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What is the Difference Between Trailer Weight Distribution System Round Bars and Trunnion Bars


I have a 2004 Chevy Tahoe and looking at purchasing Keystone travel trailer total lenght 35, with Wide Stance Axles. TW is 780lbs. What is the difference between the WD w/ Sway Control Code # RP66074 and RP66078.

Expert Reply:

The Strait-Line Weight Distribution Systems # RP66074 and # RP66088 are very similar. The difference is the type of spring bars that each kit uses. The RP66074 kit uses trunnion style bars. Trunnion bars slide into the weight distribution head from the side or back. They are considered more heavy duty and can handle trailers of greater weight than round bars.

The RP66078 kit uses round bars. The round spring bars slide up into the weight distribution head and are held in place with little clips. Round bars work great for most applications. But when trailers start to get heavier with a high tongue weight approaching 1,500 pounds, trunnion bars would be a better option.

The bars in each kit feature the cam end which is used by the dual-cam sway control. Dual-cam sway control is a proactive system that stops trailer sway before it starts. Both systems have the same tongue weight capacity rating, 600 to 1,200 pounds, and the same gross trailer weight capacity, 12,000 pounds.

Then all you would need is a properly sized ball such as # 19286 (2-5/16 inch diameter) or # A-90 (2 inch diameter).

I have included a link to the installation details for Weight Distribution and Sway Control # RP66088, which is the system that I would go with. I have also included a link to our weight distribution and sway control FAQ article for reference.

expert reply by:
Michael H

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