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?????Normal Operating Temp's ??????????????

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I was curious if anyone had experience or knew of the normal operating temperatures, and extremes (high and low) for:


Upper Radiator Hose

Lower Radiator Hose

Front Transmission / Differential

Rear Differential

Brake Calipers

Brake Rotors


I'm putting together an Excel Sheet for my Rally Car and i'd like to know where each of these are so i can see where i'm running cool and where i'm running hot, where i should be looking for problems, ect...




i'll post my Excel sheet when i gather the correct temps (Low, Normal, Too Hot)

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yeah seriously... um, the water on the upper hose will always be hotter than the bottom, thats why they generally will deteriorate faster than the bottom one, under normal circumstances the temperature of our thermostat stock i belive is 195 or is it hotter... I cant remember.

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"Normal operating temp??" No such thing.. all depends on how the car is set up, how you drive it, whether your cooling system and gear oils are full or low, new or old fluids, etc...


Upper Radiator Hose: Generally around whatever your thermostat is. Too hot for a hose to handle is WAY too hot for the engine to handle.


Lower Radiator Hose: Generally slightly cooler. Should be about a 20deg. drop across the radiator, not necessarily at the hoses. More drop is better.


Front Transmission / Differential: Depends on how you drive it. Mine seems to usually run well under engine temp, and I beat the crap out of it. I also maintain it well, new fluids every 15,000 miles. Once again, cooler is better. Seals start to deteriorate immediately around 300deg.


Rear Differential: Depends on the abuse.. I've seen ONE get hot enough to melt the rubber mounting bushings, and that was due to mismatched tire sizes..I should think that after a bout of spirited driving it would be under 250degrees.


Brake Calipers: Should be kept under 300deg. due to the chance of boiling brake fluid out. This is up to the driver, and how he drives.


Brake Rotors: Are they glowing red? That's too hot. Anything less is "normal"... depending on how hard you stop, how often you stop, etc. Bear in mind brake pads start to vaporize around 600deg, depending on the compound.


As with anything, maintenance is the best thing you can do.

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