Thermostat MOPAR or Wahler

Spend slightly extra and get a quality OEM Wahler thermostat.

Gave up and bought the genuine Mopar stat, haven't had issues since.

Finally got around to replacing the thermostat on my 2000 XJ. Temp rarely hit 210 unless I was idling for a while so I suspected a bad thermostat. Sure enough it was stuck in the open position. I was able to find an OEM one part # 5202 8186AC. 195 degree with a weephole. Noticeable difference in performance and it’s nice to have heat again.

Replace stat with a Mopar 195f unit for optimal results.

Got the Wahler on my 2008/2011 and it was identical to the MB part except the area that had the MB logo on the original one was ground out.

My 2007 MKV 2.5 Jetta is still having overheat problems even after changing the tstat to a OEM (Wahler) and the waterpump to one with metal impeller, which works way better than the original.

Thermostat was ALSO replaced when the water pump was, with a Wahler unit. Guess I got 10k miles out of it?

I had a very similar issue. Radiator and Thermostat replaced after accident. 2014 WK2 3.6 V6 was overheating when I drove up the mountains in Colorado. The problem was the mechanic put a Napa thermostat in, then replaced with another napa thermostat. I bought a MOPAR thermostat and swapped it myself.

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.