How to Determine Trailer Tongue Weight for Weight Distribution Hitch

Question

Question:

I have a similar question regarding porpoising. We are pulling a travel trailer with GVWR of 7800, but it scaled out at 5820 fully loaded. We are using a Blue Ox TrackPro weight distribution hitch with 800 - 1200 pound bars. We experience horrible porpoising on some roads. I was not aware that too little weight in the nose of the trailer contributed to porpoising, but I'm not sure how to determine hitch weight on a travel trailer without a hitch scale. We are also looking at air bags or Timbren springs. We are pulling with a 2011 Toyota Tundra. Any assistance is greatly appreciated!

asked by: Brian H

0

Expert Reply:

An improperly loaded trailer can definitely contribute to porpoising. Tongue weight on your travel trailer should be 10-15% of the loaded trailer weight. You can find this by picking up a scale like # e99044 or you can use one of the other methods outlined in the article I attached below.

If your trailer fully loaded weighs 5,820 lbs you should have 582-873 lbs of tongue weight. If your trailer is always sitting at that weight and you're at the low end closer to 582 lbs I would say the bars are rated too high and you should swap them out for # BLU25FR rated for 600-800 lbs. If the system is too rigid it can lead to a bumpy ride which could be adding to the porpoising. However, I would get that tongue weight measured before making any changes.

Air bags are often used to help combat this and will also keep you level and absorb road shock. I wouldn't get the Timbren since they typically result in poor unloaded ride quality and might actually make the porpoising worse since they're pretty rigid. Air bags are fully adjustable so you can get the perfect setup for your trailer and WDH. You can also run them at the minimum psi when you're not towing or hauling so they won't impact ride quality.

Firestone makes the best air bags so I recommend the # F2445 for your 2011 Tundra. If you want to be able to adjust them no matter where you go from the cab of your truck you can add the Firestone Air Command # F2610. If you would rather have something you can install and forget about like the Timbren then I would at say SumoSprings like # SSR-610-47 are the better choice.