The way to do it is to pull it apart , clean the rubber gasket real good (spread it open and wire brush it ) to get any rust / dirt out . When installing it on the new window , with the rubber in the channel, lube with a little soapy water and push onto the glass. When it dries it will grip just fine.

85' 4x4 e-cab flatbed 22r carb ((SOLD))
86' 4runner, 22re , "60 buck truck"
95' 4runner, 22re,5sd, last of the good ones
02' Tacoma prerunner, 2.7L, 5spd., 4x4