement when it is raining. This allows the tread to contact the surface. The trick is to get the gaps in the tread to run around the tire not across the tread. I call these types of tires highway design rather than all season. Ok, if you are using your RV for a ski chalet then all seasons or snow tires are a must, but for most of us who are RVing with time schedules, we car spend a few days waiting out a storm to save the extra pennies in fuel economy.
Stay tuned for another installment in “The Quest For The last Drop.”
Brad Sears