trailer sway mitigation TSM

On Tuesday, December 17, 2019 at 5:51:09 AM UTC-8, Glidergeek wrote:
Longer wheelbase on the towing vehicle with a robust suspension.

Perhaps an even more important metric is the ratio between the wheelbase and the distance from the rear axle to the hitch ball. Long wheelbase with the hitch close to the axle is best. Short wheelbase with long distance between the rear axle and hitch gives the trailer more leverage over the car, and the car less leverage against the ground to resist lateral disruption.

--Bob K.

Dave Nadler wrote on 12/17/2019 11:30 AM:
On Tuesday, December 17, 2019 at 2:01:56 PM UTC-5, Eric Greenwell wrote:
Boise Pilot wrote on 12/17/2019 10:19 AM:
On Tuesday, December 17, 2019 at 10:15:29 AM UTC-7, Jonathan St. Cloud wrote:
On Tuesday, December 17, 2019 at 8:06:29 AM UTC-8, Matt Herron Jr. wrote:
On Monday, December 16, 2019 at 4:43:23 PM UTC-8, JS wrote:
Good shocks seemed to have the biggest effect in my experience.
I have used three different model year Jeep Grand Cherokees as tow cars for
over 35 years. Nelson Funston (JN) is a tire and trailer expert with big heavy
trailers. With my first Jeep, told me to do three things in following order:
-Move some weight forward,-stiffer sidewall trailer tires at max pressure,
-vehicle tires at max pressure. Ancillary advice, maintain Jeep shocks... We
have some interstate speeds of 80 mph in Idaho. No sway!! All my Jeeps were
the 8cyl model so heavier than the old 4cyl and most currently available 6cly
on the road. Also all had 4 wheel drive and the off road accessory that has
different suspension and road clearance. Boise Pilot




Look out when moving trailer weight forward... Never exceed the maximum
tongue weight! Jim

Also tighten up the hitch in the receiver with one of these: they take out
the slop that can add to sway, and quiet down the rig

I found once I stopped towing with a Jeep Grand Cherokee I had no more sway
problems.

Anyone that wants to hear more from Nelson Funston can download his OSTIV paper on
trailer stability he

http://journals.sfu.ca/ts/index.php/...wnload/779/737

Anybody convert that model to a nice Excel spreadsheet?

About 8 years ago, I talked to Nelson about using the code; problem was, it was
written in an old version of FORTRAN (IIRC) that hadn't been supported for a long
time, and he didn't know any way to easily ["easily" being the important word]
convert to something that was supported. I've sent you an email with his email
address, so you can discuss it with him. I'd like be able to run it, too.


--
Eric Greenwell - Washington State, USA (change ".netto" to ".us" to email me)
- "A Guide to Self-Launching Sailplane Operation"
https://sites.google.com/site/motorg...ad-the-guide-1

On Tuesday, December 17, 2019 at 10:19:03 AM UTC-8, Boise Pilot wrote:
On Tuesday, December 17, 2019 at 10:15:29 AM UTC-7, Jonathan St. Cloud wrote:
On Tuesday, December 17, 2019 at 8:06:29 AM UTC-8, Matt Herron Jr. wrote:
On Monday, December 16, 2019 at 4:43:23 PM UTC-8, JS wrote:
Good shocks seemed to have the biggest effect in my experience.
I have used three different model year Jeep Grand Cherokees as tow cars for over 35 years. Nelson Funston (JN) is a tire and trailer expert with big heavy trailers. With my first Jeep, told me to do three things in following order:
-Move some weight forward,-stiffer sidewall trailer tires at max pressure, -vehicle tires at max pressure. Ancillary advice, maintain Jeep shocks.... We have some interstate speeds of 80 mph in Idaho. No sway!! All my Jeeps were the 8cyl model so heavier than the old 4cyl and most currently available 6cly on the road. Also all had 4 wheel drive and the off road accessory that has different suspension and road clearance. Boise Pilot




Look out when moving trailer weight forward... Never exceed the maximum tongue weight!
Jim

Also tighten up the hitch in the receiver with one of these: they take out the slop that can add to sway, and quiet down the rig

I found once I stopped towing with a Jeep Grand Cherokee I had no more sway problems.

Another simple driving tip is to use both hands on the steering wheel and brace your elbows on the arm rests. This will prevent any body sway (such as getting a side wind gust) from aggravating the stability problem.

Tom

Nelson customized a number of his trailers over the years for extreme towability. The best by far was an LS4 aluminum clamshell trailer that had been turned around so the glider loaded and unloaded over the tongue. Moving the heavier parts of the glider to the back allowed placing the axle further aft while maintaining a reasonable tongue load. Nelson delighted in towing it with his wife’s Datsun F10. The poor little F10 was quite stable, but excess speed was never a problem. I towed it myself with a number of smaller vehicles and the trailer was essentially unnoticeable except when accelerating or slowing down.

This is an option for many of our trailers, but the market reality is we’re willing to sacrifice stability for the convenience of not assembling over the tongue.

Craig
7Q, JN

On Tuesday, December 17, 2019 at 7:50:37 PM UTC-6, Craig Funston wrote:
Nelson customized a number of his trailers over the years for extreme towability. The best by far was an LS4 aluminum clamshell trailer that had been turned around so the glider loaded and unloaded over the tongue. Moving the heavier parts of the glider to the back allowed placing the axle further aft while maintaining a reasonable tongue load. Nelson delighted in towing it with his wife’s Datsun F10. The poor little F10 was quite stable, but excess speed was never a problem. I towed it myself with a number of smaller vehicles and the trailer was essentially unnoticeable except when accelerating or slowing down.

This is an option for many of our trailers, but the market reality is we’re willing to sacrifice stability for the convenience of not assembling over the tongue.

Craig
7Q, JN

Moving the axle further aft means you sacrifice the trailer's maneuverability at narrow street corners - you will drag it over curbs and sidewalks, possibly hitting lamp posts. I think the axle position is part of the compromise that professional trailer manufacturers like Spindelberger take into account.

On Monday, December 16, 2019 at 12:03:02 PM UTC-8, princiar wrote:
Anyone has experience towing a trailer with a car with the trailer sway mitigation installed?

I used to tow a DG 800 with a single axle trailer with a 4 Runner and found it got to be quite a adventure. Any rapid turning would end up with a sway side to side. I now tow with a Range Rover with 20" wheels with low profile tires. The difference is night and day. IT was easy to understand the the major difference is the tires. The 4 Runner had a high profile tire that flexed if you pushed side to side on the rear of the car. The low profile tires have virtually no sidewall flex. The suspension in the 4 runner was solid with great sway bars, they however could not over come the flexing in the tire sidewalls. In the Rover I can easily go any speed I desire with zero sway and can change lanes at will. Push your car sideways at the rear and observe what you see. Any motion will reveal why you have sway. I have seen many work arounds with friction tuning to dampen sway, but none work better than addressing the root cause.

I have a newish VW Golf that has trailer-assist option. It has electronic stability system for trailer towing, including fancy servo steering that points the trailer directly to direction you want when reversing.

All I can say is that it goes like a train on rails and I have never had slightest indication of swaying.

At 07:35 18 December 2019, krasw wrote:
I have a newish VW Golf that has trailer-assist option. It has
electronic
stability system for trailer towing, including fancy servo steering that
points the trailer directly to direction you want when reversing.

All I can say is that it goes like a train on rails and I have never had
slightest indication of swaying.
Hi,
You should have a look at this, I think it explains a lot.

At 07:35 18 December 2019, krasw wrote:
I have a newish VW Golf that has trailer-assist option. It has
electronic
stability system for trailer towing, including fancy servo steering that
points the trailer directly to direction you want when reversing.

All I can say is that it goes like a train on rails and I have never had
slightest indication of swaying.

At 07:35 18 December 2019, krasw wrote:
I have a newish VW Golf that has trailer-assist option. It has
electronic
stability system for trailer towing, including fancy servo steering that
points the trailer directly to direction you want when reversing.

All I can say is that it goes like a train on rails and I have never had
slightest indication of swaying.
Hi,
You should have a look at this, I think it explains a lot.