bmeaggie
Member
You can see the two relays here. 25 = high ; 28 = low
https://www.autogenius.info/ford-mustang-2005-2009-fuse-box-diagram/
https://www.autogenius.info/ford-mustang-2005-2009-fuse-box-diagram/
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So to make sure... have you overheated the car, opened the hood without shutting off the engine, and made sure you can still activate the fan by turning on the AC?
If “yes” to that for certain... There are TWO fan relays... a high speed and a low speed (1 & 2). I think the high speed = ac activated. Maybe your low speed relay is bad?
No the car didn't overheat but when I got to my destination I popped the hood to verify the fan was still going. Car was at normal operating temp which is a hair below most as I have an electric pump. when I cut the ac the fan turns off. Now, I'm not sure where I have the low and high fans to kick on and off, but I would think the low speed fan would be on at normal operating temp. I just don't have a whole lot of time at the moment but I will. Good point that the low speed relay might be out, but wouldn't the high kick on a a certain temp and prevent the overheating?
A friend of mine here in the UK just had his GT500 overheat, diagnoses was the low speed fan relay stopped working which in turn prevented the hgh speed relay from workingGood point about the 2 relays.
I also see that you still have the AC system in place. are the fins on the condenser bent and restricting air flow? I know on my DD (rsx) that when I have the front bumper off again (to install new headlights) I will comb the fins on the condenser as the ones exposed thru the bumper are pretty beat up. I know my GT could use the same treatment when I have the bumper off again. I have a set of fin combs I got off the zon for less than 10 bucks. might not be the issue but a better flowing condenser would help engine cooling and AC performance. also, how are the coolant tank caps? if they are old they might not let the system come up to pressure and keep things cool, just another thought. good luck
It’s hard to prove cause without inducing the failure mode. You need to catch it in the act so to speak.
You can easily rule out the relay by swapping the two of them, turning on your AC, and making sure the fan comes on regardless which one is in pos 25 and which is in pos 28.
If those are good, I’d bet money your fan motor is starting to go out.
Next time you see temp gauge go past 1/2 and trending upwards, pull over, leave car running, pop the hood, verify fan does NOT run with and without AC on, pop off the fuse box cover and carefully feel those two relays. If they are hot as hell (like too hot to touch), you have what I had, and swapping fan out was the only thing that fixed mine. You gotta do all that kind of quickly because what happens next is a big steamy mess.
No clue about the GT500 fan being any different. All I can say is the V6 fan keeps the coyote cool just fine. So I vote OEM. I have a feeling they are the same damn thing. lol Any CFM numbers on any of them?
Stock GT fan has 6 blades and the GT500 has 7. not sure what year they changed the design so I would go with a 13'-14 GT500 fan. I think I looked on rockauto a while back and verified they were actually different. not sure about the motor itself if it is different than the stock GT one. 14' GT500 fan assembly DR3Z-8C607-C, 05' GT and up DR3Z-8C607-D
Another stocker is fine, but the general consensus in the tuning community is the Ford ‘13-‘14 GT500 fan is the best plug n play offered for s197 mustangs. They mount exactly the same on the stock radiator. You can do either and be good... just don’t get some aftermarket one that only has 1 speed.Well I think I'm just going to get a stocker from my local Ford dealer. I know it's going to be twice as expensive but I kinda gotta get her fixed up quickly as she is my daily and I currently don't have a back up ride that's on all four wheels. I can get a cheap Dorman replacement but I think I'm going oem.
I just remembered Levittown Ford.Boss, i had the same problem as you a few years ago, we have the same cars. I got this radiator M-8C607-MSVT for about $200.00 from a Ford dealer out west, can't remember the name, no more overheating.3,286 cfm, 7 blades. Just remove old one, install new one,one hour.
Yep... that’s the ‘13-‘14 GT500 fan. Really is the best one for our cars from what I understand.Boss, i had the same problem as you a few years ago, we have the same cars. I got this radiator M-8C607-MSVT for about $200.00 from a Ford dealer out west, can't remember the name, no more overheating.3,286 cfm, 7 blades. Just remove old one, install new one,one hour.
Boss, i had the same problem as you a few years ago, we have the same cars. I got this radiator M-8C607-MSVT for about $200.00 from a Ford dealer out west, can't remember the name, no more overheating.3,286 cfm, 7 blades. Just remove old one, install new one,one hour.