You'll have to call Progress Mfg. I believe with their 1,000 lb 4-way sway control models you need a new head to go up to 1,200 lbs as the bars are larger. So I'll bet it's the same with the E2.
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2001 Suburban 4x4. 6.0L, 4.10 3/4 ton **** 2005 Jayco Jay Flight 27BH **** 1986 Coleman Columbia Popup