Questions about how to properly distribute weight... Air bags? WDH?
05-16-2016, 11:49 PM
#1
Questions about how to properly distribute weight... Air bags? WDH?
So I feel dumb asking these questions as I should probably know better. But here goes...
I have a 2012 FX4 Supercrew. I tow a 28' travel trailer that allegedly weighs about 5000 lbs dry. It came with a weight distribution hitch which I have always used. Last weekend the 4 hour drive was a little more white-knuckled than I would prefer. The trailer was giving me all kinds of sway issues and was unpredictable over 65 MPH. Once I got to my destination, I realized that I needed more tongue weight. The only other time this happened was when I had the bikes on the trailer's bumper mounted rack. I figured the easiest way to fix this was to move the bikes inside the trailer and to the front. I also left the freshwater tank partially full as it is in front of the trailer axles. I am really not a fan of either of these options, but I also didn't appreciate the stressful drive up north. On the way home, the system drove pretty well. I was able to motor along at 75 with little to no issues. Before I go on, I will point out that my goal is not speed, but to get a smoother and SAFER ride for the family.
I have begun putting more thought into weight distribution and possibly adding the Firestone airbags. But I wonder if what I am going to do will just keep taking more weight off the tongue. So I ask the following questions, which I imagine sound silly to those of you who tow a lot:
1) Is it possible to take TOO MUCH weight off the tongue with the weight distribution hitch? I initially figured that if using the 4th link on the chain, trying to get to the 5th or 6th link was better. But if I really crank down on the WDH, am I just sending that weight back off of the tongue to the back of the trailer? Or is it keeping the weight on the tongue but sending some of it to the front axle?
2) If I add the Firestone air bags am I just creating the same problem? In the future, I plan on loading the trailer more tongue heavy in order to reduce sway. As I add more weight, I would prefer to keep the ride of the truck smoother and level. So I was thinking of adding the Firestone f2525 ride right bags. But if I use these and level the back of the truck, is that going to reduce the tongue weight by sitting the trailer back?
3) Am I right to assume that I want the trailer AND the truck to sit as close to level as possible? I am hoping that by correctly using the WDH and/or the air bags, I can keep the whole rig level, but also add more hitch weight. Is this even possible, or am I really just adding hitch weight and then sending it back to the trailer by leveling things out?
Thanks for any insight!
I have a 2012 FX4 Supercrew. I tow a 28' travel trailer that allegedly weighs about 5000 lbs dry. It came with a weight distribution hitch which I have always used. Last weekend the 4 hour drive was a little more white-knuckled than I would prefer. The trailer was giving me all kinds of sway issues and was unpredictable over 65 MPH. Once I got to my destination, I realized that I needed more tongue weight. The only other time this happened was when I had the bikes on the trailer's bumper mounted rack. I figured the easiest way to fix this was to move the bikes inside the trailer and to the front. I also left the freshwater tank partially full as it is in front of the trailer axles. I am really not a fan of either of these options, but I also didn't appreciate the stressful drive up north. On the way home, the system drove pretty well. I was able to motor along at 75 with little to no issues. Before I go on, I will point out that my goal is not speed, but to get a smoother and SAFER ride for the family.
I have begun putting more thought into weight distribution and possibly adding the Firestone airbags. But I wonder if what I am going to do will just keep taking more weight off the tongue. So I ask the following questions, which I imagine sound silly to those of you who tow a lot:
1) Is it possible to take TOO MUCH weight off the tongue with the weight distribution hitch? I initially figured that if using the 4th link on the chain, trying to get to the 5th or 6th link was better. But if I really crank down on the WDH, am I just sending that weight back off of the tongue to the back of the trailer? Or is it keeping the weight on the tongue but sending some of it to the front axle?
2) If I add the Firestone air bags am I just creating the same problem? In the future, I plan on loading the trailer more tongue heavy in order to reduce sway. As I add more weight, I would prefer to keep the ride of the truck smoother and level. So I was thinking of adding the Firestone f2525 ride right bags. But if I use these and level the back of the truck, is that going to reduce the tongue weight by sitting the trailer back?
3) Am I right to assume that I want the trailer AND the truck to sit as close to level as possible? I am hoping that by correctly using the WDH and/or the air bags, I can keep the whole rig level, but also add more hitch weight. Is this even possible, or am I really just adding hitch weight and then sending it back to the trailer by leveling things out?
Thanks for any insight!
05-17-2016, 12:08 AM
#2
Senior Member
Picture of the set up could be useful. If adding airbags air them up first before setting the WDH. If you are getting to chain links 4,5 and 6 I am wondering if the WDH is not angled correctly or ball height is off..................the bars should be level. Yes you want the trailer level or SLIGHTLY nose down. Start the set up with the trailer level and the hitch ball an inch taller.
05-17-2016, 12:11 AM
#3
Picture of the set up could be useful. If adding airbags air them up first before setting the WDH. If you are getting to chain links 4,5 and 6 I am wondering if the WDH is not angled correctly or ball height is off..................the bars should be level. Yes you want the trailer level or SLIGHTLY nose down. Start the set up with the trailer level and the hitch ball an inch taller.
But my question remains: If I take up a lot of weight with the WDH, is that removing hitch weight and putting it back onto the trailer axles? Or is it distributing it onto the front axle of the truck?
05-17-2016, 09:10 AM
#4
Senior Member
Sounds like you need to go through the setup process from scratch.
To answer your question, yes the WDH transfers some weight to the TV front axle and some to the TT axle but it is not a lot.
To answer your question, yes the WDH transfers some weight to the TV front axle and some to the TT axle but it is not a lot.
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Ricktwuhk (05-17-2016)
05-17-2016, 09:29 AM
#6
True North Strong & Free
Here is my take, I have a similar weighed TT. When I bought our TT I also bought/invested in a WDH with sway control, that was in 08. We have over 45k kms of travel on that TT, incl trips to OR x2, ID, MT, CO, WY, ND & SD, some repeat places, not to mention Western Canada and local CG. Ive never had to reset my hitch or adjust it other than the pull height d/t different truck. Ive pulled through brutal winds of nature and man made w/o incident.
If you're going to invest in 10s of thousands of $$ in a trailer, spend the few extra $s and invest in a good WDS that has built in sway control, you'll never regret it....
If you're going to invest in 10s of thousands of $$ in a trailer, spend the few extra $s and invest in a good WDS that has built in sway control, you'll never regret it....
Last edited by Norotso; 05-17-2016 at 09:38 AM.
05-17-2016, 09:30 AM
#7
Grumpy Old Man
First, you must know your tongue weight. Best and most accurate way is to use a Sherline tongue weight scale.
https://www.etrailer.com/Tools/Sherline/5780.html
If you don't want to invest in a TW scale, then you can determine TW by weighing the rig twice, once with the trailer but without the spring bars tightened, and again without the trailer. Add the weights on the front and rear axles of the TV to get GVW (gross vehicle weight). Subtract the GVW without the trailer from the GVW with the trailer but without the spring bars attached. The answer is your TW.
Next, you must have a WD hitch that is designed with tongue weight (TW) to match your trailer' wet and loaded TW.
If you are able to distribute more than 50% of gross wet and loaded TW off the rear axle of the TV, then the spring bars of your WD hitch are too heavy duty for that trailer, or maybe you just tightened the spring bars too tight.
Using a tongue weight scale to determine TW, weigh the rig twice. Once with the spring bars disconnected, and again with the spring bars tightened to where you think they should be. Calculate the percentage of TW difference for each axle of the rig. Ideal is 20% to 25% of gross wet and loaded tongue weight distributed back to the trailer axles, and another 20% to 25% distributed to the front axle of the TV. That leaves 50% to 60% of gross wet and loaded tongue weight on the rear axle.
First calculate the TW remaining on the rear axle. The tighter the spring bars, the less weight will remain on the rear axle. More than 60% TW on the rear axle of the TV says your spring bars are not tight enough. Less than 50% says the spring bars are too tight.
After you have 50% to 60% of gross wet and loaded TW remaining on the rear axle of the TV, the next step is to check the weight distributed to the front and trailer axles. Goal is 20% to 25% distributed to both the front and trailer axles. If you have more or less than the goal, then the fix is to change the angle of the hitch head to the tongue of the trailer.
The primary purpose of air bags in the rear suspension is to hide the symptoms of being overloaded. If you headlights aim at the stars at night, then you're overloaded and need air bags to bring the headlights back down to earth. "Overloaded" is defined as exceeding the GVWR of your tow vehicle. If the rear end of your TV sags when the trailer is tied on with the spring bars of the WD hitch tightened, then you're probably overloaded.
https://www.etrailer.com/Tools/Sherline/5780.html
If you don't want to invest in a TW scale, then you can determine TW by weighing the rig twice, once with the trailer but without the spring bars tightened, and again without the trailer. Add the weights on the front and rear axles of the TV to get GVW (gross vehicle weight). Subtract the GVW without the trailer from the GVW with the trailer but without the spring bars attached. The answer is your TW.
Next, you must have a WD hitch that is designed with tongue weight (TW) to match your trailer' wet and loaded TW.
If you are able to distribute more than 50% of gross wet and loaded TW off the rear axle of the TV, then the spring bars of your WD hitch are too heavy duty for that trailer, or maybe you just tightened the spring bars too tight.
Using a tongue weight scale to determine TW, weigh the rig twice. Once with the spring bars disconnected, and again with the spring bars tightened to where you think they should be. Calculate the percentage of TW difference for each axle of the rig. Ideal is 20% to 25% of gross wet and loaded tongue weight distributed back to the trailer axles, and another 20% to 25% distributed to the front axle of the TV. That leaves 50% to 60% of gross wet and loaded tongue weight on the rear axle.
First calculate the TW remaining on the rear axle. The tighter the spring bars, the less weight will remain on the rear axle. More than 60% TW on the rear axle of the TV says your spring bars are not tight enough. Less than 50% says the spring bars are too tight.
After you have 50% to 60% of gross wet and loaded TW remaining on the rear axle of the TV, the next step is to check the weight distributed to the front and trailer axles. Goal is 20% to 25% distributed to both the front and trailer axles. If you have more or less than the goal, then the fix is to change the angle of the hitch head to the tongue of the trailer.
The primary purpose of air bags in the rear suspension is to hide the symptoms of being overloaded. If you headlights aim at the stars at night, then you're overloaded and need air bags to bring the headlights back down to earth. "Overloaded" is defined as exceeding the GVWR of your tow vehicle. If the rear end of your TV sags when the trailer is tied on with the spring bars of the WD hitch tightened, then you're probably overloaded.
Last edited by smokeywren; 05-17-2016 at 09:33 PM.
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05-17-2016, 02:47 PM
#8
Senior Member
sorry but airbags do more than help an "overloaded" situation.
they will stop any bounce or porpoising between the truck and trailer when going over any less than smooth roads. they will add stability to any truck that does towing duties.
even a properly set up WD system can benefit from a set of airbags.
they will stop any bounce or porpoising between the truck and trailer when going over any less than smooth roads. they will add stability to any truck that does towing duties.
even a properly set up WD system can benefit from a set of airbags.
05-17-2016, 07:16 PM
#9
Senior Member
I have a Equalizer weight distributing hitch for my trailer with 590lb dry tw. The rear doesn't sag at all but on bumpy roads the trailer bounces the rear of the truck. I installed firestone air bags to eliminate this problem so I would say they are useful for more than just an overloaded truck.
05-17-2016, 08:32 PM
#10
Senior Member
Has the OP ever considered taking the rig to the scales to determine the weight distribution situation?
The scale numbers take the guesswork out of it. The truck stops are usually busy places, but you can pull off the scales into the parking lot and make adjustments right there. Then go reweigh and keep at it until you get it right.
It's usually about $12 for the first weigh and then only $2 for each reweigh.
Three weighs gives the picture. One full rig with WDH bars attached, one full rig with WDH bars loose, one truck only. They you can tell what you have and what you need to adjust.
http://www.publicscaleslocator.com
The scale numbers take the guesswork out of it. The truck stops are usually busy places, but you can pull off the scales into the parking lot and make adjustments right there. Then go reweigh and keep at it until you get it right.
It's usually about $12 for the first weigh and then only $2 for each reweigh.
Three weighs gives the picture. One full rig with WDH bars attached, one full rig with WDH bars loose, one truck only. They you can tell what you have and what you need to adjust.
http://www.publicscaleslocator.com