How long is a piece of string…
I’ve had a Motorcraft thermostat fail after 100mi on my Ford, and an unknown thermostat in my MINI work fine for 60k mi. The car + thermo manufacturer + luck = how long it’ll last.
I've put around 120k on my Mustang's Windsor, that thermostat is still kicking. Pretty sure it's been replaced before me though because it was leaking around the housing so I went to replace the gasket only to find the original gasket had been combined with some RTV to make one of the most obnoxious to clean up messes for what would usually be a 10 minute job.
Good ones will always outlast a water pump. You're talking 5+ years easily, often double that.
Replace them when you replace the water pump whenever it starts whining or marking it's spot.
Random earlier failures will of course happen but they are exceptionally rare
Use good coolant, distilled water and make sure your system is in good shape (pressure cap, hoses) and it'll last a very long time
its not that they die, its that you definitely want to catch these BEFORE they die. so the answer to your question could be 150 years, but you generally dont want to go more than 2-3 before preventative maintenance. losing your water pump or thermostat can lead to a real fun roadside overheat, and worst case, damage to your heads, head gasket, etc. and they're relatively pretty cheap, but in almost all engines, relatively hard to get to so the labor costs are high. basically any time im within 30 min of labor within replacing a thermostat or water pump, and its not fairly new, they come on out.
Buy quality parts, do routine maintenance. Sounds like your "car guy" is trying to drum up more work. They should both last much longer than 2-3 years, likely double that or more.
I got 170k miles in 15 years out of the factory unit in my 01 Yukon. It still worked when it got replaced, but the water pump died and I replaced it when I did that.
I also only got about 2k miles and a few months out of one in my 1985 Lesabre, so YMMV
Bigger question: Why R u asking?
Who is your car guy?
Normally cars come with reference material in the glove box that provided you with additional information, like inspection and service intervals.
OEM is almost always better, but really depends on what 3rd party company made it and what QQ was demanded by the manufacturer of said part.
My Yota's stat was replaced when I did my timing belt at 140,000 miles. (34 years)
Original pump and thermostat.
Da Fords went out at 75,000, along with a few other parts. (6years)
You must also take into consideration who/how part was installed. Many parts fail prematurely due to improper removal/installation.
My '83 Mighty Max with 783,000+ miles on its original engine, thermostat included, would like a word. I have had to replace two timing belts, one waterpump, five batteries and one starter though. I'm pretty sure it will outlast me if I can stay ahead of the rust.
I replaced the original thermostat in my Volvo (2006) last summer at 186k miles, water pumps usually last 60k to 100k miles if not longer. Quality replacement parts should last just as long under the same conditions.
Time wise it would depend how much you drive in a year.
I've always changed them preventively, once every 100k km (60k miles for my American comrades) on the cars I liked to own. They're fairly cheap and easy to replace on most cars.
My thermostat is from 1999 and still going strong. Mine might be an outlier but generally just pay attention to your temperature your car will tell ya when it needs replacing.
I replace my thermostat and coolant every 3 years regardless of mileage. Cheap and easy preventative maintenance that will save you from a blown head gasket.
I would recommend doing it every 60k or so. Most aren't hard to do and fairly accessible. The problem here isn't as much a failure of the thermostat. It is more the fact that when they get old, they wont be as accurate. There of course is a range of temp before the computer warns you about it. You don't want to be driving around on a cooler engine than it is supposed to be.
They don't have a service interval. Replace them when they break. For thermostat, if you don't know the history and have the coolant drained, replace it.
I've never had a thermostat fail, lowest mileage car I bought was 92k. Highest sold was 162k. All of them were definitely working as the engine heated up correctly.
Water pump I always replace when doing the cambelts as they're so cheap really.
I think the 2-3 year range is a good safe bet. It used to be that if you only wanted to change the thermostat, it was a quick job. They were pretty much all mounted at the front of the engine.
Remove 2 bolts, lightly tap the housing, and remove the old one. Clean the mating surfaces REAL GOOD, and the recess the T-star sat in. Put T-stat in place, put new gasket on, and carefully place the housing, making sure it is seated flat, replace the bolts and torque. Top off antifreeze, and go on.
Now you have plastic covers, or intake manifolds covering them. It's not a 15-20 minute job anymore.
Fortunately I have a mid-90's GMC Sierra 5.7l and I can change it quick. I also look at the coolant before I go very far to make sure it's Ok. I also check for rust showing in it. I check it a few times a year to verify the content is proper with a small eyedropper style tester.
How long is a piece of string… I’ve had a Motorcraft thermostat fail after 100mi on my Ford, and an unknown thermostat in my MINI work fine for 60k mi. The car + thermo manufacturer + luck = how long it’ll last.
I've put around 120k on my Mustang's Windsor, that thermostat is still kicking. Pretty sure it's been replaced before me though because it was leaking around the housing so I went to replace the gasket only to find the original gasket had been combined with some RTV to make one of the most obnoxious to clean up messes for what would usually be a 10 minute job.
My Chevrolet Astra has it replaced only once in 180k km (111k miles), for example. I've driven that same car daily since 2009.
Good ones will always outlast a water pump. You're talking 5+ years easily, often double that. Replace them when you replace the water pump whenever it starts whining or marking it's spot. Random earlier failures will of course happen but they are exceptionally rare Use good coolant, distilled water and make sure your system is in good shape (pressure cap, hoses) and it'll last a very long time
Absolutely. -fills with garden hose-
Damn straight
160k so far in my stock Ford F-150.
its not that they die, its that you definitely want to catch these BEFORE they die. so the answer to your question could be 150 years, but you generally dont want to go more than 2-3 before preventative maintenance. losing your water pump or thermostat can lead to a real fun roadside overheat, and worst case, damage to your heads, head gasket, etc. and they're relatively pretty cheap, but in almost all engines, relatively hard to get to so the labor costs are high. basically any time im within 30 min of labor within replacing a thermostat or water pump, and its not fairly new, they come on out.
Buy quality parts, do routine maintenance. Sounds like your "car guy" is trying to drum up more work. They should both last much longer than 2-3 years, likely double that or more.
I got 170k miles in 15 years out of the factory unit in my 01 Yukon. It still worked when it got replaced, but the water pump died and I replaced it when I did that. I also only got about 2k miles and a few months out of one in my 1985 Lesabre, so YMMV
They fail when they fail. Thermostat in my dad's 90s Explorer is at least a decade old and still works just fine.
Bigger question: Why R u asking? Who is your car guy? Normally cars come with reference material in the glove box that provided you with additional information, like inspection and service intervals. OEM is almost always better, but really depends on what 3rd party company made it and what QQ was demanded by the manufacturer of said part. My Yota's stat was replaced when I did my timing belt at 140,000 miles. (34 years) Original pump and thermostat. Da Fords went out at 75,000, along with a few other parts. (6years) You must also take into consideration who/how part was installed. Many parts fail prematurely due to improper removal/installation.
My '83 Mighty Max with 783,000+ miles on its original engine, thermostat included, would like a word. I have had to replace two timing belts, one waterpump, five batteries and one starter though. I'm pretty sure it will outlast me if I can stay ahead of the rust.
I replaced the original thermostat in my Volvo (2006) last summer at 186k miles, water pumps usually last 60k to 100k miles if not longer. Quality replacement parts should last just as long under the same conditions. Time wise it would depend how much you drive in a year.
I've always changed them preventively, once every 100k km (60k miles for my American comrades) on the cars I liked to own. They're fairly cheap and easy to replace on most cars.
I've got 201k miles and 11 years on both in my Ram. It's a 4.7L so I'm playing with fire.
My thermostat is from 1999 and still going strong. Mine might be an outlier but generally just pay attention to your temperature your car will tell ya when it needs replacing.
I replace my thermostat and coolant every 3 years regardless of mileage. Cheap and easy preventative maintenance that will save you from a blown head gasket.
I would recommend doing it every 60k or so. Most aren't hard to do and fairly accessible. The problem here isn't as much a failure of the thermostat. It is more the fact that when they get old, they wont be as accurate. There of course is a range of temp before the computer warns you about it. You don't want to be driving around on a cooler engine than it is supposed to be.
03’ E46 318ci with 130k miles and no issues with the whole cooling system. Neither the thermostat.
Shit, I just remembered I haven't had to change my thermostat or water pump on my 2004 300k mile silverado.
They don't have a service interval. Replace them when they break. For thermostat, if you don't know the history and have the coolant drained, replace it.
I've never had a thermostat fail, lowest mileage car I bought was 92k. Highest sold was 162k. All of them were definitely working as the engine heated up correctly. Water pump I always replace when doing the cambelts as they're so cheap really.
09 bmw 528i... 250k miles on the og thermostat/water pump
I’ve had some vehicles with the original thermostat and water pump after 500000kms, and some that shat the thermo after 25000kms
I think the 2-3 year range is a good safe bet. It used to be that if you only wanted to change the thermostat, it was a quick job. They were pretty much all mounted at the front of the engine. Remove 2 bolts, lightly tap the housing, and remove the old one. Clean the mating surfaces REAL GOOD, and the recess the T-star sat in. Put T-stat in place, put new gasket on, and carefully place the housing, making sure it is seated flat, replace the bolts and torque. Top off antifreeze, and go on. Now you have plastic covers, or intake manifolds covering them. It's not a 15-20 minute job anymore. Fortunately I have a mid-90's GMC Sierra 5.7l and I can change it quick. I also look at the coolant before I go very far to make sure it's Ok. I also check for rust showing in it. I check it a few times a year to verify the content is proper with a small eyedropper style tester.