I had a similar problem but my chirped and squealed.
Try changing the pigtails first. It's the least expensive solution. If only one side is making the noise, switch the pigtails an see if that stops it. If it does you only need to replace the one that's causing the noise.
2010 Rockwood Roo 23SS
2009 Ford F-150 XLT SuperCrew with Max. Towing
2011 Rockwood Signature Ultra Lite 8293SS, 12K Equal-i-zer
2016 Ford F-250 XLT SuperCrew, 6.2L, 4x4, 6'9" bed, 3.73
2010 Rockwood Roo 23SS (2012 - 2014)
2009 Ford F-150 XLT SuperCrew, 5.4L, 4x4, 5'6" bed (2012 - 2016)