What Thermostat have you had good luck with?

[Wild one]

Looked down today and my coolant was running 220+ and my oil at almost 230 running 80mph with it 95F outside. I purchased a JET 180 stat last march so I’m usually running at 188F on my coolant and around 200F on my oil. My coolant level was fine and my efan is still turning. I hoping it’s just my stat. I don’t know if it gets too cold in NE OK for a restrictor plate so I guess I’ll try my luck with an ultra stat. Crazy to think that a +40$ stat didn’t last a year and a half.

Welcome to the world of thermostats now.Jets are made by motorad,and have a crappy rep,i'm amazed you got a year and half out of it. My local truck/4X4 shop quit selling them a few years ago,because of all the returns they had on the Jet thermostats.I went through 2 in less then 2 months,and you couldn't give me a Jet thermostat now

 

[WillyBo55]

I went ahead and ordered the 797 restrictor plate for ***** and gigs. And Rock auto says they have 5416 ultra stats in stock for the cheap. Couldn’t find them in stock on Amzn.

 

[Lyle Longboat]

Is it the Ultrastat 180? How long have you been running it?

It’s been ran for 4 years now and it’s the ultrastat 180.

 

[TC]

Installed the middle plate with ID - 0.75"

Also installed this ASi all aluminum radiator found on ebay, similar to one used by @aszumilo in his 4 row radiator upgrade, only one row. Fit was spot on with one exception. Bracket for lower transmission lines did not match up exactly, so I used two SS zip ties to secure. Other than that, seems to be moderate to high quality, even with the made in Asia sticker.

Bleeding air the cooling system was a no brainer due to the design of the plate. Just fill, squeeze hoses, repeat, sit overnight top it off. First drive was about 8 miles round trip 50-55 mph to get everything up to operating temp abnd check for leaks. Happy to report, no leaks, and max coolant temp was 185 degrees and held steady.
Allowed to sit for 5 hours, removed radiator cap, added 200 mL and was full again.

Took the truck on a fairly long run to to the airport and back home 5-7 pm, 96 degrees F ambient temps, 120 mile round trip with AC on the entire trip. Max coolant temp hit 190 emtpy on the way to the airport (50 minutes at 75-80 avg mph). Coolant temps hit 195 degrees F and remained steady on the trip home, loaded with five adults and luggage for four (three being female so probably within 100 lbs payload limit).

This morning, added 100 mL and it was topped off. I hope to cast a vote for restrictor plate in your poll but need to give it another week or few. I hope this restrictor plate remains in the water pump indefinetly.

Will report back if anything changes.

 

[Hemi395]

Installed the middle plate with ID - 0.75"
View attachment 571465
Also installed this ASi all aluminum radiator found on ebay, similar to one used by @aszumilo in his 4 row radiator upgrade, only one row. Fit was spot on with one exception. Bracket for lower transmission lines did not match up exactly, so I used two SS zip ties to secure. Other than that, seems to be moderate to high quality, even with the made in Asia sticker.
View attachment 571466
Bleeding air the cooling system was a no brainer due to the design of the plate. Just fill, squeeze hoses, repeat, sit overnight top it off. First drive was about 8 miles round trip 50-55 mph to get everything up to operating temp abnd check for leaks. Happy to report, no leaks, and max coolant temp was 185 degrees and held steady.
Allowed to sit for 5 hours, removed radiator cap, added 200 mL and was full again.
View attachment 571467
Took the truck on a fairly long run to to the airport and back home 5-7 pm, 96 degrees F ambient temps, 120 mile round trip with AC on the entire trip. Max coolant temp hit 190 emtpy on the way to the airport (50 minutes at 75-80 avg mph). Coolant temps hit 195 degrees F and remained steady on the trip home, loaded with five adults and luggage for four (three being female so probably within 100 lbs payload limit).View attachment 571470

This morning, added 100 mL and it was topped off. I hope to cast a vote for restrictor plate in your poll but need to give it another week or few. I hope this restrictor plate remains in the water pump indefinetly.

Will report back if anything changes.

Thanks or the info! Seems like they work pretty well and keep the truck right at the cooling system median temp or 185ish.

Did it take a while to get to 185? When I tried the smaller restrictor plate I had to really get on it to get the temp to get to 185 and it was 75 out. Other than that once it was at operating temp it worked great.

And yeah bleeding the system was a breeze with that reatrictor plate

 

[Pull Ya]

I've had a Mr Gasket 160 for a couple years with an electric fan and no shutters. Mine runs 186 all year round in town and on the highway.
Jay

 

[hemihustlin]

ive been doing some research lately after following this thread since it started. i too would like to install a 180 to 190 tstat but would like to avoid unnecessary rechanging because of defective parts. the most easily available brand through the shop where i work (where i could return as many pieces as i want no questions asked) is motorad. the parts house has all of the lines of motorad and the different temperatures et cetra in stock. i was pretty decided to go that route because as i learned here almost all tstats are made by them anyways and quality is pretty hit or miss every where so why not

then i thought wait mopar must make different temp tstats for the various applications of hemi?
this is the first one i found



seems pretty interesting. 195 a bit high but still better than 203
whats the general consensus for quality on these mopar tstats? any other lower temp models from mopar?

 

[Wild one]

ive been doing some research lately after following this thread since it started. i too would like to install a 180 to 190 tstat but would like to avoid unnecessary rechanging because of defective parts. the most easily available brand through the shop where i work (where i could return as many pieces as i want no questions asked) is motorad. the parts house has all of the lines of motorad and the different temperatures et cetra in stock. i was pretty decided to go that route because as i learned here almost all tstats are made by them anyways and quality is pretty hit or miss every where so why not

then i thought wait mopar must make different temp tstats for the various applications of hemi?
this is the first one i found

View attachment 571902View attachment 571903

seems pretty interesting. 195 a bit high but still better than 203
whats the general consensus for quality on these mopar tstats? any other lower temp models from mopar?

They also have a 180,but it's usually only available through Mopars Direct Connection dealers,and i'm not so sure they're any better then any other thermostat.My buddy had 2 of the dealer 180's fail closed in very short order,so he's one of the guys that went to a thermostat delete on both cars.

 

[Hemi395]

ive been doing some research lately after following this thread since it started. i too would like to install a 180 to 190 tstat but would like to avoid unnecessary rechanging because of defective parts. the most easily available brand through the shop where i work (where i could return as many pieces as i want no questions asked) is motorad. the parts house has all of the lines of motorad and the different temperatures et cetra in stock. i was pretty decided to go that route because as i learned here almost all tstats are made by them anyways and quality is pretty hit or miss every where so why not

then i thought wait mopar must make different temp tstats for the various applications of hemi?
this is the first one i found

View attachment 571902View attachment 571903

seems pretty interesting. 195 a bit high but still better than 203
whats the general consensus for quality on these mopar tstats? any other lower temp models from mopar?

That part number is for the Mopar 203 thermostat. All the Mopar parts sites list it as a 195 thermostat for some reason but it is indeed a 203 thermostat. If you can zoom in on the pics you'll see its stamped with "203"

 

[hemihustlin]

That part number is for the Mopar 203 thermostat. All the Mopar parts sites list it as a 195 thermostat for some reason but it is indeed a 203 thermostat. If you can zoom in on the pics you'll see its stamped with "203"

no way! no i didn't zoom in when i saw the specs marked as 195 on more than 1 site i took that as confirmation

thank you for this info!
i was sure that they must run a cooler tstat on the 6.4 srt and the like but thats interesting for sure

so in between the ultrastat 180 and the calorstat 180 (looks like its available at napa around here) what do you guys think would be the better buy?

 

[Hemi395]

no way! no i didn't zoom in when i saw the specs marked as 195 on more than 1 site i took that as confirmation

thank you for this info!
i was sure that they must run a cooler tstat on the 6.4 srt and the like but thats interesting for sure

so in between the ultrastat 180 and the calorstat 180 (looks like its available at napa around here) what do you guys think would be the better buy?

Ha you're welcome! I thought the same thing a while back and almost bought it figuring its somewhat cooler than 203. I think that PN used to be a 195 and they just never changed the description.

I have no long term data on the Calorstat, but from what I've seen in the few months ive been running one I would go with the Calorstat.

 

[Wild one]

no way! no i didn't zoom in when i saw the specs marked as 195 on more than 1 site i took that as confirmation

thank you for this info!
i was sure that they must run a cooler tstat on the 6.4 srt and the like but thats interesting for sure

so in between the ultrastat 180 and the calorstat 180 (looks like its available at napa around here) what do you guys think would be the better buy?

Even the Hellcats come stock with a 203 t-stat. Just check whatever thermostat you buy before installing it.It's a crapshoot on whether any of them last now,some do/some don't and it doesn't really seem to matter what brand t-stat you buy

 

[EdGs]

I just ordered one of the Calorstat 192° from RockAuto with my intake valve.

With the OE 203 stat I was sometimes seeing 219° -221°. Just a little high for my liking, esp. after I hit 240° when my rad shat the bed.

If I ever get my my engine reassembled and install @caulk04's trans bypass with my new PPE pan and fluid (thank you, @JHoward), I should be golden.

 

[hemihustlin]

Even the Hellcats come stock with a 203 t-stat. Just check whatever thermostat you buy before installing it.It's a crapshoot on whether any of them last now,some do/some don't and it doesn't really seem to matter what brand t-stat you buy

yea ive got a pot and a candy thermometer somewhere
i will definitely post the results of the preinstall verification!
thanks guys!

 

[EdGs]

If I ever get my my engine reassembled and install @caulk04's trans bypass with my new PPE pan and fluid (thank you, @JHoward), I should be golden.

Just checked tracking on my order, and it's on hold, in Miami. Was supposed to be here today, hopefully it'll arrive tomorrow.

More Ed luck.....lol

 

[Hemi395]

Yeah they love these Hemi's to run hot. Unloaded with the Mopar 203 tstat my truck would fluctuate up to 212 and then back down to 204. Way too hot for just driving unloaded IMO. Thats just asking for premature failure of components all in the name of emissions/minute fuel economy gains.

IMO a 190/192 tstat is perfect for a stock or lightly modified truck. You won't have any worry of popping a thermostat rationality code and it will get hot enough to make sure you have heat in the winter/moisture evaporates from the oil.

 

[EdGs]

That part number is for the Mopar 203 thermostat. All the Mopar parts sites list it as a 195 thermostat for some reason but it is indeed a 203 thermostat. If you can zoom in on the pics you'll see its stamped with "203"

Yep, same OE part I bought a couple years back and installed when I replaced my radiator about 6 months ago.



When I tested it, it opened fully at about 208°, and thats about what I was seeing on my evic (most of the time).

When my truck was younger, I remember never seeing the temp go much over 203°.

Also, still have the original water pump at 201k miles, if that makes any difference.

 

[Hemi395]

Yep, same OE part I bought a couple years back and installed when I replaced my radiator about 6 months ago.
View attachment 571940
View attachment 571941

When I tested it, it opened fully at about 208°, and thats about what I was seeing on my evic (most of the time).

When my truck was younger, I remember never seeing the temp go much over 203°.

Also, still have the original water pump at 201k miles, if that makes any difference.

Same here, my truck would fluctuate to 206 MAX and then drop down to 200 when it was new. I would honestly be ok with that.

I think they changed it to START to open at 203 vs maintaining ~203. If you look at the PN it ends in "AI" which means its gone thru 8 revisions so who knows what they did in those 8 revisions...

 

[Hemi395]

Its also crazy to me that Hellcats are driving around at ~208 coolant temps

 

[EdGs]

Same here, my truck would fluctuate to 206 MAX and then drop down to 200 when it was new. I would honestly be ok with that.

I think they changed it to START to open at 203 vs maintaining ~203. If you look at the PN it ends in "AI" which means its gone thru 8 revisions so who knows what they did in those 8 revisions...

I cut my original tstat apart after I installed the new radiator so I could bleed it easier, then swap a new one in.

I never changed it when I replaced coolant at 108k miles.

Same part #, though. I bought my '15 in Sept. of 2017 with 28k miles on it.