Posted 2011-04-21 8:48 PM (#133314) Subject: Question about "Vented tailgate" on P/U trucks.
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Location: Sumas Washington
After the first towing of my new G/N LQ trailer I noticed the rubber bed mat lifting and blowing up at speed. A friend is sold on his louvered tailgate on his Dodge truck. Is there any real benefits to these vented gates. Anyone have any real world stories to tell??
Posted 2011-04-21 10:17 PM (#133316 - in reply to #133314) Subject: RE: Question about "Vented tailgate" on P/U trucks.
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Location: western PA
There is a low pressure area behind the cab, caused by the airflow flowing around and over the body work. As the airflow meets behind the cab, it starts a buffeting just in front of the tailgate. The tailgate blocks its rearward path, induces some drag and causes a slight loss of fuel mileage. The tailgate also induces its own low pressure area behind the rear bumper, and causes additional drag.
A louvered tailgate is supposed to allow the airflow to continue with less abatement, and reduce the amount of disturbance caused by the blockage. Web gate replacements, or removing the tailgate also mitigates the airflow problems.
Posted 2011-04-21 10:39 PM (#133318 - in reply to #133314) Subject: RE: Question about "Vented tailgate" on P/U trucks.
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Location: Decatur, Texas
Originally written by gonzo1066 on 2011-04-21 8:48 PM
After the first towing of my new G/N LQ trailer I noticed the rubber bed mat lifting and blowing up at speed. A friend is sold on his louvered tailgate on his Dodge truck. Is there any real benefits to these vented gates. Anyone have any real world stories to tell??
No real benefits at all in my opinion. Before I bought our last truck, we always had trucks with tailgates and I was always doing different things trying to get the best fuel mileage while unloaded and the difference between having the tailgate vs. no gate or vented gate is with in 10ths...
Something to think about is even if you have a vented tailgate or no tailgate you will still have bedmat problems when towing a gooseneck! The trailer is going to act just like the tailgate at hwy speeds!.....
If the bed mat is your worry, I would rather spend the hard earned money on a spray in bedliner and use the mat to stand your horses on when you wash them.
Posted 2011-04-21 10:50 PM (#133319 - in reply to #133314) Subject: RE: Question about "Vented tailgate" on P/U trucks.
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Location: North Carolina
Real world... Small effects on aerodynamics. But if given a choice, keep the tailgate up. The tailgate provides substantial structural support to the truck body.
"...The aerodynamic effects of the pickup truck tailgate are examined in this paper. It is shown that the removal or the lowering of the tailgate increases the aerodynamic drag of a pickup truck, increases lift by up to sixty percent and increases the yawing moment. All these changes are negative and reduce vehicle performance, albeit, only by small amounts. This finding demonstrates that the commonly seen removal of tailgates to reduce aerodynamic drag is a public misconception that should be discouraged by manufacturers and by regulators..."
Posted 2011-04-21 11:26 PM (#133325 - in reply to #133324) Subject: RE: Question about "Vented tailgate" on P/U trucks.
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Originally written by gonzo1066 on 2011-04-21 8:13 PM
I have never contemplated removing the tailgate with the empty truck, However when towing the GN trailer I could imagine some benifits. MAYBE??
I think NOT. A closed tailgate adds structural support to the bed. Try twisting an open box versus a closed box. The bed is attached to the frame. So a closed box (tailgate closed) adds to the frame rigidity and strength. Besides, stuff one leaves in the truck bed falls out if you remove the tailgate. My buddy found this out the expensive way
Posted 2011-04-21 11:29 PM (#133326 - in reply to #133324) Subject: RE: Question about "Vented tailgate" on P/U trucks.
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Originally written by gonzo1066 on 2011-04-21 12:13 AM
I have never contemplated removing the tailgate with the empty truck, However when towing the GN trailer I could imagine some benifits. MAYBE??
The best one is after you uncouple the goose hitch, get in and drive off, you then feel a thump, hear a crash and realise your tailgate is still up. The worse part is trying to explain to your wife, how it was she, who had to have left the gate up. The LQ then becomes your next living space. It beats the dog house.
I agree with the experts, HOWEVER they do NOT address towing a GN or 5th wheel trailer and the impact of areodynamics with a closed gate vs a open one.
Posted 2011-04-22 5:40 AM (#133330 - in reply to #133326) Subject: RE: Question about "Vented tailgate" on P/U trucks.
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Originally written by gard on 2011-04-21 12:29 AM
Originally written by gonzo1066 on 2011-04-21 12:13 AM
I have never contemplated removing the tailgate with the empty truck, However when towing the GN trailer I could imagine some benifits. MAYBE??
The best one is after you uncouple the goose hitch, get in and drive off, you then feel a thump, hear a crash and realise your tailgate is still up. The worse part is trying to explain to your wife, how it was she, who had to have left the gate up. The LQ then becomes your next living space. It beats the dog house.
Ha Ha Ha!....Sorry, I just had a visual! Truely, it isn't funny.....
Posted 2011-04-22 6:01 AM (#133331 - in reply to #133314) Subject: RE: Question about "Vented tailgate" on P/U trucks.
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I've been pulling gooseneck trailers since 1997 and almost NEVER leave my tailgate on. If I put anything into the bed while I am towing, which is rare, I put a net across the back. I have never had a problem with the truck flexing or not being stable due to the lack of tailgate.
My question would be why would manufacturers make tailgates removeable if taking them off gravely effected the structural integrity of a truck??? Sounds like they would be really opening themselves up to multiple lawsuits due to the accidents caused by lack of tailgates on trucks. I know I see this listed as the cause of accidents all the time- NOT!!!
Posted 2011-04-22 6:31 AM (#133332 - in reply to #133314) Subject: RE: Question about "Vented tailgate" on P/U trucks.
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For several years and two trucks, we hauled with BP trailers and used truck campers. During the Spring, Summer and early Fall months, the tailgates were removed and not reinstalled until the riding season ended. While the gates were off, we never experienced any difference in the stability or flexibility of the frames. The trucks routinely carried whatever fit in the bed, with the same amount of load capacity and driving capabilities.
Posted 2011-04-22 8:20 AM (#133335 - in reply to #133314) Subject: RE: Question about "Vented tailgate" on P/U trucks.
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Location: Northern Utah
I learned a lesson one day years ago. My tail gate was off and Loaded the truck and GN. Put 3-4 bales of hay in the bed of the truck and headed out.
Going down the freeway, I feel a bump and look in the mirror and see a green cloud behind the trailer. A 70lb bale of hay had blown out and gone under the trailer. When it hit the axles it had come apart. It created a serious cloud that made it almost impossible for other drivers to see through.
Lesson learned. Don't drive without some kind of gate. Even fairly heavy items like full bales of hay will blow out.
Posted 2011-04-22 9:10 AM (#133338 - in reply to #133314) Subject: RE: Question about "Vented tailgate" on P/U trucks.
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Location: Texas
Here's my take on the louvered tailgates: I think the main selling point is not having to open or close it while hooking/unhooking the trailer.
I'm not sure that the tailgate adds much appreciable rigidity to the frame. But, there is no doubt that a closed tailgate contributes to the rigidity of the box. That is a simple statics problem. Look at how the box sides are welded to the box floor. It's just not that rigid. Take two pickups, take the tailgate off one, and drive them 100,000 miles down washboarded gravel roads, and you'll plainly see the benefits of the rigidity of the tailgate.
Posted 2011-04-22 9:36 AM (#133340 - in reply to #133314) Subject: RE: Question about "Vented tailgate" on P/U trucks.
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I had the very same experince as Painted Horse. As luck would have it, I had a unmarked police car behind me when the bale came out and went under the trailer. He stopped me, and politely told me what happened, and he suggested that I secure my load. Never got a ticket, but I learned to tie down bales well if hauling them under the neck of gooseneck trailer w/o a tailgate on th truck.
Posted 2011-04-22 1:25 PM (#133344 - in reply to #133314) Subject: RE: Question about "Vented tailgate" on P/U trucks.
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Location: Minnesota
Had a good friend whose daughter was on her way to a rodeo in a truck with no tailgate pulling his brand new LQ trailer. Spare tire for the truck was loose in truck box. She saw it get lifted, fly out and under the trailer. BUMP! She got to the rodeo and was going to use the bathroom, floor of shower was pushed up almost a foot and toilet was laying on it's side. Spare had pushed the tanks up. $9,000.00 later it was fixed. Both he and I had been driving without the tailgates for years. Not any more. Always on and up and latched.
Mythbusters proved the fuel mileage thing about keeping your tailgate up too.
Posted 2011-04-22 10:39 PM (#133359 - in reply to #133314) Subject: RE: Question about "Vented tailgate" on P/U trucks.
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You asked if anyone had any real life stories,I do.We were planning on taking a friend to ride with us the next day,and,our 4Star was going.We keep it at a tractor shed on my farm about 5 mi from where we live.It was late,we were tired.The 4Star had been backed in at an angle,and,I was backing up my husband's dooley under the GN.He hitched it up,and,when I moved off a little,found that the dropped tailgate was stuck against the 4Star's spare tire. it wouldn't go back up.D id we unhitch the trailer? H no,we weren't that smart.He called to me "pull off and straighten up a little." I felt it lugging a little,but,it moved off,all right.Something had to give,and,it was the dropped tailgate.If you ever warp one as we did,you'll find that they are expensive as all get-out to replace stock and nearly impossible to ever straighten.So,he opted for a louvered tailgate this time.I tell this at great risk for multiple laughs that I won't even know about,hopefully.Hey,it's been done by some of you,too.
Posted 2011-04-22 11:23 PM (#133361 - in reply to #133338) Subject: RE: Question about "Vented tailgate" on P/U trucks.
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Originally written by jdzaharia on 2011-04-22 9:10 AM
Here's my take on the louvered tailgates: I think the main selling point is not having to open or close it while hooking/unhooking the trailer.
I have never seen a vented gate that was low enough in the center to hook up a gooseneck without having to let it down. 5th wheel hitch will clear, but a gooseneck?
Posted 2011-04-22 11:36 PM (#133362 - in reply to #133329) Subject: RE: Question about "Vented tailgate" on P/U trucks.
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Location: Decatur, Texas
Originally written by gonzo1066 on 2011-04-22 12:24 AM
HOWEVER they do NOT address towing a GN or 5th wheel trailer and the impact of areodynamics with a closed gate vs a open one.
They did not, but I did in my post! Your "areodynamics" will be NO different while towing a 5th wheel or gooseneck with or without the tailgate! The wind or air coming around and over the cab of the truck is going to hit the lower front of the trailer any way! Test it for yourself, get some sort of paper, floor mat or something and hang it under the gooseneck above the jack so you can see it. Then drive around with the tailgate on and off and watch the movement of whatever you hung up and you will see there is not going to be any "areodynamics" difference between them....
Most goosenecks and 5th wheels are like pulling a barn door around with you any way.......
Posted 2011-04-23 10:57 AM (#133375 - in reply to #133361) Subject: RE: Question about "Vented tailgate" on P/U trucks.
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Originally written by hogtownboss on 2011-04-22 11:23 PM
I have never seen a vented gate that was low enough in the center to hook up a gooseneck without having to let it down. 5th wheel hitch will clear, but a gooseneck?
I agree. I think they're marketed toward the 5th wheel crowd.
Sorry, I don't have much input on the original question, except that I've seen bed mats flapping in the wind with original tailgates and no tailgate, alike.
Posted 2011-04-23 3:54 PM (#133382 - in reply to #133314) Subject: RE: Question about "Vented tailgate" on P/U trucks.
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I have that same gate on a 2001 Dodge Ram 2500 that I am driving right now and I still have to either let the gate down or raise the trailer another 3 inches to clear the gate when hooking up and unhooking. Which would be ok for someone who uses the same truck every single time.
Posted 2011-04-23 8:36 PM (#133387 - in reply to #133314) Subject: RE: Question about "Vented tailgate" on P/U trucks.
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Location: Sumas Washington
So from reading this thread, I assume that quite a few folks assume that hauling something in the bed of a truck un tied down is ok without a tailgate?? I also assume that a few people have had things BLOW OUT OF THE BED when the GN is hitched up although they did not have that problem when the trailer was not being towed.
A simple deduction on my part would be that turbulence caused by the trailer is blowing heavy objects out of the bed of the truck.. Is this not a high pressure area caused by air flow off of the front of the trailer? Does the air coming over the cab of the truck deflect down and intensify due to the spillage of air from the relitivly flat nose of the trialer??
I have had my aluminum trailer leveling ramps (about 20# each) nearly blow over the tailgate when the trailer is being towed. Is this not a indication of high pressure and high wind speed? When the trailer is not behind the truck the ramps will ride in the same spot at well over 90 miles per hour.
Posted 2011-04-23 10:22 PM (#133390 - in reply to #133314) Subject: RE: Question about "Vented tailgate" on P/U trucks.
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When the air flows around the truck and trailers' body work, it creates a LOW pressure (IE vacuum) in the bed and underneath the goose area. That is why things are lifted out of the bed, or lifted enough that they can then slide to the rear. The "bubble" the experts spoke about, is a result of the trapped air being drawn into the bed.
Bernouli's principle is also the reason a million pound machine can fly.