Date: Thu, 23 Aug 2001 08:41:45 -0600
Reply-To: John Klun <jklun@GJ.NET>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: John Klun <jklun@GJ.NET>
Subject: Re: Trailer Fishtailing...
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Walt and friends-
We tried to be very careful about load distribution on the trailer. If we had
had any more weight on the hitch, we would have been dragging our bumper... :)
I failed to mention in my long epistle that speed was an additional factor in
our 'swaying/fishtailing'. I did notice that if I maintained a speed of around
55-60mph on the 'grooved' roads, the trailer had less inclination to fishtail.
But that didn't matter at all when an 18-wheeler or even a large motor home
passed us- it would start us fishtailing for at least a quarter mile. After a
while of this punishment, we began to anticipate the passing 18-wheelers by
pulling half onto the shoulder- this provided us with a little more stability.
We did see some 18-wheelers swaying/fishtailing ahead of us on the road we were
traveling and that made us very nervous...
Walt Spak wrote:
> John & list,
>
> What you are calling fish tailing sounds like what I call sway. It is a
> result of improper load distribution on the trailer. There was too much
> weight towards the rear, which resulted in too little weight on the tongue
> of the trailer. I learned this lesson years ago when hauling cars on
> various flat bed trailers. I even had a van & loaded trailer turn 180
> degrees around on the Ohio Turnpike. It is interesting to sit in the middle
> of the road & watch traffic coming at you. The highway wear & rain grooves
> affected your tow because of the improper distribution, but were not the
> cause.
>
> I do not remember exactly how much weight you want on the tongue & I believe
> it changes with the trailer size & weight and the hitch class. Proper
> tongue weight is very, very, very important.
>
> Walt Spak
> Pittsburgh, PA.
> wnsopc3@3rdm.net
>
> ----- Original Message -----
> From: John Klun <jklun@GJ.NET>
> To: <vanagon@GERRY.VANAGON.COM>
> Sent: Wednesday, August 22, 2001 1:23 PM
> Subject: Trailer Fishtailing...
>
> > Hello Volks-
> >
> > A few days ago, someone sent a posting about their fishtailing problem
> when
> > hauling a trailer. Here's my two cents worth. (Alas, not really Vanagon
> > content but applies...)
> >
> > About 2 weeks ago, I had the 'opportunity' of hauling, from Dallas, TX to
> > Delta, CO, an 18'X7' trailer (weighs about a ton) loaded with about 2-3
> tons
> > of equipment behind a Ford F-150 X-Cab with a (get this) 302CID engine-
> and
> > an automatic to boot! Yikes! We found out later that the trailer brakes
> > were not working or even installed. Dumb and Dumber!
> >
> > There was so much weight behind us and so little power, it took forever to
> > get up to speed. We also suffered from that 'harmonic' fishtailing that
> was
> > mentioned. We found it was set off by the difference in wheel widths
> (truck
> > 6', trailer 8') going over rutted highways. All the way from Dallas to
> > Clines Corners, NM, the highways had grooves in them from heavy trucks
> > driving in the same spots. We also noticed that the fishtailing was
> caused
> > by too high a speed and trucks passing us at high speed- especially with
> > high cross winds.
> >
> > We didn't seem to have any problems wherever the roads had fairly fresh
> > asphalt laid down- such as I-40 in New Mexico.
> >
> > The scariest moment I had was when we were traveling, balanced steady, in
> > the grooves at around 65 (speed limit was 75) when we were passed by an 18
> > wheeler doing about 80 and there was a crosswind blowing from the driver's
> > side. We immediately started fishtailing so bad that I thought I was
> going
> > to lose it. Nothing that I did could stop it and only made it worse. I
> > kept over correcting without trying to. Finally I resigned myself to the
> > possibility that it was all over and let up on the wheel. Lo and behold!
> > The fishtailing reduced dramatically! And I was finally able to get it
> > under control. Yes, I did let up on the gas but not enough to jack knife
> > and yes, I kept my foot off the brakes for the same reason. The only
> other
> > thing that I noticed that helped besides taking my hands off the wheel was
> > steering the truck and trailer half on/half off the shoulder. That
> steadied
> > the fishtailing some. Next time- it will be a heavier truck with a more
> > powerful engine.
> >
> > Surprisingly, we didn't have much of a problem on the mountain passes.
> > Obviously, with that heavy a load, we were in 1st gear all the way to the
> > top at around 10-15 mph. I kept it in 1st gear on the way down as well
> > never letting our speed get more than 30 mph over our base speed. I
> braked
> > heavy to get down to the base speed and continued doing that until the
> road
> > leveled off enough to shift into 2nd/3rd. The brakes were fine coming
> down
> > this way. There was one 8,000' pass where I got very cocky and didn't
> leave
> > it in 1st long enough coming down (it was steep) before shifting. We paid
> > for that by almost losing it and when we finally stopped in a pull off,
> the
> > brakes were glowing red in the dark and the right one was smoking like it
> > was on fire! That's when we found out we had no trailer brakes... (don't
> > ask). After that episode, the trip was very uneventful.
> >
> > John
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