Increasingly severe sway

[frank r]

I have a 2019 2920BH which I tow with a 2009 Expedition. From the day I switched from a Tahoe to the Expy, I noticed it swayed more, which was to be expected with the Expy's IRS.

However, mid-way through last season, I noticed the sway becoming worse, and at the end of last season, it got to the point where I had to stay under 60mph, and any passing truck induced a white-knuckle moment. This year, I replaced the rear struts on the Expy (I knew at least one of them was bad) and added a pair of Sumo Springs, hoping that this would help.

Just got back tonight from a short weekend trip, and the sway is as bad as ever, if not worse than I remember. I have a Reese WDH, which I believe is set up properly. The tires on the TT and TV are inflated properly, and the lugs are all tightened to spec. On its own, the TV seems to ride just fine, with no hint of ride quality issues. When I got home tonight, I checked wheel bearing play - I was able to get just a hint of lateral movement in all 4 wheels, but nothing that seemed to be cause for concern. Would loose wheel bearings on the TT cause my issues? I'm sure I could snug these up a bit, but I'm concerned about overtightening.

Any input on where else to look would be greatly appreciated. Just for context, I've been towing larger TTs for 25 years with all sorts of TVs, so I am definitely not imagining this.

Thank you.

[jasin1]

Originally Posted by frank r

I have a 2019 2920BH which I tow with a 2009 Expedition. From the day I switched from a Tahoe to the Expy, I noticed it swayed more, which was to be expected with the Expy's IRS.

However, mid-way through last season, I noticed the sway becoming worse, and at the end of last season, it got to the point where I had to stay under 60mph, and any passing truck induced a white-knuckle moment. This year, I replaced the rear struts on the Expy (I knew at least one of them was bad) and added a pair of Sumo Springs, hoping that this would help.

Just got back tonight from a short weekend trip, and the sway is as bad as ever, if not worse than I remember. I have a Reese WDH, which I believe is set up properly. The tires on the TT and TV are inflated properly, and the lugs are all tightened to spec. On its own, the TV seems to ride just fine, with no hint of ride quality issues. When I got home tonight, I checked wheel bearing play - I was able to get just a hint of lateral movement in all 4 wheels, but nothing that seemed to be cause for concern. Would loose wheel bearings on the TT cause my issues? I'm sure I could snug these up a bit, but I'm concerned about overtightening.

Any input on where else to look would be greatly appreciated. Just for context, I've been towing larger TTs for 25 years with all sorts of TVs, so I am definitely not imagining this.

Thank you.

How does the axle look on the TT? Did you ever hit a particularly bad pothole or possibly bend an axle? Or twist it@?

[frank r]

No apparent damage to any part of TT or TV. Never hit any curbs, major potholes, etc. Tires are like new on both. TT has maybe 3000 miles on it, probably less.

When we were on the interstate coming home tonight, my wife (following in her car) pulled up along both sides of the TT, and did not see anything out of the ordinary - even while the TT was wandering like crazy.

[jasin1]

Someone will chime in with more experience

[frank r]

Just for clarification - the bearing play I mentioned was on the TT, not the TV.

[JRTJH]

What we have here is the "proverbial half ton truck with a too big trailer" syndrome....

The Expidition is, by most definitions, a short wheelbase single cab half ton pickup with an integrated bed cover and more seats than a single cab truck...

The Expedition (standard length) wheelbase is 122.5"
The Expedition (long version) wheelbase is 131.6"

The F150 regular cab/6.5' bed truck wheelbase is 122.8" (the shortest F150 Ford makes) which is 0.3" longer than the Expedition)
The F150 crewcab 6.5' bed wheelbase is 157.2"

So, towing a 33' trailer behind a "short wheelbase vehicle" is always going to change the "fulcrum point" on the seesaw, causing the front of the tow vehicle to "wiggle" when the rear of the trailer "wags"...

Now, there are some things to consider as well as wheelbase:

1. The tires on the Expedition are probably "P" series tires with a soft sidewall. They will allow significantly more "tire squirm" as the trailer pushes the truck from side to side.

2. The distance from the Expedition rear tires to the hitch ball and the distance from the hitch ball to the trailer tires will have a great influence on how the "lever action" reacts to the trailer lateral movement. What that means goes back to the general rule: "The shorter the tow vehicle wheelbase, the more sway will be felt with any trailer movement".

3. Have you actually "gone across a CAT scale to get accurate weights" ???
If you have not, you might consider doing so. You might be at/close to/over your Expedition payload. Additionally, trailer loading may be influencing your sway and causing or adding to the problem. Most people recommend a 10-15% tongue weight for the trailer. Some trailer/vehicle combinations are "squirrely as hell" at 10% and "rock steady" at 15%. It's hard to know "where your combination sits on the tongue weight percentages without an accurate weight.... It might be as simple as "airing your "P" series tires to the max sidewall value (and accepting the center tread wear as a necessary evil) or it might be "just loading the trailer a bit differently", or possibly hanging the "P" series tires for LT tires and accepting the reduced fuel mileage and increased harsh ride when empty...

Then again, it may be a combination of wheelbase, trailer length, tongue weight, tires and hitch setting, all of which simply can't be managed....

Take a look, first at your weights, then tire pressure/tire type, and finally, trailer loading... Hopefully it's as simple as adjusting one or two of the above...

But that said, your short wheelbase half ton vehicle is not an "ideal" or even a "recommended" tow vehicle for a 33' travel trailer, even though it's below the "brochure maximum trailer recommended weight rating".....

ADDED: If you have a friend with a 3/4 ton truck, hitch the trailer to his truck and see how it performs. I'm sure you'll see all the "sway issues" resolved. That will narrow the possibilities by eliminating the trailer as a part of the problem....

[jasin1]

I don’t know why but I was picturing a Ford excursion not an expedition. Excursion is more like a 3/4 ton truck.
I relayed a story a while back of my neighbor switching to a fifth wheel after his short wheelbase ramcharger and TT was wrecked.He was entering the Baltimore Beltway and out of nowhere it started violently swaying and before he could do anything,it swung around and flipped over.
Luckily the trailer detached but it still totaled the tv as well.

[frank r]

JRTJH – thank you for taking the time put together such a thorough response.

Let me start by saying that I agree 100% with what you have said. I knew when I chose my TV that it wasn’t going to be perfect. Between the short WB and IRS, I knew it wasn’t going to be rock solid – but it was the type of vehicle that I needed and was willing to accept the compromise. For the 1st year or so, it really was fine (again, not perfect) – but it is getting worse with each trip since about the mid-point of last season.

You are correct, the tires on the TV are “P” series, and they are inflated to the max cold pressure listed on the sidewall (44psi). The tires on the TT are inflated to their max cold pressure as well (65psi).

I have yet not had the rig on a scale. What measurements will I need – weight of TV alone, weight of TT alone, and weight of TV plus TT (with TT wheels not on the scale)? Anything else? I only have one scale semi-locally that I know of, not sure how patient they will be with taking multiple measurements and allowing me to hook/unhook.

I guess the question I keep coming back to is why is the sway becoming more severe? I have not made any changes to loading, so the tongue weight should not have changed measurably. Last night I made a small adjustment to the hitch setup – since the Sumo springs should decrease the amount of sag, I pitched the head back towards the TT slightly. This should allow me to use an extra chain link on the spring bars which I believe should give me a bit more sway control.

With regards to the TT wheel bearings, I am not familiar with the axles on this rig – can anyone refer me to the proper method to making sure the wheel bearings are adjusted properly? I have a short trip coming up later this week, and would like to check these out before I pull out.

Thank you.

[flybouy]

I think you need to get the tv to a good suspension shop. Have them get it on the lift and check everything out. If nothing has changed with the trailer regarding loading, ect. then investigate the truck. With a 12 yr old vehicle you could have significant wear on bushings, steering components, even body mounts. It's all one system and if one component is compromised it will effect handling, especially at max loads (and therefore max strain stressing the capability of an already compromised situation with an inherent "tail wagging the dog combination). From your narative it sounds like the issue is progressivly getting worse and was not a "sudden onset" like a change in loading the trailer would have. A worn tie rod, ball joint, A arm bushings, etc. will get progressivly worse and will be magnified under the stress.

[cavie]

Are you using a sway bar? Reese WDH does not have sway control. This is a Curt but the same thing. Some folks will run this without the sway bar.

[frank r]

I use a Reese dual cam setup with integrated sway control.

[frank r]

I believe flybouy is on the right track here, and this is what I have been thinking was potentially behind this issue. I really need to do some research into someone in the area I can trust.

We have been playing around with the idea of replacing both the TV and TT, as this TT is having water issues (see an old post of mine from last year). I was really hoping to get through this year with what we have, but maybe it’s time to cut our losses and start over.

[German Shepherd Guy]

I think, as do you I see, that Marshall is on the correct track. Also you will not believe the difference that LT tires will make over P tires. I ran 10 ply equivalent on my 1/2 ton suburban when I was towing with it. That said though, the tire change does not account for the sway getting worse and would be a band-aid not a fix. Good luck, sounds like you are talking yourself into a TT and a TV change. Let us kow what you end up with.

[Ken / Claudia]

We are all guessing and tossing out possibilities, mine is not much different than others.
After post #1, I thought of 3 things that should be done. Easy no cost is, have a friend with a 3/4 ton truck give it a test pull and let you drive. If no problems you ruled out your hitch and the TT.
LT tires properly inflated on a tow vehicle pulling a large load is a must in my book. They will help. Doing that will give you a better towing experience. Will they end all your problems, I doubt it.
Suspension on all vehicles wears out. You have been stressing yours more than most would with that size of TT. Replacing all parts will be costly, might get you back to where you were when you started.
In the end it's up to you, it's where to you want to spend your money. I would quit trying to make the TV better and just buy a better TV.
I did repairs/ upgrades just a few years ago on a vehicle and beleive me LT tires over P tires preform better, the 1st turn from 1 street to another, it was a no brainer the LT tires perform much better. Short time later I had all suspension parts replaced and the vehicle showed a massive improvement. At the cost of about 4,000 dollars. That was a SUV I only towed my boat with locally. Mostly it was the daily driver. All that spend and I still could only get 2500 for the vehicle at resale a year later.

[JRTJH]

You said you hadn't yet weighed your rig and expressed some confusion about how to do it and where to do it.

If you have access to a single platform or a double platform scale in your local area, you can modify these instructions.

All CAT scales are a "3 platform scale". The closest one to you is the FUEL ON TRUCK PLAZA located at exit 143 on I-81 in Hazelton.

If you choose to go there to weigh, when you arrive, go inside, ask to speak to the weighmaster. Explain to him/her what you're trying to do (get comprehensive weights for your RV rig). He will then be aware of your objective and can help you through the process....

Scale "etiquette" is important, truckers are the main client using the scales and they are busy, so NEVER DILLY AROUND ON THE SCALES ...

After discussing the plan with the weighmaster, drive onto the scale platform and stop with the TV front axle on pad 1, the TV rear axle on pad 2 and both trailer axles on pad 3. STAY IN THE TRUCK and press the button to get your weight recorded.

Then, get out of the truck, loosen the WD bars on the hitch so there is no tension (DO NOT REMOVE THE BARS) get back in the truck and press the button for the second weight. When that is recorded, drive off the scales, to a convenient "OUT OF THE WAY" spot and unhitch the trailer.

Drive back onto the scale and stop with the TV front axle on pad 1 and the rear TV axle on pad 2. Press the button and get your third weight recorded...

Drive off the scale and go inside to "settle up and your your weight tickets"..

Total cost will be $12.50 for the first weigh and $3 for each reweigh (on the same day) for a total cost of $18.50.

Once you get those three weights, you'll have the following:

TOTAL RIG WEIGHT
Total weight on each axle
Total weight applied by the WD hitch to the front axle and the trailer axles

Releasing the WD bars will give you
Total weight on front axle without WD bars (will be less than above)
Total weight on the rear axle without WD bars (will be more than above)
Total weight on trailer axles (will be less than above)

TV alone will give you
Total weight of TV
Total weight of TV front axle
Total weight of TV rear axle

Using simple math you can calculate:
Hitch weight both with and without WD weight transfer
Amount of weight transferred to front axle and trailer axles with WD hitch tension
Remaining cargo weight capacity based on vehicle weight/GVWR and trailer cargo capacity based on trailer weight/GVWR.


There is a lot more information you can calculate, but that's enough to get you started. Knowing the weights will allow you to immediately determine if there is an overweight condition that might affect your vehicle. It will also show you where the "increased stress of trailer weight" is being applied to your tow vehicle and may help explain why/which parts are being stressed, possibly causing the increased wear pattern you suspect in your suspension.

[travelin texans]

Most all of those type SUVs, regardless of brands, were designed to be people mover grocery getters not for towing long tall heavy loads. Typically they had barely enough payload to fill all the seats with people before adding weight to the hitch.
Before you dump a lot of $$ into a 12+ year old vehicle that may or may not help the situation you may want to upgrade sooner than later to a better suited tow vehicle.

[frank r]

JRTJH – thank you for the comprehensive input on what I will need at the scales. The one you mentioned is the one I knew about in the area and I will be passing it on Thursday morning, so maybe I will leave a bit early and stop in. The only issue I see is that I will not have any passengers in the vehicle, so that aspect of the weight will be off.
A lot of folks are advocating for a better TV, and I do not disagree. While I know a ¾ ton pickup is my ideal TV, it would be very difficult from a family hauling perspective. I generally travel with my wife, 13 year old son and 2 large dogs (80 and 140 lbs) – I can’t imagine how this would work even with a crew cab pickup.

[JRTJH]

You could always put a cap on the truck bed, tie down two dog kennels in the bed and your son would have the entire back seat of a crew cab. With a sliding rear window, you could keep cool air flowing into the rear cap area with one of the "inflatable rings" to seal the space between the truck rear window and the cap front window.

While not ideal travel arrangement, neither is your current situation... Sometimes to achieve the "satisfactory end result" compromises along the way are pretty much mandatory. My "ideal rig" is one that gets me from where I am to my destination with only time spent along the way "where we want to stop"... All that "extra driving, extra sitting in one seat for hours, etc" just turns into "we are there" with no "how much further do we have to go?".... It's not that I don't dislike sitting in a truck for 8 hours, but it's not the most enjoyable way to spend a day.... I'd much prefer to "wake up, get in the truck, start it and be at my destination already".... but alas, we all have to "make compromises along the way"....

[frank r]

Or, I could put the wife and kid in kennels in the bed and the dogs can ride up front.

Just sayin...

[Ken / Claudia]

Let me know if that trick works. I would like to try it also. My lab never talks back complaints about my driving. He just wants a window cracked open at times to smell what's outside.