M416 Trailer weaving from side to side

[maddawg308]

This is really moot, since I no longer own my old M416 trailer. However, I never figured out why this happened, and want to find out from you guys.

I had a 1996 Dakota that I loved, bought a M416 trailer in 1998 to ride behind it. Restored the trailer, owned it for several years, sold it in 2005. The trailer tracked great behind the Dakota, however, on some sections of interstate highway that were segmented (concrete, not asphalt), the trailer would begin to oscillate side to side, sometimes violently, above 65 mph. If I slowed down to 55 or 50, no problems, but once again, going back up to 65 or 70mph the trailer would start shaking side to side, and rock the rear end of the truck back and forth.

Any ideas why?

 

[steelsoldiers]

Was it loaded or unloaded at the time? Most of the incidents involving violent trailer wagging that I have seen, experienced or read about were because there was too much weight behind the axle center-line making the tongue weight too low.

 

[acetomatoco]

more tongue weight needed and lower speeds..as of course the trailer was designed for 40 mph convoys.

 

[Sarge]

I had exactly the same problem in 1995. I was driving through Wales (on my way from Ireland to Cornwall) towing an M416 with a Wrangler Jeep. Everything was fine until 80mph. Then the trailer started to sway violently from side to side. It was so violent that the back tires on the Jeep were dragged several inches left and right. After stopping and removing the seat cushion from my posterior, I repacked the trailer, moving all of the heavy books to the front. The trip resumed at speeds of up to 90mph with no further trouble. I assume that the lack of tongue weight caused the problem. Now, whenever I load a trailer, I am very cautious about tongue weight. A rough rule of thumb is; If you can lift the tongue with one arm, it's too light. That goes for small trailers. Also take into consideration whether you weigh 100 pounds soaking wet, or, like me, are a well-fed farm boy. I weigh around 250, and yes, I can pick up an M416. Or could, before I lost my back. Actually, perhaps those two things are connected. I have since towed my 416 across 49 states and had no further problems.
If you are towing a much heavier trailer, then the same rules apply, however you may want to invest in some scales to be on the safe side. I use two normal 300 pound bathroom scales with a 4x4 across them. Add up the totals and you can accurately adjust your tongue weight to 600 pounds.
Of course, the previous post said exactly the same thing in one sentence and was far better than my post. I admit that I sometimes write to entertain. Right now my pills are wearing off and I feel my verbosity decreasing....
I'll shut up now.

 

[Recovry4x4]

I'll shut up now

Nonsense John, it's always a pleasure to hear from you! God Bless my brother!

 

[maddawg308]

Thanks for all the good answers. Makes sense, I think when it happened both times, it was light on the tongue.