My fan definatley needs it then, it doesn't move a whole lot of air in comparison to the one on our '83, which never even reaches 83C, mine still goes to around 90C from time to time, new radiator cap helped, but my fan is loose, even with the engine hot it can be easily turned once the engine is off. It also doesn't make the hovercraft sound that I have noticed on our 83, after a little while of driving with that one or running the engine, it revs that fan up like no tomorrow and moves a TON of air.....maybe I will try to add fluid to it. Its not a huge concern right now, as the highest temp my car has ever reached was a hot day all freeway temp of about 105-110C max. never went any higher, only lower. Probably partly due to the aux fan coming on, it still functions properly and comes on around 95C or so....

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