Thermostat Wahler or OEM Nissan

I've had the thermostat on my M272 engine replaced by an indy mechanic. OEM was Wahler, looking at the original the the Wahler I got, the only difference was the spot where the MB logo was on the original, it was grounded out by some grinding disk on the replacement one.

After reinstalling an OEM thermostat, I am very happy to say my high temp issues have been solved!

We had to replace thermostat from Nissan group Infinity. So far no problem right now

Just make sure you buy a genuine Nissan thermostat. I don't know what it is about these cars, but they do NOT like aftermarket thermostats. Just spend the extra ten bucks on a Nissan part.

Replaced the new Mahle/Behr one with a new Wahler one, and now it runs at 97° under low load and 80° under high load, as it should, and seems to be fine.

I replaced the thermostat myself. It’s in a pretty bad place, hidden under the intake manifold. It took me about 3 hours to get the job done, had to use a mirror to see the screws. Mine was stuck open so the car in winter time wouldn’t even reach 190 F. I bought an OEM Wahler 07K121113B thermostat from Amazon for like 30$, so far has been working great.

I installed a Wahler thermostat a little over a year ago and it's still holding strong.

I had two Wahlers and they leaked as soon as I fitted them. In exactly the way you described.

I got the wahler one in 2019, that would explain the really slow leak I have.

My Wahler thermostat starts to leak after 4 years. It's not a big leak (only a cup a month) but I'd swap it asap.