Bczoom,</P>
You are right, silicone sealant isn't affected by diesel ! But there would be only one silicone sealant to use. That GE brand, and make sure it is the CLEAR type. I use this in my sign business also,just about everyday, and clear will hold where the white does not perform and will not last as long. Don't get the Red Devil brand either, it is not worth **** . GE brand, Clear, is the only thing I would use on any application. Go ahead and purchase a big tube, like goes into a chalking gun, cost is about 4.00, you get so much more in that tube for your money, small squezze tubes, about the size of toothpaste tube, will cost you about the same, so go ahead a get the big tube. Wal-Mart & most of your hardware stores sell it. Just a extra note, before you apply any type of sealant to anything, clean the area REALLY good, several times with denatured alcohol, that way the sealant will stick to base instead of the gook or unseen film ~~~~~~~~~~</P>