Spring Bar Tension is Higher on One Side of Trailer than Other Side with Curt Weight Distribution

Question:

I have a 25foot Heartland Prowler 25LX travel trailer with a GVWR of 6900#. Originally I towed this with a 2009 suburban using the above mentioned WD hitch. Spring bars worked fine on it. Over the winter I upgraded to a 2015 Silverado 2500 6.0L which has the 2.5inch receiver. I ordered the Curt 2.5inch shank and rebuilt the WD hitch with that shank. I had to use the last to holes with the shank in the downward position. I ended up with 7 washers which provides a pretty good tilted down position. When hooking up to my new truck, my drivers side spring bar has no tension on it with the minimum 5 chain link separation. The bars are angled upwards a bit, but no binding occurs. The passenger side spring bar with the same amount of chains is under full tension. I placed a level on my truck while on level ground and it showed perfectly level side to side, as did the trailer. When I placed the level on the top of the shank, it showed it off by about a bubbles length. The shank does seem to have a tad bit of give inside the receiver of the truck but I dont feel like that slight change would cause it go from no tension to full tension. My follow up question is what is the max number of washers you can put in this setup for the tilt as I am already at 7? All that aside I towed the trailer with it setup like that in windy conditions and it was perfectly fine. Minimal sway and a nice ride. So I guess it doesnt really matter, Im just the type of person who wants to know why something isnt working right. Thanks guys!

asked by: Aaron

Expert Reply:

The tension on the spring bars fore any weight distribution system should be nearly identical (when sitting still on level ground with the trailer in a straight line behind the truck). The little bit of play making the shank off-level at the hitch is going to translate to anything else connected down the line to be off even more so that could have something to do with it.

Curt does not specify a maximum or minimum amount of washers but if you are angling the head down to get the trailer level then that also angles the spring bars down and you might find that you need to use fewer chain links to get the proper tension on the spring bars. the heads now use long and short rods for head angle adjustment, # 17312.

If the Curt 2-1/2 inch shank does not provide enough drop on its own then you can use a different brand such as # EQ90-02-4900 which offers up to 6 inches of drop. You can also check where the spring bar attaches to the head of the system. If the one side is more worn than the other then that could be partially why this is happening. But if it is worn that much then you would want to replace the head with # C17307, for example, for trunnion bars or # C17075 for round bars on the Curt MV systems.

expert reply by: Michael H