I think you might find the cost of the Toyota fluid a little higher than expected. You can also get the silicone from a hobby shop.

I am also having a very difficult time understanding how the fan clutch is causing your overheating issue on the highway?

Idling is one thing, but moving @ 60mph provides more airflow than any 16" fan will ever throw out.

removing the bellypan is a more inviting option than rebuilding the fan clutch.

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