I am not a fan of flushing any fluid. Drain and fill is what I would suggest. I also stay away from any sort of additive/flush agent.

Coolant is climbing up in price, but if you dont have any problems with the thermostat, wait till it gives you trouble, Based on its construction, typical problem is that stays partially to totally open. Worst is you replace coolant and in few months the thermostat goes bad and you have to drain again.

Nothing wrong with being proactive, but DIYers need to know what not to overdo. Basically enjoy the ride.

Salim

 

I would not change the thermostat in this case. I'm all for preventative maintenance and killing 2 birds with 1 stone. But in this case, if you had to change the thermostat even 1 day after the coolant flush, you're only losing maybe $50 worth of coolant in the worst case. Or you could just consider it another coolant drain and fill, which is good for the engine and water pump anyway. Very little incentive to spend the extra time and effort, risking the new part being defective (I find parts from the factory tend to be higher quality than what I can buy and have had mechanics echo this sentiment), and all for just a little bit of savings.

Also, not sure if this applies to you but some people in hot areas want to change the tstat to something that runs cooler, for peace of mind. These engines already run pretty cool, I think they're a 180 tstat (my coolant temp stays around 184-186 on Torque app), so nothing to be gained there.

Noticed you didn't mention a brake fluid replacement. You might look into that being in Texas. Unfortunately, it requires Techstream to work the ABS valves to do it "right." I'll stay away from my usual advice of sucking out the reservoir and just replacing that fluid...since folks on here seem very "bring it to the dealer and do it right! Dealer is always right!"

 

 

I'm in the camp that says to do ONLY what the owner's manual says to do. They know the engine design, they have the experience of looking at failure points of millions of cars. Auto shops live or die on volume, and many (hopefully not most) of them will aggressively offer services that don't accomplish much other than to transfer money from your account to theirs.

I can remember instances of car shops pushing "flush" services onto little grey-haired ladies who didn't know a thing about cars. Caveat Emptor.

 

The thermostat is one of those items that very rarely ever get a mention on this forum. I'm all for proactive maintenance but I personally think it's not an item that needs to be proactively replaced.

 

It is amazing how individual experience impacts our perspective. For me the thermostat issues have been constant open. Having 2 would increase the chance of failure.

Salim

 

Because they build cars based off MY experience with thermostats, NOT yours! I agree with Salim, they fail open.

My experience with tires is that they ALWAYS fail in no-pressure mode. You can buy a truck with dual rear wheels to help you get where you need, and yet you did not spend the money to do so. Failed thermostats are an annoyance but failed tires can mean death, and yet you did not spend the measely $3000 extra to buy a Dual Rear Wheel pickup like me. Do you even care about your family?
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Having just one fail open on a -20 degree winter day means you will NEVER have heat inside the car. Not having heat at -20 degrees means almost certain death.

And what if they both failed? Why would you ask for just two? Statistically, you have the best safety:cost ratio when you ask for 17 in parallel. Some study I read from MIT proved it.

Again, do you even care about safety?

​​​​/Sarcasm (just in case everybody missed it)
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Your parallel idea is an interesting one but I think you'd agree it would be very useful only if the failure mode were "closed." The only two times in my driving life a thermostat failed it was stuck in the "open" position, and in that failure mode having a parallel working thermostat wouldn't help. Still, an interesting concept.

 

I'd leave the t-stat alone. Not saying that OEM t-stats can't fail, but it is a rare issue with cars that are serviced with a normal coolant exchange interval. It is simple enough to monitor your coolant water temp, once you are warmed up. Exceeded temperature threshold will be more observable during longer extended drives for a failed closed thermostat. Failed open situations are more apparent if you happen to be in a region that experiences below freezing temps, warm up time will be very long and mpg will suffer.