Optimum Red

This stuff always works great !

Used to seal exhaust manifold gasket on tractor. Several months with no leakage. If using on manifolds, just put a thin bead on both sides of gasket, just around the ports. Also used to seal exhaust studs on tractor that penetrated coolant jacket. No coolant leaks.

This stuff is great. You must follow the instructions though. Don’t just apply and go.

Haven't used the caulk gun size tube yet but I've used the same product from a squeeze tube size container and I'm very pleased with the performance. I've used it on exhaust system welds to inhibit rust and on a John Deere tractor that was leaking from the oil pan gasket. Just applied it externally without removing the oil pan and surprisingly it stopped the leak and saved me from removing the engine. Two months later and not a drop of oil has leaked out. So happy. Great sealing agent.

i think works great gave it 4 starts because when rolling it up to squeeze out it popped a hole in it, just threw the rest of the tube away

Awsome stuff for fixing kamado joe gaskets ! Can't ever seem to find it locally.

Really good stuff

Good gasket sealant

I recently used the Permatex 27038 Optimum Red RTV Silicone to install my intake manifold, and I’m incredibly impressed with its performance! This silicone sealant was very simple to use, applying smoothly and evenly without any mess. It formed a strong, reliable seal that held up perfectly under high temperatures and pressure, ensuring my intake manifold installation was rock-solid. The product lived up to its promises, providing excellent adhesion and durability. I highly recommend this RTV silicone for any automotive sealing needs!

All good 👍