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  • Do we need to change that Long Life Coolant anyway?
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Do we need to change that Long Life Coolant anyway?

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 #379312  by In-trepid
 June 12th, 2019, 5:34 pm
Today I went to the Chrysler dealer to get a new thermostat. In the past some items are just better to use OEM parts and thermostats fell into that category. I'm not going to tell you how much I paid, but yeah, they saw a sucker coming. Here is the problem that I have. When comparing an old thermostat 04792699AA, which is the original part number called out with the new superseded by part number 68027789AA, I am very depressed. First, they don't even look the same and second, it is obvious that the new thermostat doesn't have the same surface area or flow capacity. Third, the spring looks much less sturdy as compared to the old part number. In fact, the new thermostat looks very similar to any cheap aftermarket thermostat. Next up was the boil test. Good results here. The new thermostat opened right on time at about 180 degrees F. The old, about 194 degrees F. Once they were open it was obvious that they will flow roughly the same. The new thermostat closed much slower than the old one once out of the hot water.