I have always used the Dicor self leveling sealant and non leveling sealant depending on the application.
Just clean the area of the TPO roof and apply. I have been using it for 3+ years and have not had one issue. Not that I had issues in the first place, I am just anal about the RV being sealed properly and on my last RV, from the factory left little to be desired when it came to sealing the roof properly.
2017 Thor Challenger 37LX, Westward interior, Riverside paint job. Upgraded to 4 battery setup, Splendide 2100XC Washer/Dryer combo, Progressive Industries HW50 EMS, Heavy Duty Steering stabilizer, and TST TPMS 6+4 setup for tow vehicle . Member FMCA
Use a PLASTIC scraper to get the goo off, do NOT use a metal scraper, to much risk of cutting the membrane. You don't have to get every scrap of old stuff off, its soft and the new will cover what you don't remove. Do try to get as much as possible, leaving a little is ok.
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FMCA 101070S Dave & Myra One day your life will flash before your eyes,
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