Well, my 03 trailblazer threw a Po128 last week on a 1000 mile road trip. Truck ran at like 160-180 degrees the whole time on the highway but then warmed up when I got into traffic. Anyways I'm looking for opinions on what brand of thermostat I should use. I called up our local dealership and the new thermostat is 56 bucks. I really don't wanna spend that amount of money on a stupid thermostat. Auto zone is selling them for 26 which isn't bad. My question is, is it okay to go aftermarket with a thermostat or should I go oem? Opinions appreciated, thanks guys
replacing thermostat, need opinions
- Thread starter Revans381996
- Start date
I can't say for sure what brand is better or worse. I originally had a tstat replaced with a stant and an aftermarket temperature sensor at the same time. Fast forward another year after that it went again so it was a tick below 210. My mechanic (since I don't feel like dealing with the hassle of getting that out in the driveway) stated that he has seen issues with my truck and a few others that if you use an aftermarket one it can be prone to wearing out sooner than OEM. The next one he put in was ac delco for the t-stat and temperature sensor. 0 issues since then but it has only been like 5 months or so that it has been in.
Usually people replace both the t-stat and temperature sensor at the same time since they are right there near each other. I would say to nail both of them out while you are at it. I found the second time I had the SES light the temp sensor was fine, the tstat was the issue.
Usually people replace both the t-stat and temperature sensor at the same time since they are right there near each other. I would say to nail both of them out while you are at it. I found the second time I had the SES light the temp sensor was fine, the tstat was the issue.
{tpc}
Member
- Jan 22, 2014
- 359
On occasion, when towing, I've seen the engine temps climb a bit. I used a autozone t-stat and sensor from o'reilly.
After you get it all apart, you will want to change the sensor, so plan for that. The next time I change the t-stat, I'm getting the ac-delco. That won't be right away as I have a new tow vehicle, and it was a pita to do lol. Better than paying the dealer however.
After you get it all apart, you will want to change the sensor, so plan for that. The next time I change the t-stat, I'm getting the ac-delco. That won't be right away as I have a new tow vehicle, and it was a pita to do lol. Better than paying the dealer however.
Make sure to get the special socket for the sensor. I have read many posts where others say not to change it becuase why? I changed it when I did mine and what a pita. I used aftermarket on both. You are going to need a tourque wrench to put the stat in. You can do it through the wheel well or by taking the altenator out.
It is not a simple job. (Like the ones on top of the engine)
I did the later and my hands where scratched to all hell.
It is not a simple job. (Like the ones on top of the engine)
I did the later and my hands where scratched to all hell.
CaptainKD
Member
I have been running with a Stant thermostat from Advance Auto for about a year and a half and have no issues. Temperature is right on every time, the dash gauge and my Scan Gauge.
I used a 40% coupon from RetailMeNot.com and ended up only paying $14 for the thermostat. Order online and pick in store.
I used a 40% coupon from RetailMeNot.com and ended up only paying $14 for the thermostat. Order online and pick in store.
KNBlazer
Member
- Feb 8, 2012
- 811
I always suggest AcDelco.....
just order it from RA, use a 5% discount code...
**note**
It's safer replacing the t-stat through the engine bay, rather than through the wheel well... Through the wheel well, you run an increased risk of cross threading....
just order it from RA, use a 5% discount code...
**note**
It's safer replacing the t-stat through the engine bay, rather than through the wheel well... Through the wheel well, you run an increased risk of cross threading....
{tpc}
Member
- Jan 22, 2014
- 359
+1 on the sensor socket. That will likely have to be ordered. Or you can buy a craftsman one or some other brand, 18mm I think it was, and grind a slot in it like I did.
Put it this way, once you have all the fun of getting the alternator and everything out and out of the way so you can get to the t-stat, you when then realize why some do both at the same time. As far as torquing in the T-Stat to spec, that can be a challenge as well, as I found there wasn't much room for the torque wrench I was using.
But I would suggest getting the sensor and the socket, and having it on hand. Just in case. Maybe all this will be super easy for you and no big deal if you need to replace the sensor down the road. Thats what I thought it would be for me. It was only later in the afternoon as I'm calling everyplace I know of looking for the sensor socket before I gave up and made my own. Thankfully everything went back together and nothing leaked. I found out that I really didn't want to have to go back in and replace the sensor later. lol
Put it this way, once you have all the fun of getting the alternator and everything out and out of the way so you can get to the t-stat, you when then realize why some do both at the same time
. As far as torquing in the T-Stat to spec, that can be a challenge as well, as I found there wasn't much room for the torque wrench I was using.But I would suggest getting the sensor and the socket, and having it on hand. Just in case. Maybe all this will be super easy for you and no big deal if you need to replace the sensor down the road. Thats what I thought it would be for me. It was only later in the afternoon as I'm calling everyplace I know of looking for the sensor socket before I gave up and made my own. Thankfully everything went back together and nothing leaked.
I found out that I really didn't want to have to go back in and replace the sensor later. lol
BuckeyeEvan
Member
- Apr 1, 2012
- 63
I just put in the cheapest one I could find. (around $14). I think I got it at advance auto. I hope or assume it should last longer than the OEM did (around 60k) Needle now is where it should be after I replaced one that was stuck open.
loondog33
Member
- Jun 25, 2014
- 84
You shouldn't need a special socket for sensor unless you're going to reuse the sensor you're pulling out. You can just cut the wires off the sensor and use a deep socket, I believe.
And for what it's worth I've read go ac-delco for sensor, as for thermostats, they're open game. If you have to replace the t-stat you might also what to flush cooling system to improve the life of new t-stat.
And for what it's worth I've read go ac-delco for sensor, as for thermostats, they're open game. If you have to replace the t-stat you might also what to flush cooling system to improve the life of new t-stat.
gmcman
Member
- Dec 12, 2011
- 4,656
I didn't really want to spend the $$$ for AC stat either but once you remove the alternator, make a small mess of coolant, get the sensor out, button everything up.....you won't second guess the extra $25 to not have to do it all over again.
The OE stuff is real good, aftermarket is good also, but sometimes the peace of mind is worth a few extra bucks IMO.
The OE stuff is real good, aftermarket is good also, but sometimes the peace of mind is worth a few extra bucks IMO.
Mooseman
Moderator
Look at it this way, how long have the original parts lasted? I tried a Stant, found it was running too cool so went with AC Delco and it's bang on.
I can't speak for the slotted socket as I am able to replace the sensor with a closed end wrench with my e-fans. Heck, I can replace the alternator in 15 minutes flat!
I can't speak for the slotted socket as I am able to replace the sensor with a closed end wrench with my e-fans. Heck, I can replace the alternator in 15 minutes flat!
I just used the thermostat from Advance Auto and it's done will for the past 3 years. Now if it went out again, I'm going AC Delco. I do remember the replacement was a PITA becaues it was hard to reach a certain bolt. I think it took me like 2 hours to do it. Just didn't have the right tools I guess.
Wooluf1952
Member
I also used a Stant when I changed mine, and the engine runs slightly cooler then with the the AC Delco. Next time I'll go back to an OEM t-stat. Also, the neck of the Stant was a little bit bigger and I had a bitch of a time getting the hose on it.
jsheahawk
Member
I changed my thermostat about a month ago, and I've noticed a decent increase in MPG's. I went from high 14's to low 17's. I even hit 18.5 with a tailwind on the highway!
Has anyone else experienced this?
Jared
Has anyone else experienced this?
Jared
I replaced mine before I had a code pop up. Using the torque app, I noticed I was always running, around 183º and sometimes hitting as low as 162º when getting on the throttle on the highway.jsheahawk said:
After reading through threads and seeing it was running on the cool side, I decided to change the t-stat. I think I fixed the issue early enough before experiencing any MPG loss and hopefully an cat converter damage.
I think I'm just gonna bite the bullet and buy the oem Delco thermostat from the dealer. Thanks for your opinions guys!
Mooseman
Moderator
Yeah, friends don't let friends buy parts from the stealership!
KNBlazer
Member
- Feb 8, 2012
- 811
BuckeyeEvan
Member
- Apr 1, 2012
- 63
Yup. back to 18-21MPG.jsheahawk said:
side note to other poster's reply-- I had no clue I could plug my CAT from a stuck open thermostat. ouch I hope not.
I used a Motorad 413-192 from Amazon, now listed at just under $20. The air bleed hole is under the spring rather than in the body of the t-stat like the ACdelco unit. Seems to work OK. Coolant temp runs at solid 195° unless under heavier load.
Also changed the temperature sensor as others have recommended. I bought a Harbor Freight metric deepwell set, used a hand grinder cutoff wheel and cut a slot in the 18mm socket. I recall the whole set was cheaper than the specialty socket.
I had or should say, having an ongoing issue with the sensor weeping coolant. Initially torqued to spec sensor weeped so I tightened slightly after a few months. A couple months go by and the coolant temp was running about 10° cooler. Found the sensor had broken off in the block so I replaced again but used additional Teflon pipe sealant. OK for several months but now have noticed it's weeping again. Not sure next course on sealant
Also changed the temperature sensor as others have recommended. I bought a Harbor Freight metric deepwell set, used a hand grinder cutoff wheel and cut a slot in the 18mm socket. I recall the whole set was cheaper than the specialty socket.
I had or should say, having an ongoing issue with the sensor weeping coolant. Initially torqued to spec sensor weeped so I tightened slightly after a few months. A couple months go by and the coolant temp was running about 10° cooler. Found the sensor had broken off in the block so I replaced again but used additional Teflon pipe sealant. OK for several months but now have noticed it's weeping again. Not sure next course on sealant
gmcman
Member
- Dec 12, 2011
- 4,656
I agree...if you can wait a few days then go with the AC from Amazon, $$$ saved will help you with the ECT sensor, be sure to replace both.Revans381996 said:
If you're handy, then cut a slot in a 18MM deepwell for the sensor.
Here's mine, just be sure to wear safety glasses.
If you do replace the sensor, please note that they take very little torque...don't know how much off hand but they can be stripped fairly easily so go slow and careful.
[sharedmedia=core:attachments:45396]
[sharedmedia=core:attachments:45397]
Replaced the thermostat with a oem one from the dealer. Believe it or not it only costed 13 bucks because I had 26 dollars off of my next purchase from the dealer.
