Dressing a grommet

On my 1989 XJ6, I am replacing the coolant level sensor (DBC2111), and I am using a brand new rubber grommet (CAC7888). I wonder if I should use the grommet “dry”, or if I should apply the Blue RTV or something similar on both the grommet-to-sensor contact surface, as well as on grommet-to-tank contact surface. I’d appreciate your thoughts & experience.

I would think they were fitted dry at the factory so that is what I would do.

A light smear of Vaseline or rubber grease will help with installing it.

Since its rubber, its intended to be installed dry. As Robin said, a bit of Vaseline or something similar is fine, but I wouldn’t use any RTV.

Thanks for all the replies guys. I went without any dressing, but discovered that with the grommet on the sensor, it is VERY difficult to put the sensor in place. However, grommet into place in the tank, then sensor into the grommet, went fairly easily. No more coolant mess in the tray underneath!

It was a huge victory for one man, an insignificant one for a mankind.