Guardrail

Find my semi and do that and you'll likely end up with a windshield full of grit. Truck drivers do not like tailgaters!!

bbhzx12

Gee, I wonder why they travel in convoys whenever possible then? Pick up a CB at radio shack, truckers hate 4-wheelers they could care less about a truck and trailer behind them.

Guardrail

Only the dumb ones travel in convoys. I don't hate stupid 4-wheelers any more than I hate stupid truck drivers. (trust me, there's a lot of the truck driver variety) It's always best to keep your distance from trucks.

If you follow a truck close enough to catch the draft you won't be able to see what is going on down the road. You also might catch anything that is flipped up by the trailer; tire retread, board, rock, you get the idea.

I respect each vehicle for the driving ability that they display. If they act stupid around me, they aren't going to get any respect from me.

Scotty

I tucked in behind a semi when I was in a snowstorm, I had a CB and asked him if it was ok and the answer was yes and thanks for letting him know.
We were only going 30 mph and the only ones on the road.

I agree, theres more crud that can come off the tires then most folks realize.

I watched a tailgater on a semi one day and heard on the CB that he could not see them behind him unless he swerved a bit. Well, one swerve put the trailer tires on the shoulder and the brakes went on real fast. Luckily I was far enough back to avoid the panic stopper.

I bet the truckers can tell if someone is in their slip stream as their truck will feel the drag of pulling whats right behind them. I know I can feel it if someone gets in behind me with a trailer or a semi...kinda like hitting a grade.
Boost and pyro show it too.

Scotty

thumper 549

....Well,I ams a dumb trucker and I will not let you get that close to me as it is risking your life....I haul all Oversize stuffff and you never know when something might come off, the further you stay away from a truck the longer you might live....not to mention brand new tires that fly apart much lees recaps, think about it........most out there are driving for some one in today's world....not their own truck, they do not know what the last driver ran over,whats tied dwn etc etc

Superduty

http://www.everytime.cummins.com/eve...Whitepaper.pdf

Find the line about truck/trailer separation.

The front on your trailer is ribbed aluminum, right ? I think that is terrible for aerodynamics.

IsItFast

Interesting read Superduty.

Guardrail

That's what I was referring to, thanks.

Lurch519

Whar about the "bubbles" that are on the front of semi-truck trailers that are really tall ? I would think that if you cannot put a camper shell on your truck because of the load, then a fiberglass hemisphere will help divert the air around the front of the trailer. What kind/type of tire are you running on those 22.5 rims ?

induchman

There's part your problem right there. Slowing down to 65 will vastly improve your mileage.


Any fiver, except maybe a Teton or Alpha will have less resistance. I only excuse those two because they're oversize. My 36ft horse trailers are even more streamlined than Fiver Bob's rig. They are lower, narrower and don't have that huge bedroom overhang. Plus when I'm not hauling calves, I can put two Wranglers in there end to end!

P Kennedy

IsItFast you keep defending your truck as not the problem and several truckers with experience have tried to enlighten you. I read carefully everything you wrote and analyzed it. #1 it was stated the gap between tow unit and trailer has a limit, optimally less than 24"= full size truck topper with elevating planes to maintain air flow to rise above the initial vertical edge (front of trailer). #2 your gear ratio with the tires is WRONG for pulling in high gear, this can be proven very easily with a manifold(turbo boost) guage which will show that in order to maintain the speed(s) you are towing the pressure will be maximum or close to it all the time.This condition would be equivelant to a semi on a slight grade or crosswind where it is necessary to have close to or maximum fuel (throttle on floor) to mantain any speed. Wind resistance+maximum torque to maintain speed+low side of horse power curve= poor towing capability and poor fuel milage. POSITIVE side to all this is best possible break in of a new engine by maintaing consistant maximum water temps to seat and stabilize the engine components. Answer to problem is tow in 5th gear and increase RPM= same or better fuel milage and more available HP. Lack of aerodynamics creating excessive wind resistance combined with poor gearing, improper driving technique have created a condition similar to towing 30-35,000lbs continuously-5-8mpg normal. Be honest with yourself, look at the bug line on the trailer if it is any lower than 12" down the front vertical edge you have excessive frontal wind resistance. B5.9 Cummins Series III peak torque 1950-2200 rpm, peak horse power 2450-2700 rpm. Is it the truck or trailer??????? PK

herb

http://www.2wtd.com/air-flow_air-def...pecs-info1.htm

Superduty

"B5.9 Cummins Series III peak torque 1950-2200 rpm"

It is actually 1600 RPM for a 3rd gen.

P Kennedy

Your right my mistake I was looking at a marine 315hp spec at the time, however point being the same it is hard to get maximum fuel economy towing with your tootsies hanging out the firewall. Manifold pressure guage used properly tells more than when the turbo is singing. I think Hohn or Scotty has guages and can give this fellow an average manifold PSI towing for a reference point. PK

supr

I do not think there is anything you can do for the money to improve your aero, especially at that speed. So, if you are not worried about MPG, why worry about aero?
I can get 13+ with my tall Alfa at 55-60.
A little math: Going 300 miles at 60, 5 hours; at 80, 3.75 hrs. Gain, 1.25 hours. Mileage drop, 4+ MPG. 300 miles @ 12 mpg, 25 gal. 300 mi at 7.5 mpg, 40 gal. 15 gal diff @ $2.50/gal= $37.50 to save 1.25 hours.
Let's not forget what a ticket might cost, not to mention safety. If your rig starts getting squirrelly, it may take you to a destination where it costs a LOT.
Blown tire at 80 with a trailer?
Leave a little earlier, save money, no tickets, maybe save you & your rig. Maybe someone else if you take then out.
Maybe you should ask is there any good reason to go that fast?
I think the potential downsides are too great, physics be dammed.