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slowmover · 08-23-2011, 12:30 PM

Thanks for the info. There are some very good discussions on AIR about trailer construction materials for the interior, floor, insulation, etc, that may be of interest to you. Nyloboard is one: as subfloor; weighs more but is rotproof and may have better dimensional stability than marine plywood or OSB (Advantech). Same for some honeycomb materials that are lighter.

There's a trade-off somewhere with weight and aero, but I don't know where it is (converging lines on a graph). Given that one is not in mountainous terrain constantly, or in stop-n-go traffic, the "weight penalty" doesn't mean much inside some parameters the truck can live with in re weight as one runs the roads (mainly gearing and engine power graphs). If you hit 6k, great, but I sure wouldn't sweat 7,500-lbs as the final result as I really (really) think it won't make much difference.

On mine (305/555) there just isn't much difference from 9k to 11k for a given rig. Or, from 6k to 8k. (The latter set is only slightly better). The "killer" on the former is that it is getting up to factory recommended limits (conventional pull), thus any stops exact a telling penalty. On-highway it is almost nil (in generally level terrain) overall, given one is at a happy rpm. A change to 4.10 would take care of it were another set of gears for the NV-5600 available. Or a seven speed with two overdrive choices.

Gotta love a Cummins with a turbocharger!!

Have you finalized the truck spec for a given combination weight? A man trans might widen the performance envelope with a rear gear change, for instance.

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08-23-2011, 12:30 PM	#4 (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 for the info. There are some very good discussions on AIR about trailer construction materials for the interior, floor, insulation, etc, that may be of interest to you. Nyloboard is one: as subfloor; weighs more but is rotproof and may have better dimensional stability than marine plywood or OSB (Advantech). Same for some honeycomb materials that are lighter. There's a trade-off somewhere with weight and aero, but I don't know where it is (converging lines on a graph). Given that one is not in mountainous terrain constantly, or in stop-n-go traffic, the "weight penalty" doesn't mean much inside some parameters the truck can live with in re weight as one runs the roads (mainly gearing and engine power graphs). If you hit 6k, great, but I sure wouldn't sweat 7,500-lbs as the final result as I really (really) think it won't make much difference. On mine (305/555) there just isn't much difference from 9k to 11k for a given rig. Or, from 6k to 8k. (The latter set is only slightly better). The "killer" on the former is that it is getting up to factory recommended limits (conventional pull), thus any stops exact a telling penalty. On-highway it is almost nil (in generally level terrain) overall, given one is at a happy rpm. A change to 4.10 would take care of it were another set of gears for the NV-5600 available. Or a seven speed with two overdrive choices. Gotta love a Cummins with a turbocharger!! Have you finalized the truck spec for a given combination weight? A man trans might widen the performance envelope with a rear gear change, for instance. . Last edited by slowmover; 08-23-2011 at 12:37 PM..