Thermostat Mahle or AISIN

I still changed my thermostat to an Aisin unit for peace of mind, so far so good.

I just bought two thermostat related parts off rockauto that are both Aisin yesterday.

I have installed them in two rebuilt, and they are working perfectly fine

It's a very easy thermostat to replace, I just did it a couple days ago on a 2008 Hyundai Sante Fe with the big 3.3l V6. The gasket comes with the OE Aisin thermostat, too, making it even easier.

MAHLE was the last thermostat put in her… no issues happened since then to this day, continues to runs fine, no fluctuations in gauge, or overheating. The dealership even started to have that issue with other customers until we switch to Mahle, solve all thermostat issues.

Swapped to mahle and it's good to go.

I’ve been using Germany-made Mahle thermostat for years. Now it throws a code that the heater doesn’t work (so it won’t open electrically, but mechanically it is working just fine), but no leaks.

The Mahle thermostat arrived today along with all the other bits I think I need to put the car back together. The problem is that the new one doesn't quite match the old one.

I have the same one in my E53 X5 3.0 and it takes forever in the winter to warm up. I replaced the old one as it was leaking but the new one takes like 10miles to get fully up to temp. If I have a long coast up to a stop the temp gauge will actually go back down.

I just be replaced mine for the low regulating temperature, and the snag seemed to improve, but it will still pop up and the car is slow to hit temp, slower than it was last winter at least.