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Old 09-05-2019, 12:46 PM   #21 (permalink)
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Originally Posted by Piotrsko View Post
Not doing that bad, you're just below my "retired"18 mpg average in city with a 6 speed driving like an old man with a hat.

Check your calipers for drag after release, they're famous for that, my rr is showing signs.
That funny you mentioned it. I did re do my brakes in 2016 when I bought the truck. needed rotors and pads very badly and I cleaned/greased the caliper slide pins. I do check brakes every 5k when I change the oil/rotate the tires. I haven't seen above 19mpg in a while though. I got 19.5 with stock tires and no front leveling kit. but the tonneau cover helped more than I ever thought.


Does anyone have any data on those roof mounted wind deflectors? see them on big rigs but rarely on trucks pulling 5th wheels. I could fabricate one pretty easily and anyone can ask my wife I don't give a rats butt about what others think my truck looks like lol. shes nearly pristine for 20 yrs old.

I was thinking the wind deflector on my roof because the side my side may sit 1.5 higher on even my new trailer etc.

I didn't know how valid the picture attachment really was etc.


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Old 09-05-2019, 01:48 PM   #22 (permalink)
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I'm pretty sure (BamZipPow or Aerohead will likely chime in if I'm wrong) that the airflow leaving the trailer is just as, if not more, important than the airflow hitting the front of the trailer. A slanted front will help, but a properly angled rear will likely help more.
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Old 09-06-2019, 01:07 AM   #23 (permalink)
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anyone can ask my wife I don't give a rats butt about what others think my truck looks like lol. shes nearly pristine for 20 yrs old.
There's a joke in there somewhere.

The tow vehicle deflector likely doesn't apply to your situation. I'm still waiting to see what this looks like. If it's a UTV on a flatbed trailer, the best bet would be pontoon fenders on the trailer and a boat tail on the UTV. Maybe a tarp over the nose of the UTV to smoothen it.
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Old 09-06-2019, 05:50 AM   #24 (permalink)
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These pickups are known for being heavily biased to the undersized front brakes. 2 decent brake applications while towing can warp the rotors
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Old 09-07-2019, 12:20 PM   #25 (permalink)
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Quote:
Originally Posted by justinooo9 View Post
That funny you mentioned it. I did re do my brakes in 2016 when I bought the truck. needed rotors and pads very badly and I cleaned/greased the caliper slide pins. I do check brakes every 5k when I change the oil/rotate the tires. I haven't seen above 19mpg in a while though. I got 19.5 with stock tires and no front leveling kit. but the tonneau cover helped more than I ever thought.


Does anyone have any data on those roof mounted wind deflectors? see them on big rigs but rarely on trucks pulling 5th wheels. I could fabricate one pretty easily and anyone can ask my wife I don't give a rats butt about what others think my truck looks like lol. shes nearly pristine for 20 yrs old.

I was thinking the wind deflector on my roof because the side my side may sit 1.5 higher on even my new trailer etc.

I didn't know how valid the picture attachment really was etc.
The original source included the drag coefficients for each configuration.I have it at PhotoBucket,but can no longer access any of it.
As to the deflectors,they need to be tuned,and do not lend themselves to just shooting from the hip.
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Old 09-09-2019, 11:42 PM   #26 (permalink)
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I think you are right. I spent 10yrs through the military in CA and their truck speed limits apply to anyone with a added tow axel so I got used to that. There are very few roads in my area with a less than 65mph speed limit so im not gonna be that guy and constantly have to pull over to only get 2ish mpg more max with my truck. I do slow down for hills, take it slow on corners when necessary etc. Ive been towing equipment and trailers up to 48ft for good amount of time so I feel my driving is pretty conservative esp when loaded.



agree with the truck speed limit. Old habit from a bad state I spent a good amount of time in. I usually do go over 65 loaded anywhere just because of the added fuel consumption but 65 in the areas I drive seem to be the right blend of keeping people off my tail, keeping good distance from those ahead of me, sometimes I can even time traffic lights in congested areas but most of the time they fly around/ then in front of me so I just stay back and let them fight for the seconds saved lol.

Im gonna do some more work on the trailer tonight. May even be able to load the side by side on it to take some measurments. Probably next week the unit will be 100% though. Appreciate the info/thoughts. hoping to post a pic for your input soon.
I speed up before the hill upwards 90 miles an hour by the time i crest the hill i'm doing 60mph while keeping in 4th gear in the MPG band( accelerating up hill uses more gas then accelerating down hill or flat)


this will not work for trailer since most of the time the load is unstable over 70mph
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Old 09-10-2019, 05:17 AM   #27 (permalink)
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Trailer tongue weight (measured; bathroom scale method) MUST be 10% or greater. Stability is dependent.

62-64/mph is more than fast enough. Keeps one out of the left lane. The new challenge is to manage overtaking traffic that they spend the least amount of time alongside.

State law prescribes weight limit for non-braked trailers. Must know weight. Brake actuation must be verified, and the controller set to engage HARDER than the tow vehicle. (TEKONSHA P3 controller minimum acceptable).

The test is that the combined Rig stops FASTER than the tow vehicle while solo.

Find the brake controller setting that does this with the hardest FULL stop AND least amount of trailer tire flat-spotting. (Test again on gravel or dirt).

Find the roads you can do these. It’s not an option. It’s basic. Same with the tongue weight percentage. BOTH need to be “working” to ensure trailer stability.

The contact patch of the trucks rear tires is the emergency allowance. Thus they CANNOT be overinflated. Use a CAT SCALE to get weights with and without trailer, max fuel as you arrive, and with all passengers aboard both times. Consult the Load & Pressure Table for that tire rating and NAIL it down.

A pickup is one lousy tow vehicle. High center of gravity and crippled steering & handling. It’ll roll where a car would spin. MUST reduce hazard. Tongue weight, brake actuation, and tire pressure are basic. (Trailer tires set to maximum).

Knowing ALL weights is a baseline record. Ideally the DRIVE Axle is heavier than the Steer Axle by 10% or greater when Towing. BEFORE one is hitched.

The weight in the truck bed must:

1). Be either atop or Forward of the Drive Axle; and,
2). All gear MUST be secured that in the event of a rollover that none of it comes out of the bed.

Yes, it’s all part of FE. Reduced steering corrections (input PLUS degree thereof) is so serious that both Cummins and Kenworth cite it in their literature.

Driver fatigue affects us all. Please DONT tell yourself you’re better than others at this. First, I’m better yet. So what? The RANGE of skill between all is so small as to be irrelevant. Second, what matters are those moments of inattention to which we are all prone. (Why steady-state on cruise control BELOW commercial traffic is a winner as fatigue takes its toll. No one is exempt). The later in the trip, the greater likelihood of a problem.

TRAILER AERO matters most with ability to handle cross-winds. The lower the profile, the better. Unequal braking action has aero consequences, as does bad trailer axle alignment. (First clue is shot leaf spring bushings; check them).

The gap between the pickup and the trailer is the source of most “bad” aero penalties. But hardest to fix. A deflector MAY help but is as likely to hurt (as Phil noted above).

Ford I-Beam front axle is your aero concern. Zero steering slop ATOP perfect alignment. My 1T has IFS with rack & pinion steering. Which of our trucks will require fewer inputs, brand-new? Which will EASILY surpass the THREE SECOND RULE of releasing the steering wheel and the truck DOESNT head for the ditch?

We don’t want the trailer to wander. At all. We want it “locked” to the tow vehicle. (I can follow you and video the wander. Chances are it will spend the least amount of time in alignment).

As the FORD steering gear type and front end slop baked-in by design gives TERRIBLE feel for what the trailer is doing, it will be too late by the time it’s felt.

Both vehicles can use new Shock absorbers (past 60k on pickup; get BILSTEIN air KONI) and the LIPPERT kit for the trailer. Otherwise, the tires must do two jobs, and this is what will get it sideways. Crow-hop. Shocks are insurance to keeping the tow vehicle tire contact patch undisturbed .

Loss-of-control can come with road surface camber changes, tripping hazards, and slick surfaces. We want EACH tire to maximize grip. Won’t happen with dead or non-existent shocks.

And these corrections makes a long day at the wheel easier. Least amount of I put to maintain headway. Which in turn makes traffic management less onerous. Which in turn means greater alertness throughout the trip.

Whatever the rig, it’ll come back to operator awareness. Don’t think you’ll overcome Rig deficiencies by brute force.

Awareness is diminished with higher speeds. It is NEVER acceptable to be surrounded by others. Cancel cruise and let the idiots sort themselves. Etc.

The vision problem INCREASES with greater speed. Peripheral awareness decreases radically. The “cone of awareness “ shrinks to what’s in front of one.

Too fast if you aren’t aware of changes in the land as they appear. Grasses, soil, etc.

We ease along, manage the idiots to get gone, and reserve our strength.

The framework for this is to execute legs of a trip. One waypoint to another. Plan the stops (same direction of travel, fewest steering inputs to park and then depart, etc). Two hours between breaks is a professional rule. At four hours need a one hour break.

This is how you keep your actions consistent.

Aero is HIGHLY dependent on discipline. The discipline of a higher state of mechanical condition, and the discipline of rules by which to drive. “All cruise control, all the time”, is that example (as too high a speed relative to traffic cuts into it; changing lanes one must cancel it; overtaking too much traffic means cancellation, etc).

There’s a sweet spot in all things: Lane-centered at a dead-steady speed, is where it happens. (Not otherwise).

Now. How embarrassed would you be if I slid into the drivers seat of your truck and proceeded to get better MPG than you? All as above. No differences in rules. A rig I’ve never driven. (I run away from Fords. �� ).

The difference between us is that I’ve been practicing the above for a long time. All I have to do is figure the glide rate of your combined Rig (when off cruise, how long until throttle needed?). Roads you know, but I don’t. Etc.

When I do, it’s in the bag. And I will.

You understand this isn’t about me or you. It’s “listening” to what the truck tells us it wants. We work for the truck. The lowest fuel burn.

Let it drag a little on grades. Roll the downslope slower. Etc. Doesn’t change the trip. Sure as hell changes the fuel burn.

I figure out that roll, you’re toast.

THE TRIP PLAN is likeliest where you’d fail. Poor planning predicts piss-poor performance (greater fuel burn). This is what separates truck drivers. We have to stay two days ahead.

Have a great trip!

And post us a picture with a report afterwards: scale tickets; number of accel & decel events; engine hours against days miles; etc. The more you do as I’ve suggested (some is required) the more obvious it will be to you what you want to do next trip.


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Last edited by slowmover; 09-10-2019 at 06:08 AM..
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Old 09-10-2019, 06:00 AM   #28 (permalink)
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FWIW, I knew what I was doing when I chose both my pickup and my travel trailer. A lifetime of experience this design of RV.

In the South Central US and at the same speed where I don’t fall below 24-mpg solo, loaded (no matter weather or traffic), I can get my 17,000-lb, 63-foot long combined rig down the highway at an AVERAGE of 15-mpg. Which is lower than prediction. Should be at 17 (I have work to do).

I’ll bet you don’t know WHAT your Ferd is capable of. Steady-state 60-mph and never off cruise control. About 200 miles in a round trip to the same fuel pump. This test would have the same result no matter who’s driving. Is the point. Is how one tests changes.

The day you do this you’ll have the most important baseline number you can acquire for FE

Of course it doesn’t matter any comparison to mine. Plenty of differences exist between truck specification.

The competition is against ourselves.

Pulling a travel trailer SHOULD result in a 40% fuel burn penalty. Which could be improved. But any higher and we KNOW mechanical problems are waiting to be discovered.

AND we have our goal for city numbers. Which has no aero penalty.

SHOULD see almost the same MPG. If not, why not?

Which is my whole point in this post:

The Holy Ghost number

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Old 09-10-2019, 11:39 AM   #29 (permalink)
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So to clarify I did not mean to flat out say im better than most at driving but I drive more cautiously than the majority around me. I have an older brake controller than I have learned my way around for the various goosenecks, 5th wheels, and bumper pull trailers so I feel good enough about its abilities. Sure I could spend an extra $150 for a new controller and wire harness but nah.

As far as tongue weight, tire pressure, balance, all the good and bad about weight distribution of a pickup I have a decent understanding. But A 7.3l v8 will not reach the fuel economy of a straight 6 5.9 cummins without major changes. I barley got 19.5 with a tonneau cover on stock suspension about a 3in rake in the rear with 265/75r16 highway tires.

Now I run a level kit up front with 285/75r16 BFG AT2 tires. I raised my front end up just over 3inches to make the truck level, and added taller/wider/heavier tires. I can get close to 18 empty with the tonneau cover and easy highway driving now and that's really, really working my eco driving skills and only in summer. even with diesel kleen and winter fuel blend I am usually 2mpg less average. plus the snow/road conditions and sometimes needing 4x4 or little aired down tires etc.

Regarding towing. The side by side weighs 1720lbs empty with just gear/and fuel and the trailer weighs a hair under that. My truck on the cat scale with no passengers, just truck close to full tank as I can get and the gear is just under 8klbs. I'll never put the trailer on a scale to get the tongue weight totally perfect... its just not worth all the time. I have been eyeing the position on trailers for years without any negative effects. if I start driving and feel my brake test arnt good enough it takes 5 minutes to unstrap and move the unit a tad bit closer to the front etc. You can plan and plan and plan where to strategically place all the camping gear and food in a 5th wheel and still not be at the most effective pin weight. Im very conservative when towing. I try to almost never exceed the manufacture recommendations for weight limits, I have the over load top spring, front/rear sway bars, 3750 max rated tires very rarely ever needed above 70 of the max 80 psi, a very well maintained front suspension/rear suspension, brakes, steering, ball joints, drag link, track bar, bearings, blah blah. I get it im not an over the road trucker with 10 million miles towing rvs but generally speaking a little side by side and maybe 1500ish lb trailer behind 8k is going to be fine. I check tire pressure, grease bearings, adjust brakes, keep good distance (seems relative to each person these days) and I just plain take care of my equipment. I can only drive as good as I can and hope I can react quick enough to react to my mistake or someone else's.


to get back on the point. Im out of state working for the week but soon as I get pictures. looking for feed back on the trailer set up if any mods would be affordable/worth it on the trailer unit.
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Old 09-10-2019, 12:06 PM   #30 (permalink)
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