Hey guys, I'm really thinking I have a thermostat housing leak. I'll know more tomorrow night, but if it is, I'm really thinking I should get the metal one. Thoughts? Metal HAS to be more durable, right?

You could probably buy 3 or 4 plastic ones for the same price....so if a plastic one lasted 100,000 miles...it cost you ...mine was still good after 100,000 and 10 years when the car was sold....
There comes a point when adding reliability before a false economy...a quick look or smell will let a driver know their housing is failing...

Plastic cooling system parts are a disaster. As they fail replacing them with metal makes sense to me. Ever been stranded with a coolant leak at night in the middle of nowhere? What's the price difference in terms of safety?

Not sure what you mean. Is it the saving of a few bucks ($50 or so) isn't worth it at a certain point? I think I'm at the point where I'd just rather get the metal one and be done with it. That would be worth it to me.

I have never heard of one failing suddenly....other parts, yes, but the housing usually deforms a bit... resulting in a less than perfect seal, and a telltale scent in you smell for it from the leaking coolant...just like the expansion tank....easy to catch while it's a small issue.....
Many spend $$ on a 10+ year old car with the idea of "improving reliability, and to improve the length of life....simple hard fact is the older the car, the more likely an accident or medium mechanical issue will total out the car....
Putting a metal housing on a mini might have made sense imo when it was 3 or 4 years old....if you had the intention of keeping the car for the long-term....
But putting a $$$ alternate replacement part with a 200,000 mile + payback on a car that is 10+ years old, and often had 150,000+ miles might not make sense from a economic standpoint....
If you want it to be a "better" MINI cause it your passion. Go for it...but don't justify it as a $$ saving idea....the payback, even if you had a pro install the part is not really there....
Now...a track or race car, subject to extreme heat....maybe... perhaps...but cost might be no object...
But for a daily driver...not so sure.

That right there captures what you mean. I totally get that. In between posts here I thought I'd talk to a buddy in the parts industry (supplier) and said tons are plastic, that's just how it is. I'm not too keen on the metal replacements either, given the potential low quality manufacture. I'll probably end up going with another plastic, then try real hard to keep on top of it to catch any future issue when it's small. Missed it this time.

Over the years we have thought of this, but the plastic ones are so cheap and don't have enough failures to warrant the aluminum. Plus most the issues are just the gasket. We keep both in stock:
https://www.waymotorworks.com/thermo...t-r50-r53.html

housing
https://www.waymotorworks.com/r53-th...t-housing.html

Thanks WMW. I guess you would know, I only know what I see, and that's one MINI at a time, lol

Did you find the leak location?
On my 2009 Cooper thermostat housing, after closer look, it turned out to be the o-ring on the water temperature sensor. About $5.
Very easy to get to since it is non-turbo/non-supercharger.
5 minutes to swap in a new o-ring ... was lucky the housing is still fine.
The repair was as easy as changing a light bulb (pull out retainer clip, then sensor, pop on a new o-ring).
You may want to look closely at that area first.
Ron

As many others stated, there is no reason to spend the extra on the metal housings as the plastic ones hold up just fine, and again it is almost always the thermostat gasket that is the problem.

We have seen a couple of people with problems after installing the metal housings, they don't have stops for the thermostat and will allow you to install the thermostat backwards if you don't pay attention.

Went with plastic, replaced the housing and gasket. All is good now.

Wrong gen car, wrong part, wrong motor
One hell of a way to confuse folks....
Go vendor go!! DID YOU really read the post?!NOPE
just rushing in....to have your name on EVERY thread....trying to one-up ECS.....
But waymotorworks and destroy tuned jumped in first....

Sorry I caught this one so late, but mine just started failing today so I started researching them. I found an aluminum for just $15 on RockAuto. Part #11537512733PRM
The OEM on Pelican is just $36 but heck why spend more for plastic?

How many miles on your MINI?

Its an 05 S with 40,009 miles on her

Anyone have input on the $15 thermostat housing (Aluminum) from Rock Auto?

There are a boatload of folks that have well over 100,000 miles on their original OEM plastic-body thermostats, including me. Failure of the plastic component is very rare. What normally fails are the old 'white' gaskets or the thermostat itself.

FWIW, I'd stick with the original proven design.

I bought a metal one as my thermostat was leaking. Works fine. I hate plastic in a cooling system so I'll pay a bit more to eliminate a variable.