I have been using BEST rubber roof cleaner.. Very easy. Handle brush it it on ..like your washing the TC...and wash it off with the hose. Roof is left white and protected foe six months. It's called B.E.S.T. Use it on the vents too.. Gently
2011 Palomino Maverick 8801, 2005 Chevy 2500HD Crew Duramax/Allison, Timbrens, Bilsteins, Michelin LTX M/S2, Hypertech programer & Honda Eu2000