Safe Coolant temp range


New Member
Feb 27, 2020
What would the safe coolant temperature and the get it off the road ASAP temperature be for a 2000 v6 mustang I also have jba shorty headers and I put tru duel flow master 40s with a 3in tube from catalytic converters back? I haven’t been able to get my Temperature gauge to work after the engine swap so I’m going to put a aftermarket temp gauge on and would like to know what temp I should be running and what temp to not let it run at?
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Nov 5, 2014
Anything below 230, factory gauges are notoriously incorrect btw

Temp gauge sending unit should be easy to fix tho, you need to find which wire and install a factory sending unit, if your trying to use aftermarket with stock gauges its probably not going to work

When i swapped from a v6 to v8 i just swapped the v6 sending unit to the v8, all my factory gauges work like normal despite it being a windsor v8

Edit: went down and looked at it and its red with white tracer

Btw, the V6 is notorious for blowing the fan relay in the main engine fuse box in front of the strut tower driver side, middle row closest to the engine, looks like a maxi fuse except its all silvery metal, its a PTC relay, it'll conk out the coolant module under passenger side fender that feeds the fans

Check that before anything else, mine went out and it wasnt fun tracing it down to the relay
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Active Member
Sep 26, 2017
Best Mustang overheating video ever is How To Cool An Overheated Engine With Julia. YouTube video by EyeHandy
Both the above posts are correct
If the fan does not come on at all it probably needs a new CCRM and or a connector
Watch the ECT pid voltage drop as it gets hot and hotter and hotter
Seems like forever waiting for .6v
Then the fans come on and you are home free
Return to customer and explain that unless it boils over and blows the cap off it is ok
NORMAL says the gauge
It will be clear up by the A or L before the fan(s) comes on
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