I am new to the RV world. I just bought a 2014 Sunseeker 2860DS with an air bag suspension system. I went to two different gas stations (two different air hoses) trying to inflate the air bags and could not get air to flow into the air bags. The valve on the RV appeared to be too small in diameter or the valve stem was too short for the air hose connection. Air flowed from the pump but only leaked air around the valve without inflating the air bags. Is there supposed to be some sort of adapter for the valve?
Tighten the nut around the valve and it should extend enough. I agree, these stems are WAY too short and I had the same problem as you. I bought he attached pump that latches on the valve and works well. I pulled the wheel covers and added air to the tires yesterday as well.
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2016 Forest River Sunseeker 3100SS