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Old 01-16-2018, 07:19 PM   #30 (permalink)
slowmover
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Join Date: Oct 2009
Location: Fort Worth, Texas
Posts: 2,442

2004 CTD - '04 DODGE RAM 2500 SLT
Team Cummins
90 day: 19.36 mpg (US)
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Quote:
Originally Posted by gumby79 View Post
Thats when you shake the leg of a sleeping passanger wille hitting the brakes and screaming..... LOL
I have found that drafting influences start about 1300' (1/4mi) to 2/3mi behind the large rig(RV , semi, bus) edpendent on how dirty the aero is on the lead rig. I showed Aerohead some videosof trucks,cars, and pickups w/ w/o trailers , that diminstrated how far back the draft works .
With my 1/3 -1/4 mile interval I find that I get sucked into the pack, when a truck travling at a slightly faster than the leader replaces me as rear gard.
I havenít tested for it, but it sounds interesting.

Iíve found that NOT passing (no lane changes; thus no related accel/decel events plus steering corrections) pays best.

On a known road (all conditions; familiarity) it is choice of a cruise control set speed just far enough below truck traffic that on a 700-mile day I may not pass more than one or two other vehicles. This is at about 62-mph. In the Kenworth.

When in the Dodge, whether or not Iím pulling the 35í travel trailer, 59-mph is best ďfastĒ speed for economy.

58-62/mph pretty well covers FE, and staying out of traffic. About all I need to do to get a 65-mph governed truck around me is to cancel cruise once heís in the passing lane. Drop back off to about 52. That gets him well out ahead of me in short order.

Manage the problems first by avoidance, second by shortening those remaining.

It also allows no real penalty with the assertive almost aggressive programming of my cruise control. Iím still far below the maximum weight expected for that pickup.

IOW, a set speed 2-mph slower means I donít have to cancel cruise as I would at a higher set speed to offset that assertiveness. That extra fuel. More work for no real gain.

As before, if one isnít using average mph as a tool for trip analysis, you havenít understood what I just wrote.

Use it

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