Fiberglass vs. Aluminum mpg's

roadrider10 wrote:
Did the aluminum sided trailer have an enclosed bottom. I suspect the Cougar does. Manufacturers claim that helps. I have a Laredo with a similar fiberglass front to the Cougar and an enclosed bottom. I get about the same mileage as my previous trailer without those features which was much lighter. I suspect the mileage difference may have been due more to environmental conditions though.

Yes, the Catalina has an enclosed underbelly.

Did the aluminum sided trailer have an enclosed bottom. I suspect the Cougar does. Manufacturers claim that helps. I have a Laredo with a similar fiberglass front to the Cougar and an enclosed bottom. I get about the same mileage as my previous trailer without those features which was much lighter. I suspect the mileage difference may have been due more to environmental conditions though.

It doesn't take much of a tailwind to improve the MPGS.

People here often state that slowing down 10 MPH increases MPGs dramatically.
A 10 MPH tailwind will have the same effect, yet be unnoticeable to the driver while moving.

I really doubt that the front cap design has anything to do with it as that area is really turbulent, If it were the leading edge of the lashup, running in clean undisturbed air, than it may make SOME difference

There have been posts in the past by RV delivery haulers, who said that from best to worst mpg, the order is fifth wheels, filon trailers, aluminum trailers.

I would think the shape along the front of the TT would have the most influence on MPG.

The painted aluminum sided trailers are lighter than their fibreglass equivalents .
the last time i shopped for a trailer i took my time .
i had a 36 foot beaver mh and previously had owned a 27 ' slideout , and a nomad 1661 .
at the time Nash offered a 22GQ model in 3 different configurations .
aluminum sided Nash 3567 # on the axles .
fibreglass sided Arctic Fox 4380 # on the axles
fibreglass sided Nash 4180 # on the axles .
all 3 were the same floor plan.
at that time i had already done a couple of extended road trips and decided i wanted a heavy duty pickup towing an efficient trailer .
i really focused on build construction , load capacity , tank capacities , etc . as i expected to haul this thing many miles .
hence the study between the 3 .
instead i purchased a similar model from Komfort a 21T that was the same size as the 22GQ but had a much thicker frame , bigger tanks , and a few more features .
but i did learn that the fibreglass added to total weight and because the tires were the same the aluminum sided trailer had more payload capacity .

Robby9 wrote:
Francesca,
Those are the two TT's in question. The Catalina is a 2012 that is going to an early grave due to hail. The Cougar is a 2013. The nose may be the difference. There is very little gap between the tailgate of the truck and the front of the Cougar.

I think that's it, all right. Too bad about the Catalina...and what a sweet nose job on that Cougar!

Wonder when they'll start in with belly skirts and tail deflectors like the longhaul trucks are starting to add for fuel economy...interesting to watch the changes!

Francesca,
Those are the two TT's in question. The Catalina is a 2012 that is going to an early grave due to hail. The Cougar is a 2013. The nose may be the difference. There is very little gap between the tailgate of the truck and the front of the Cougar.

Robby9 wrote:
My new fiberglass TT is 2' longer and 600lbs heavier than my former aluminum sided TT. (the old rig did have a rounded fiberglass front.) On a 400 mile trip this weekend I got 1 mpg better than usual. I've read that smooth fiberglass gets better mileage, but I didn't really believe it.

You were smart NOT to believe it. You can NEVER do any direct trip to trip comparisons since no two trips are EVER the same weather, same traffic etc. ANY of those tings could easily make more than a single MPG difference.

you have to add with most fiberglass upgrades also include better, stronger tires.

Whole trailer is stiffer and doesnt flex so much while in motion.