I'm putting a new water pump on my '99 2500 V10, and it has the O-ring instead of a gasket. I'm new to this style and was wondering if the O-ring should go in dry or do I apply grease or something to it? And second, should I RTV the metal mating surface where a normal gasket would go, or just bolt straight up. I'm assuming the RTV wouldn't hurt at all, but just want to make sure.

 

I tend to use a bit of grease to hold o-rings in place during installation, but, I've never done a wp on a v-10....... maybe someone else here has...

 

Thanks Hey You, I just got the pump and it doesn't mount like I thought it did. The O-ring does all the sealing and there is barley any metal to metal contact surface (basically just where the bolts go through) so no need for RTV sealant.