Print Page | Close Window

Should I adjust my towing setup?

Printed From: R-pod Owners Forum
Category: R-pod Discussion Forums
Forum Name: Podmods, Maintenance, Tips and Tricks
Forum Discription: Ask maintenance questions, share your podmods (modifications) and helpful tips
URL: http://www.rpod-owners.com/forum_posts.asp?TID=12035
Printed Date: 30 Apr 2024 at 3:46am
Software Version: Web Wiz Forums 9.64 - http://www.webwizforums.com


Topic: Should I adjust my towing setup?
Posted By: clickscrazy
Subject: Should I adjust my towing setup?
Date Posted: 12 Aug 2018 at 4:50pm
Just finished a trip to St. George Island, FL with our 2018 171, towed by our 2014 TDI Touareg. The TV is a new setup, with only 1 other short trip clocked.

From the ground, the 171 sits 19.5" i the front, and 19" in the rear, so when towing it is pretty level.

However, I noticed sway I had not experienced before cruising at 60 to 65 max on the highway with trucks and even vehicles passing me. I did not have my sway control on, as in the last several FL trips, I didn't seam to need it.

I was wondering if my sway was caused by the conditions I just never experienced before or if maybe I should bring my ball down a bit to give the front more of a dip.

Thoughts?

Note: I was also running WDH, which was not very tight, just to help with dips and stuff.


-------------
2018 R-Pod 171
2014 VW Touareg TDI



Replies:
Posted By: mcarter
Date Posted: 12 Aug 2018 at 5:28pm
Personally I would not lower hitch. You have a level rig. Does your WDH not have sway control? How much sway? Anything happen to increase rear weight?

-------------
Mike Carter
2015 178
" I had the right to remain silent, I just didn't have the ability."


Posted By: GlueGuy
Date Posted: 12 Aug 2018 at 6:08pm
Front/rear weight distribution will have more effect on sway than that small amount of out-of-level. I would guess that when you were experiencing sway you may have inadvertently loaded more aft than you have in the past? That's a SWAG.  

-------------
bp
2017 R-Pod 179 Hood River
2015 Ford F150 SuperCrew 4WD 3.5L Ecoboost


Posted By: Ben Herman
Date Posted: 12 Aug 2018 at 6:13pm
Since you have sway control I'd try it with that next time and see if you notice a difference. Not sure what your former TV was but the Touareg has a pretty sort wheel base which could make a difference.


Posted By: clickscrazy
Date Posted: 12 Aug 2018 at 6:47pm
Previous TV was a trailblazer, which actually had a shorter wheelbase.

I do have sway control. Will try that for sure and maybe load more to the front.

-------------
2018 R-Pod 171
2014 VW Touareg TDI


Posted By: jato
Date Posted: 12 Aug 2018 at 8:52pm
We encountered this problem on our '08 Explorer when we first purchased our 177.  Originally we had a 2" drop on the hitch, pod was nearly level, and we experienced a lot of sway.  We then went with a 4" drop hitch and the sway was eliminated.  Both cases we were using a sway bar link.  For the most part the sway was minimal using the 2" drop, but it could be felt while driving.  With the 4" drop, that feel of sway never materialized while driving.

-------------
God's pod
'11 model 177
'17 Ford F-150 4WD 3.5 Ecoboost
Jim and Diane by beautiful Torch Lake
"...and you will know the Truth and the Truth will set you free."


Posted By: OldNeumanntapr
Date Posted: 12 Aug 2018 at 9:25pm
I wouldn't tow any faster than 60 mph, but that's just me.


Posted By: clickscrazy
Date Posted: 12 Aug 2018 at 9:36pm
Ok. I may try dropping it a bit. I don't drive faster than 65, but even at 60 it was felt.

-------------
2018 R-Pod 171
2014 VW Touareg TDI


Posted By: clickscrazy
Date Posted: 12 Aug 2018 at 9:38pm
I did also go one more link up on my wdh this time. That could also perhaps have caused the problem.

-------------
2018 R-Pod 171
2014 VW Touareg TDI


Posted By: GlueGuy
Date Posted: 13 Aug 2018 at 2:40pm
Double nickel is the limit for vehicles with trailers in California. We've gotten used to going slow and easy, and enjoying the trip.

-------------
bp
2017 R-Pod 179 Hood River
2015 Ford F150 SuperCrew 4WD 3.5L Ecoboost


Posted By: mcarter
Date Posted: 13 Aug 2018 at 3:21pm
Jato,

As I recall you don't use a WDH. So a hitch drop could help, with the WDH the OP has , they should be able to compensate for sway if properly adjusted.

-------------
Mike Carter
2015 178
" I had the right to remain silent, I just didn't have the ability."


Posted By: john in idaho
Date Posted: 13 Aug 2018 at 6:52pm
I got rid of the last little bit of side to side movement in the mirror by changing out the Load range C tires with 50 lbs of air for load range E with 80 lbs of air pressure.  I have found that my Ram PU likes to pull at 62 mph in tow-haul mode. And I hardly ever have to pass anyone.   But we have real mountains to contend with.


Posted By: OldNeumanntapr
Date Posted: 13 Aug 2018 at 7:24pm
Originally posted by GlueGuy

Double nickel is the limit for vehicles with trailers in California. We've gotten used to going slow and easy, and enjoying the trip.



I too live in CA and I’ve been passed by people pulling trailers that were doing at least 75. I’ve NEVER seen a CHP pull over a truck and trailer for speeding.


Posted By: jato
Date Posted: 13 Aug 2018 at 9:25pm
Good memory Mike, you are correct as I have never used a WDH and you are again correct in saying the OP, by properly adjusting his WDH, he should be able to safely compensate for sway.

-------------
God's pod
'11 model 177
'17 Ford F-150 4WD 3.5 Ecoboost
Jim and Diane by beautiful Torch Lake
"...and you will know the Truth and the Truth will set you free."


Posted By: clickscrazy
Date Posted: 14 Aug 2018 at 7:37am
So I think my plan will be this. Drop my WDH ring down one back to where it was (So it is not as tight) and run my Sway Control this time. Also, if I can, move a few more items up front I will.

We will see how that goes before dropping the ball.  

I run 60lbs in my tires. I have the 2018 with 15" wheels.


-------------
2018 R-Pod 171
2014 VW Touareg TDI


Posted By: mcarter
Date Posted: 14 Aug 2018 at 7:57am
Good plan, you'll get it right, takes some adjusting.

-------------
Mike Carter
2015 178
" I had the right to remain silent, I just didn't have the ability."


Posted By: offgrid
Date Posted: 28 Aug 2018 at 5:41pm
Sorry for the slow response, I've been off boondocking/off grid camping the past couple of weeks. 

One issue with wd hitches is that they reduce the load on the rear axle of the TV by moving it to the front axle and to the trailer axle. To the extent that our rPod axles are, shall we say to be polite, not over-engineered for the application, you may want to either forego use of or or minimize the tension on your wd hitch springs to help reduce the rear axle load. This assumes your TV is robust enough to handle it. 

Many of us however, myself included, chose an rPod so we could tow it with a midsize SUV. Then if we are boondocking we load them up with water, dual batteries, dual propane, solar etc.  This requires use of a wd hitch and creates the need to find a balance point between hitch tension and trailer axle load. What you don't want to do is crank on your wd hitch until the TV "looks level" without first doing the math to know what that is doing to your trailer axle.

Here is a link to a nice calculator. The only missing item in it I could see was accounting for the wd hitch itself, they're not light. Add the hitch to the weight of your TV and you should be good to go. 

https://www.ajdesigner.com/apptrailertow/weightdistributionhitch.php

In my case, I have a wd hitch rated for 1200 lbs, and if I crank that much tension on its springs my Highlander does indeed level out and looks nice, but I have added 230 lbs to my trailer axle load in the process.  Not good.

I also highly recommend taking your rig fully loaded with everything and everyone for camping to a public scale and weighing all three axles, then two, then one. If you do that, with and without the wd hitch under tension you can directly see the effects. Also if you then drop your trailer and weigh your TV separately you can obtain your tongue weight without a special scale or the "bathroom scale procedure". 

You will then have all the data you need to run the math and know if you have all your axles as well as your GCVW within limits and by how much. I used the free scale at my local waste transfer station for this and asking politely, but do try to go during a quiet time so you're not holding folks up.  

In my case I was at about 3350 on the trailer axle with full tension on the wd hitch. By backing off to about 700 lbs tension on the hitch I dropped to 3250 on the axle while still having large reserves on both front and rear TV axles. However, as I still have some more mods (weight) to add to the rPod, I think an axle upgrade is probably in my future.  


-------------
1994 Chinook Concourse
1995 RV6A Experimental Aircraft
2015 Rpod 179 - sold


Posted By: offgrid
Date Posted: 01 Sep 2018 at 6:22am
I was curious so I spent a bit more time on the question of what else besides the trailer axle can be overstressed by excessive weight distribution hitch tension. Turns out there are a couple of additional problem areas. 

First are the trailer frame rails. Consider that the trailer structure is basically two single ended cantilever beams supported at one end by the hitch and by the trailer axle inboard from the other end. The loading on these beams is more or less uniform along their length without the wd hitch load. By tensioning the wd hitch I am adding a point load 2.5 ft in from the hitch end. This load combination creates a max bending stress on the rails somewhere near where the tongue is welded to the main frame rails under the front of the trailer box. On my 179 at 1200 lbs tension on the wd hitch and a fully loaded trailer I am increasing the max bending stress on the frame rails by about 80% at that point. 

So, is this additional frame loading a problem or not? I'm not a vehicle design engineer and am not interested in picking up any liability for taking a position on that.  I will only say that taking a quick look on line at the g load factors typically used in vehicle frame design and checking the section properties of the rPod frame rails (which on my 179 are 0.1 in thick 4x2 box tubes) I wouldn't want to drive around very much with 1200 lbs tension on my hitch. 

Second is the receiver hitch. Think of the wd hitch as the equivalent of a really strong guy shoving a big breaker bar into the receiver and rotating it to push the front wheels down into the pavement. There is a giant moment (torque) being applied at the receiver (3000 ft-lbs on my hitch at 1200 lbs tension). What could possibly go wrong? If you don't have a hitch rated for wd use here's what can happen. And no, that's not my Highlander. So, be sure your hitch (and its attachment to your TV) is rated for wd use. This one wasn't. 





-------------
1994 Chinook Concourse
1995 RV6A Experimental Aircraft
2015 Rpod 179 - sold


Posted By: GlueGuy
Date Posted: 01 Sep 2018 at 9:37am
Originally posted by offgrid

First are the trailer frame rails. Consider that the trailer structure is basically two single ended cantilever beams supported at one end by the hitch and by the trailer axle inboard from the other end. The loading on these beams is more or less uniform along their length without the wd hitch load. By tensioning the wd hitch I am adding a point load 2.5 ft in from the hitch end. This load combination creates a max bending stress on the rails somewhere near where the tongue is welded to the main frame rails under the front of the trailer box. On my 179 at 1200 lbs tension on the wd hitch and a fully loaded trailer I am increasing the max bending stress on the frame rails by about 80% at that point.
I believe that the tension can not be that high. To begin with, the tongue weight on a fully loaded RP-179 is going to be in the neighborhood of 500 lbs. That means the maximum weight you can distribute is 500 lbs. Some portion of that tongue weight gets transferred to the front wheels. The amount is determined by the length of the moment arm, which is driven by the distance between the WDH and the rear wheels of the TV. Conversely, some of that tongue weight is transferred back to the trailer wheels. Because the moment arm is much longer, the amount of weight transferred back to the trailer wheels will be much smaller.


-------------
bp
2017 R-Pod 179 Hood River
2015 Ford F150 SuperCrew 4WD 3.5L Ecoboost


Posted By: BVK
Date Posted: 01 Sep 2018 at 10:09am
Originally posted by GlueGuy

Double nickel is the limit for vehicles with trailers in California. We've gotten used to going slow and easy, and enjoying the trip.
Oh, I like that rule.

In parts of Washington, slow turn-outs are enforced for vehicles with 5+ vehicles behind them. With people driving as if the 5mph-over rule is real, it can prove for some stressful times. I just remind myself that, if I'm going the speed limit, I'm not a slow vehicle.


-------------
2012 RP-171 HRE, 2006 F-150


Posted By: lostagain
Date Posted: 01 Sep 2018 at 10:18am
Offgrid raises some very valid concerns about the design and use of trailers, hitches, and receivers.  Presumably the designers of the trailers, receivers, and WHD hitches take these important stresses into account.  If not, they run the risk receiving an invitation to justify their design calculations in the presence of a jury in a product liability case.  

All of these forces are foreseeable for the designers of each component and each component designer must anticipate the use of the other's product.  Thus, they have to take the twisting and bending loads into account and adequately design for them and/or advise the users of the load limits and dangers.  In most states, product liability rules require designers to factor in not only foreseeable uses but also misuses that pose a risk of injury.  In other words, if a receiver, such as the one in the pictured Toyota Highlander that appears to have been damaged by torsional loading of a WDH, is not capable of sustaining such loads, Toyota has the duty to warn of the load limits or advise against the use of a WDH.

For example, I bought our Pod from a dealer who sold us both the trailer and a WDH and installed the hitch to our Dakota receiver.  That dealer, is responsible for making sure that the receiver, the trailer, and the WDH all are within design limits and if I got killed as a result of the incompatibility of the three components, he's got to pay the fair market value of my continued existence on this planet to my survivors.  Though it wouldn't do me much good, my survivors would relish in receiving the $7.99 of value my life had, less, of course, attorneys fees and costs of litigation.  


-------------
Never leave footprints behind.
Fred & Maria Kearney
Sonoma 167RB
Our Pod 172
2019 Ford F-150 4x4 2.7 EcoBoost


Posted By: poston
Date Posted: 01 Sep 2018 at 11:56pm
Originally posted by BVK

 I just remind myself that, if I'm going the speed limit, I'm not a slow vehicle.

I would say that if you're driving the speed limit with vehicles following you, you might not be speeding, but you are a slow vehicle.

Washington law defines a slow vehicle as one "... which is proceeding at a rate of speed less than the normal flow of traffic at the particular time and place."  It doesn't say less than the speed limit.

Aside from the law though, I think it's uncommon courtesy to just pull over and let people by, whether you're pulling your Pod or driving your Maserati.



-------------

--
Jim
Virginia City, Nevada
2016 R-pod 180
2015 Nissan Xterra Pro-4X


Posted By: offgrid
Date Posted: 02 Sep 2018 at 6:26am
GlueGuy,

First, its really very easy to get a tongue weight of 600 plus lbs on a 179. Dual batteries, dual propane tanks, and a full fresh water tank does it. Lots of folks on this forum have those mods. 

Consider that the WD hitch is effectively creating a bridge between the trailer axle and the TV front axle,so if you really wanted to you could lift the whole rear axle of the TV off the ground with a strong enough WD hitch. The relocated load is therefore not limited to the tongue weight, its limited by the moments (torques) you apply to the system by cranking tension on the wd hitch. 

When you crank on the tension you are creating two moments, both acting around the ball, one pushing the trailer axle down, and one lifting the TV rear axle and pushing the TV front axle down. Basic statics analysis tells us that these are equal and opposite moments because otherwise the whole rig would continue to rotate.

These moments act around the ball so the load moved to the trailer axle is easy to calculate. Its just the ratio of the distance from the ball to the chains divided by the distance from the ball to the trailer axle, multiplied by the hitch tension applied. For a 179 with 30 inch wd bars this is about 0.2 so about 20% of whatever you tension the hitch to goes to the trailer axle. So you are correct that the difference in the two moment arms limits the load moved to the rear axle. But  note that this is independent of the tongue weight. So a 1000 lb wd tension gives you a moment of 2500 ft-lbs which results in about an extra 200 lbs at the trailer axle. 

The load moved to the TV axles is a little harder to calculate (junior high algebra required!) because you have to balance both the weight being moved from the TV axles to the trailer axle (the 200 lbs in the case above) as well as the 2500 ft-lbs moment acting around the ball. The link I provided to the wd hitch calculator earlier does this for you and also gives cute little dials showing how much reserve you have for each item. 

BTW I confirmed the calcs by running my rig through the public scales axle by axle with and without a (very high) wd hitch tension and sure enough, the calcs and real world loads agreed. Ain't science wonderful?

I had deliberately over tensioned the hitch to achieve a level TV. Turns out I had about 1200 lbs tension on my hitch, which is right at its rated capacity.  Would I drive around like that other than to do the experiment? Heck no. Bad for the trailer axle, bad for the trailer frame, bad for the wd hitch, bad for the receiver, and unnecessary for the TV, which can handle more rear axle load than front axle load.  

So the practical  point here is you should not try to use your wd hitch to level your TV. Follow the directions, which suggest using it to bring back the height of the TV at the front axle to what it was prior to connecting the trailer.  That should get the front axle load back to about its original unloaded level. 


-------------
1994 Chinook Concourse
1995 RV6A Experimental Aircraft
2015 Rpod 179 - sold


Posted By: lostagain
Date Posted: 02 Sep 2018 at 9:59am
Moral of the story, use a WHD that is sized for the TV and trailer, read and follow the directions for the WHD hitch and don't overload the tension bars, and don't exceed the towing weight capacity of the TV or the GVW of the trailer.  We have small trailers with limited capacity, so if you want to bring along your recliner and a 60" television buy a bigger trailer.  rPods are designed for relatively minimalist and simple camping, but we can enjoy many beautiful campgrounds that the big guys can only drive by and admire.  

As for the slightly off topic issue about pulling over for faster traffic, as a matter of common courtesy (referred to as "uncommon courtesy" by poston, likely because not enough people do it) pull over and let people pass no matter what your speed is relative to the speed limit.  It lessens the tension in your neck muscles (that have the same principles of physics that offgrid so eloquently explained) and you'll feel a lot better not to mention will reduce your chances of being involved in a road-rage incident.


-------------
Never leave footprints behind.
Fred & Maria Kearney
Sonoma 167RB
Our Pod 172
2019 Ford F-150 4x4 2.7 EcoBoost


Posted By: JR
Date Posted: 15 Feb 2019 at 8:45am
I am a newbie just got our 179 in August of 2018 and we live in Michigan and have set up the trailer the way we want too.  We are planning on getting out of this snow to warmer climates (Florida and New Mexico).  With all that said I finally got around to having the rig weighted yesterday and have a question even after reading most the posts on the forum concerning tongue weight.  I am pulling the r-pod with a 03 Jeep Grand Cherokee no problem there with the gross weight of the rig.  I am not using a wdh and have a tongue weight of 450 lbs, finding that weight by weighing the tv without anything hooked up to it then attaching the tt to the tv and weighing just the tv axels (2) and the difference is the tongue weight.  Got that.  Then I pulled the tv and tt on the scale (all 3 axels) and found out when I subtracted the tv's weight from the total rig I found out that I was just over the axel rating of 3500 lbs.  Also impacting the weight is when I weighted the rig I had snow load on top of the r-pod, guessing that load to be about 200 lbs and taking that load away from the gross weight of the rig gives me a little breathing room.  And yes we treat our r-pod very poorly in Michigan, allowing the snow to accumulate on the roof.

Here's my question to calculate the tt axel load do you subtract the tongue weight and tv weight from the gross rig weight to determine the load on the axel of the tt??  That would seem to be logical to me, but what do I know.  That's the reason for the question.  Any help would be appreciated and I have load range D tires so that should not be a problem.

Thanks in advance
Jay



-------------
Jay

179/2019


Posted By: furpod
Date Posted: 15 Feb 2019 at 10:08am
If you are not using a WDH, the axle weight is the axle weight. No calculations needed.

But it appears you didn't weigh the Pod axle. So, at this point, you can subtract the tongue weight you calculated from your gross weight, and the empty unhooked weight of your Jeep, and that will give you, if everything was straight and level, etc when the weights were done, a calculated axle weight. I don't see why you didn't weigh the TT axle, that sure would answer your question.


-------------


Posted By: JR
Date Posted: 15 Feb 2019 at 10:35am
You are correct hind sight is very clear to me.  Just thought that I could use the calculations to come up with what I needed.  Thanks again.

-------------
Jay

179/2019


Posted By: offgrid
Date Posted: 15 Feb 2019 at 10:55am
Not to worry JR, furpod is right, just subtract the total rig weight from the weight of the TV with the trailer attached and that is your trailer axle weight. 

With no wdh the rig doesn't really need to be totally level. If you were using a wdh then if the rig wasn't on a completely flat surface the tension on the wdh would create some errors. But with no wdh the total error won't be more than 2x the scale accuracy, which is usually +-20 lbs or so. If you're worried about being off by at most 40 lbs then you're too close to the limits anywayWink


-------------
1994 Chinook Concourse
1995 RV6A Experimental Aircraft
2015 Rpod 179 - sold


Posted By: JR
Date Posted: 15 Feb 2019 at 11:59am
Thanks all the light bulb came on when I thought that I had to subtract the tongue weight with the tv's weight to get the trailer's axel weight.  Just wanted to make sure I wasn't missing something.  I do have enough breathing room on the trailer's axel weight to enjoy our trip coming up next week.  Thanks again furpod and offgrid.


-------------
Jay

179/2019



Print Page | Close Window

Bulletin Board Software by Web Wiz Forums® version 9.64 - http://www.webwizforums.com
Copyright ©2001-2009 Web Wiz - http://www.webwizguide.com