Towing Porpoising

[Andy543]

Originally Posted by Ndcctrucks

Try towing on the ball only.

-Ken

I agree. These single axle trailers don't do well with weight distribution hitches. I'm pretty sure the porpoising situation will improve by eliminating the hitch. The Jeep should be able to handle this small trailer without it.

[ROBERT CROSS]

Originally Posted by Andy543

I agree. These single axle trailers don't do well with weight distribution hitches. I'm pretty sure the porpoising situation will improve by eliminating the hitch. The Jeep should be able to handle this small trailer without it.

Yep...I used a Reese Straight Line WD for 18 seasons on our '63 Safari and it porpoise'd all over the USA...

NOT

Bob
🇺🇸

[Tim A.]

Originally Posted by Andy543

I agree. These single axle trailers don't do well with weight distribution hitches. I'm pretty sure the porpoising situation will improve by eliminating the hitch. The Jeep should be able to handle this small trailer without it.

Originally Posted by ROBERT CROSS

Yep...I used a Reese Straight Line WD for 18 seasons on our '63 Safari and it porpoise'd all over the USA...

NOT

Bob
🇺🇸

Yep, our poor trailer has suffered for over 20 years with that darned Hensley hitch, complaining the entire time that we should be towing it on the ball.

RIGHT

[Boxite]

I tow many thousands-of-miles on the ball with my 22’ single-axle and it does fine, never a problem. (I do have a friction anti-sway bar for extra safety, but didn’t have anything for the first 10K miles. High-winds/I-10/West-Texa 18-wheelers is what the anti-sway helped mostly, but otherwise, it did fine.)

[ROBERT CROSS]

Originally Posted by Boxite

I tow many thousands-of-miles on the ball with my 22’ single-axle and it does fine, never a problem. (I do have a friction anti-sway bar for extra safety, but didn’t have anything for the first 10K miles. High-winds/I-10/West-Texa 18-wheelers is what the anti-sway helped mostly, but otherwise, it did fine.)

Airstreams...the best TETO RV.

“If you’re happy with what you’re doing…all is good.
If other people are unhappy….it’s not”
RLC

Bob
🇺🇸

[Wazbro]

Originally Posted by Boba911

I also thought that the hitch would make a biggest difference set properly. This is why I call CAMCO service and explained my problem. The Jeep Gladiator does have a stiff suspension which I don't want to change. I do believe that the hitch will do the trick but we will see. Also I did tow a 23ft AS duel axil FC with no problems and used an Equalizer hitch setup. The hitch was noise but no porpoising. Does a trailer with 2 axils not have this problem?

2 axle trailers CAN have this problem.

[rmkrum]

Originally Posted by Wazbro

2 axle trailers CAN have this problem.

Definitely. My 22’ dual axle 2007 International CCD WILL easily porpoise if I don’t dial in enough WD tension.

[ROBERT CROSS]

Not all porpoising is trailer related...road harmonics can be a real PITA.

We had a stretch of concrete on the NYS Thruway that no amount of trailer fiddling would correct.
Finding the correct speed was the only way to reduce it, nothing would eliminate it.

Bob
🇺🇸

[barts]

The porpoising problem is this: The TV rocking on it's suspension in the fore and aft direction, driven by bumps in the road, with the additional mass and weight of the trailer lowering the frequency and increasing the amplitude from the unloaded condition. Most of the time, it's tolerable, but certain sections of road driven at normal speeds can be pretty awful.

Since this is a classic underdamped resonant system, anything that changes the resonant frequency of the system or the frequency at which it's driven will help. So:

• Slowing down or speeding up may move the excitation far enough from the resonance point to make things ok.
• Increasing the damping (stiffer shocks) on the TV can help, but may make it too stiff when not towing.
• Air bags on the TV can move the resonance point enough higher to make the problem go away. This really helped our truck; it's a crew cab F250 and porpoised easily.
• WD bars will also affect the resonant frequency; they don't add damping but stiffer bars will move it up, more compliant bars will move it down. Either may help.

[jimfa440]

Originally Posted by Boba911

I have purchased a 2018 19 ft Tommy Bahama and it came with a Equalizer 14000# hitch setup. I tow with a Jeep Gladiator Rubicon and towed a 23 ft AS with no problems in the past. On the 19ft it seems to be porpoising a lot while towing. I have check the tow height of everything and all seen level. I am thinking that the 14000# spring bars in the hitch is too much for this light trailer?? Any advice will be greatly appreciated.

Your spring bars are way too heavy. You don't have enough weight on them to allow them to function. Go lighter, your Airstream will thank you.
Happy Camping

[HRTKD]

Front shocks weren't specifically mentioned, but if the front shocks are toast, that could contribute to porpoising. When I tow I bump my front Rancho 9000XL shocks up one setting (from 5 to 6), while the rear shocks get changed from 4 to 8 or 9 depending upon how heavy the trailer is loaded.

[Skrausestl]

1. The torsion bars are too stiff for your trailer weight by about 3X. This may be triggering a bounce. Fix this whatever else you do… it’s probably unsafe because it makes the whole rig harder to control particularly as speed increases. This is true for any weight distribution hitch. Changing hitch brands without correction the torsion bar stiffness will probably not help.

2. If trailer shocks are leaking, weak, old, or you don’t know how old, replace them. This should help damp out any remaining “bounce” and certainly will not hurt.

3. Ditto #2 for the tow vehicle.