The trailer I bought came with an Eaz lift. It came with 500# bars. How do you size the bars? Gross trailer weight is 7,000# and 23' in length.

If I'm not mistaken it based off the actual hitch weight at the tongue. So typically a 7,000 pound trailer would have 10-12% in tongue weight so 700-840 pounds on the tongue.

 

http://auto.howstuffworks.com/auto-parts/towing/equipment/hitches/towing-weight-distribution-systems.htm

Yes, it's all about tongue weight (hitch weight).  When I worked for a boat / trailer dealer, on of my jobs was to set up trailers for the boat (load).  Once the boat was positioned, we'd put a scale under the tongue.  If the weight was off, we'd loosen the U bolts & move the axle assemblies forward & backward. 

Now, with other trailers, the axles are pretty much not moveable but the loads are...   With a stock trailer, I had trouble with a light tongue weight with 2 horses in the rear.  I added weight to the front.  With camping gear in the front, I didn't need the ballast weight.

My present toy hauler the axles are quite a bit closer to the rear...  1/3 - 2/3.  I think I am over the cap of the weight distributing hitch bars because my 300# mobility scooter is less than the weight of 3 ATVs that there is tie downs for...  plus internal cabinetry has been gutted from the rear.  So I am tongue heavy.  I don't really like WD hitches.  I we have added ballast to the rear, re-arranged the load...  need more.  

 

Now, the amount of tongue weight your truck can handle depends on the tow vehicle...  so trailer mfg really don't know what will be used.  You might not need the WD hitch bars with a real truck to tow with...  or if you pack differently.     

Yep all about tongue weight, and many TT floorplans push the 15% TW upper "limit". I would get 1000# bars for that trailer.

When set up properly they are a big benefit. I have a set for my tilt trailer and it makes a significant difference when loaded heavy.

So when the bars label says 550# is that one bar or for the set? When you recommend 1000# is that 2 500 bars or two 1000 bars?

I do notice that the ride is better with the bars. Especially bounce.

Edited July 14, 201411 yr by joecool911

My 1200# bars state 1200# on the bars, so 600 each. I would assume that 550# bars are for 550# total TW. I haven't ever heard of bars being rated individually.

 

The porpoising is much better with a properly setup WDH.

My 1200# bars state 1200# on the bars, so 600 each. I would assume that 550# bars are for 550# total TW. I haven't ever heard of bars being rated individually.

 

The porpoising is much better with a properly setup WDH.

 

It really does make a difference. I would consider going out first and weighting the truck and trailer and then get the proper bars for said weight. You can figure tongue weight from truck alone (rear axle weight) and truck and trailer (truck rear axle weight) just subtract the two and you should get the tongue weight.