I think I solved Porpoising Problem
Being new to towing a TT ( hadna 5th wheel), the porpoising of my GMC HD 2500 was driving me crazy. Trailer weighs 8000 pounds and with the WDH set up by the dealer, the whole rig rode like crap. It ...
Forum Discussion
skipnchar wrote:
It would SEEM like your spring bars on your WD hitch are likely the culprit. With spring bars not stout enough to handle your tongue weight, porpoising is the most common effect. Spring bars should be sized for a MINIMUM of the actual weight of your fully loaded trailer. If you don't have weights for the loaded tongue weight (not the empty weight on the brochure) then use 15% of the GVWR of the trailer. When the size is right and the adjustment is right you should experience ZERO porpoising without air bags or helper springs.
Good luck / Skip
Here is my 7700 lb. trailer with 1000 lb. spring bars.
The only places where I have any porpoising are on certain streets in Kenosha and Brown counties in Wisconsin. Due to the way those roads were constructed I get porpoising without the trailer at any speed above 15 MPH.
