Bucking while towing the Pinz?

[audiocontr]

Had a question about towing. I loaded my 712 onto my trailer and pulled it with a 2001 F250 diesel. The truck seemed to buck as we accelerated or simply coasted. I could see the trailer buck to the same rhythm. Is this an indicator of bad tongue weight? Would i usually need to locate the center of the pinz further back?

[David Dunn]

Without knowing exactly what "buck" is to you, my first guess is that you didn't have the proper tongue weight.... too much weight to the rear of the trailer's axles. tongue weight should be 10% to 15% of the total weight of the trailer.

[Erik712m]

Bucking Dave. http://real4x4forums.com/PinzgauerBBS/v ... ght=#23015

[David Dunn]

That's not what I was thinking of bucking, that is the results when you tie by the axles.... you can see the suspensions working against each other.... that is the video I was thinking of in AC's other thread.
Bucking can also be from the tongue lifting and falling as the weight shifts on the suspensions when there isn't enough to keep the tongue down.
Years ago, coming back from a SWPA treffen, I actually had the WD hitch twist the receiver hitch upwards, removing the tongue weight and causing something similar to me on a long downhill run. It was a 15k receiver that the manufacturer of the winch bumper/receiver had bolted that it took all the downward pressure of the trailer, but bent up from the force of the WD bars. When I got home, I added 2 strategically placed bolts plus bracing up to the frame

[audiocontr]

Nope, not that kind of bucking =)

Its a very rhythmic bounce. I'm guessing tongue weight as well. I will have to play a bit to find the right spot

[David Dunn]

Tongue weight....or lack of it.
Here is one way to figure what it is
http://www.etrailer.com/faq-trailertowtips.aspx

I have one of these.
http://www.sherline.com/lm.htm

But make sure you do it from the ball hitch and not the jack

[M Wehrman]

My trailer is level to start,so I use a yardstick leaning against my rear bumper. As I'm pulling up I look for appx 2" of bumper drop and call it good. This is with a 20ft car hauler trailer and a 4x4 Super Duty. Never an issue this way at any speed. Tounge weight is your friend!
Mark

[David Dunn]

That's not good for a general rule. Each truck suspension will drop at a a different rate. Super Duty is a class of Fords from F250 to F550, each with a different weight rating, also what cab and bed makes a difference in the wheelbase that also loads differently... also what load is in the truck already will change the level and the loading of the springs will not be progressively the same. Also the trailer length and the distance from the axles to the ball will play in geometrically.

The only way to be sure of the tongue weight is to weigh it.

But be sure the trailer rides level, on tandom axle trailers, if the front ( or rear) is greatly higher than the other, you will have loaded more weight onto the other axle, and possibly overload the axle or tires, generating more heat and leading to possible tire failure..... been there, don't want to do it again.

[Fleg]

My trailer is level to start,so I use a yardstick leaning against my rear bumper. As I'm pulling up I look for appx 2" of bumper drop and call it good. This is with a 20ft car hauler trailer and a 4x4 Super Duty. Never an issue this way at any speed. Tounge weight is your friend!
Mark

That's really not the best way to tell and Tongue weight is your friend up to a point. Generally 10-15% of the total trailer weight should be on the tongue. Too much and you'll destroy the tires on the trailer due to overloading. Too little and the trailer will wag and lurch.