I have been using "Griot's" products on our new to us last year '97. I put the sealant on about a year ago, and it is time to do it again. Our trailer had been sitting outside in PA for about three years when we picked it up, so there was a lot of grim to work through on the initial cleaning.
I have been using Griot's products on our cars for many years and have been very happy. Whatever you end up deciding to use, do not use dish type soap on the trailer. It is far to harsh, instead use an automotive type soap.
Craig and Carol
1997 34' Excella 1000
1970 27' Overlander, International
2009 Ford F150 5.4L
ProPride hitch with 1400# bars
Past President Southeastern Camping Unit (12)