I'm in the slow process of replacing the inlet manifold gaskets on my VT 3.8. Are there any recommendations, such as putting sealant on the gaskets etc? Noticed the end pieces had some black silicon on them - Is that a factory thing? I bought the car ar 80k and it is now at 200k+. Not been touched by me previously! Anything else worth replacing or doing? Noticed the valley is a pain to clean without dropping crap into the working! Just going to have to do an early oil, filter & coolant replacement. BTW, What is a good coolant to use? Been using some $20 ready mixed stuff, but have noticed some corrosion around one of the coolant ports on the manifold, so maybe it just aint good enough.