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slowmover · 10-18-2014, 08:41 AM

Thanks, Bob, for the reply.

I've been slow to do much with truck and/or travel trailer due to very long days in oilfield, but am heartened by what you report in re truck aero effects on trailer (better, on the combined rig). While there is the approach that would use the tow vehicle to present a "spoiler" to channel wind over the travel trailer, my reading and hunch has been that treating each vehicle separately is the better approach (for me) as the miles under tow are dwarfed by solo miles. The gap between the two and the width discrepancy are large, in most instances, of tow vehicle and travel trailer (read: trailer with large frontal area).

Whether such effects can be quantified is one thing, but I'll rely on others when it would appear that the trailed vehicle is having a slightly easier time . . thus, perhaps, having less effect on the tow vehicle as "seen" at the steering wheel (where the ideal is least effect at the rear axle; this more a matter of proper lash-up)). If this is sort of chopping the peaks off a graphed up/down series of inputs, then the aero work on the tow vehicle is a success (as I see it). Others are welcome to think on "confirmation bias", et. al. with my comments; so be it. I do not discount good reports of small vortex generators at the tail end of 53' box vans as being fanciful, either. Grist for the mill.

I am firmly of the opinion -- as a truck driver -- that a driver in command of a vehicle even somewhat more impervious to winds is more likely to be able to exert fine motor skills effectively throughout the day to attend to drivetrain use smoothly.. Graduated responses, not gross. Timing, duration, pressure, etc. A rested man is better than one who is tiring a bit faster as things go along, etc.

If such is the case, then the heavy-duty simplicity and utility of your bed cover mitigates more fastidious attempts at "best". The crosswind-handling problem is ever-present with a pickup and my experience with a standard cab-height topper exaggerates (seemingly increases) the length of the vehicle. I am quite aware of forces fore and aft versus the "central" push experienced by a car. The force redoubles over the length of the vehicle, IOW, with the sail area increase of a standard bed topper.

A high average mpg (yours is slightly better than mine, now, with a more challenging vehicle spec and climate, perhaps even terrain, congratulations!!) coupled to possible better towing behavior is genuine "win".

The variety of approaches here, and the long-term reports, make reading this forum always fruitful for ones thinking.

As always, I take time along the way to read your posts on TDR and CF even if I don't post much.

Best

.

10-18-2014, 08:41 AM	#36 (permalink)
slowmover Banned 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) Thanks: 1,422 Thanked 737 Times in 557 Posts	Thanks, Bob, for the reply. I've been slow to do much with truck and/or travel trailer due to very long days in oilfield, but am heartened by what you report in re truck aero effects on trailer (better, on the combined rig). While there is the approach that would use the tow vehicle to present a "spoiler" to channel wind over the travel trailer, my reading and hunch has been that treating each vehicle separately is the better approach (for me) as the miles under tow are dwarfed by solo miles. The gap between the two and the width discrepancy are large, in most instances, of tow vehicle and travel trailer (read: trailer with large frontal area). Whether such effects can be quantified is one thing, but I'll rely on others when it would appear that the trailed vehicle is having a slightly easier time . . thus, perhaps, having less effect on the tow vehicle as "seen" at the steering wheel (where the ideal is least effect at the rear axle; this more a matter of proper lash-up)). If this is sort of chopping the peaks off a graphed up/down series of inputs, then the aero work on the tow vehicle is a success (as I see it). Others are welcome to think on "confirmation bias", et. al. with my comments; so be it. I do not discount good reports of small vortex generators at the tail end of 53' box vans as being fanciful, either. Grist for the mill. I am firmly of the opinion -- as a truck driver -- that a driver in command of a vehicle even somewhat more impervious to winds is more likely to be able to exert fine motor skills effectively throughout the day to attend to drivetrain use smoothly.. Graduated responses, not gross. Timing, duration, pressure, etc. A rested man is better than one who is tiring a bit faster as things go along, etc. If such is the case, then the heavy-duty simplicity and utility of your bed cover mitigates more fastidious attempts at "best". The crosswind-handling problem is ever-present with a pickup and my experience with a standard cab-height topper exaggerates (seemingly increases) the length of the vehicle. I am quite aware of forces fore and aft versus the "central" push experienced by a car. The force redoubles over the length of the vehicle, IOW, with the sail area increase of a standard bed topper. A high average mpg (yours is slightly better than mine, now, with a more challenging vehicle spec and climate, perhaps even terrain, congratulations!!) coupled to possible better towing behavior is genuine "win". The variety of approaches here, and the long-term reports, make reading this forum always fruitful for ones thinking. As always, I take time along the way to read your posts on TDR and CF even if I don't post much. Best .