Summer coolant temp?

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Normal OP Temps in all stock, in the mile high city, 100F OAT & full noon sun:

98-02 ECT 184F to 187F w/ momentary 190F reads.
03-07 ECT 194-197F w/ momentary 200F reads. OAT below ~70F ECT 184F to 187F.

AT fluid temp 145 to 165F.
 
Just got back from driving through the desert. At 114F OAT my 01 coolant ranged from 191F to 198F. During stop and go traffic, I noticed my AT temp ranged from 160's and I think I saw it go up to 187F.

At home, 70-100F OAT my coolant is around 186-191 and my tranny is 140F to 170F on random slow hill climbs at around 50mph and not enough to downshift.

These temps are with a Dissent front bumper with winch (with license plate), Dissent 3rd/filler skid, SLEE front skid and Trail Tailor creeper skid.
 
Mile High City 100 OAT, I’ll hit 205 sitting in traffic with the AC cranked and rear air on. If that happens, I’ll shift to N to get the engine RPM and fan turning faster plus turn off the AC which prevents the temp from climbing. Once I’m moving it drops back to 195. During the summer the fan clutch seems to lock up and is likely the source of my issues.

06 LX using Fusion.

Does Fusion have trans temp for all years? I can’t find it on the list.
 
Normal OP Temps in all stock, in the mile high city, 100F OAT & full noon sun:

98-02 ECT 184F to 187F w/ momentary 190F reads.
03-07 ECT 194-197F w/ momentary 200F reads. OAT below ~70F ECT 184F to 187F.

AT fluid temp 145 to 165F.
Ugh. I know you are able to get these temps on a “tuned” 98-02 which tells me anything hotter than that is unacceptable and must be addressed. 😂
 
Mile High City 100 OAT, I’ll hit 205 sitting in traffic with the AC cranked and rear air on. If that happens, I’ll shift to N to get the engine RPM and fan turning faster plus turn off the AC which prevents the temp from climbing. Once I’m moving it drops back to 195. During the summer the fan clutch seems to lock up and is likely the source of my issues.

06 LX using Fusion.

Does Fusion have trans temp for all years? I can’t find it on the list.
So running at those temperature is not necessary bad. I am not sure why people are so obsessed with being in a specific range. Even if the coolant temp touches 220 I am not sure if that's a problem. What is a problem, thats if you get these temp constantly in those ranges (215-225F range). Then there is a problem in your cooling system that needs to be addressed for sure.

This was the condition I was seeing on my car when I lost my radiator. I noticed it. Troubleshooted it to a bad radiator where I found it leaking and replaced it quickly. In my case I did a timing belt with the radiator swap. Temps back to normal 187-197...
 
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Another data reference:

From October to April in Central Texas, my coolant temps range from 185-194. Once summer hits I'm ranging 190-198 in normal driving conditions. When I am sitting in carpool at 4pm I can get up to 214 but quickly back down to ~196 when driving. I have a new radiator (installed 2020), a new fan clutch (installed 2020) with no leaks.

I do not have toyota red coolant but am using autostore Asian formula. Should I drain and refill with official toyota red coolant from the dealer? Would that matter with my anecdotal info above?
 
Another data reference:

From October to April in Central Texas, my coolant temps range from 185-194. Once summer hits I'm ranging 190-198 in normal driving conditions. When I am sitting in carpool at 4pm I can get up to 214 but quickly back down to ~196 when driving. I have a new radiator (installed 2020), a new fan clutch (installed 2020) with no leaks.

I do not have toyota red coolant but am using autostore Asian formula. Should I drain and refill with official toyota red coolant from the dealer? Would that matter with my anecdotal info above?

I am not sure if the red coolant will make such a significant difference... now sure if anyone has gone from normal coolant to red coolant on this forum.. this would be good to know if the coolant makes such a significant difference.

BTW I have 3 Toyoto's as you can see from the sig... the 2 Toyo trucks are running normal coolant (neon green) and run the same coolant temps normally i.e. between 187-200 in normal 90F temp down here in GA.. soo if anything the red coolant may reduce the temp a degree or 2.. not worth the hassle in my opinion.
 
Another data reference:

From October to April in Central Texas, my coolant temps range from 185-194. Once summer hits I'm ranging 190-198 in normal driving conditions. When I am sitting in carpool at 4pm I can get up to 214 but quickly back down to ~196 when driving. I have a new radiator (installed 2020), a new fan clutch (installed 2020) with no leaks.

I do not have toyota red coolant but am using autostore Asian formula. Should I drain and refill with official toyota red coolant from the dealer? Would that matter with my anecdotal info above?

What is the status/age/mileage of your thermostat and radiator cap? OEM or aftermarket? Those can factor into the coolant temps.

What brand radiator and fan clutch are you running?
 
What is the status/age/mileage of your thermostat and radiator cap? OEM or aftermarket? Those can factor into the coolant temps.

What brand radiator and fan clutch are you running?
The thermostat was replaced in 2020 when I had the timing belt and water pump replaced (replaced at ~250k and now I have 275k mileage). Radiator was replaced in 2020 and I believe it is the original cap but am not certain if a new one came with it. Is that typical for an original to be used or would it have come with a new cap?

All parts are either OEM from Toyota or denso/aisin.

one other thing I forgot to mention...I'm in Central Texas which means in the heat of the day we are over 100 degrees (just set a record for 4th longest streak of 65+ 100-degree days this summer). Nice cool front coming in tomorrow and the highs are going to get down to 96-97 LOLOLOLOL.
 
Another data reference:

From October to April in Central Texas, my coolant temps range from 185-194. Once summer hits I'm ranging 190-198 in normal driving conditions. When I am sitting in carpool at 4pm I can get up to 214 but quickly back down to ~196 when driving. I have a new radiator (installed 2020), a new fan clutch (installed 2020) with no leaks.
Same. The coolant temp on my 06 goes down as soon as the vehicle starts moving.

06 LX using Fusion.

Does Fusion have trans temp for all years? I can’t find it on the list.
I was able to activate the two Trans Temp PIDs on my 06 by purchasing the complete software pack from OBD Fusion.
801C24CE-B2F2-457E-866E-196C694F039B.jpeg

I also setup the parameters like for the coolant temp to change color (to Red) if it reads 200°F and higher. Pic was taken right when the light turned green and we were on idle for about 5mins or so. It goes down to 192°F - 195°F when driving. The LX has front and full underbelly aluminum armor by Dissent, also has rock sliders, rear still has the factory plastic bumper - just to give you a perspective on the additional weight and front ram air ventilation.
 
The thermostat was replaced in 2020 when I had the timing belt and water pump replaced (replaced at ~250k and now I have 275k mileage). Radiator was replaced in 2020 and I believe it is the original cap but am not certain if a new one came with it. Is that typical for an original to be used or would it have come with a new cap?

All parts are either OEM from Toyota or denso/aisin.

one other thing I forgot to mention...I'm in Central Texas which means in the heat of the day we are over 100 degrees (just set a record for 4th longest streak of 65+ 100-degree days this summer). Nice cool front coming in tomorrow and the highs are going to get down to 96-97 LOLOLOLOL.
Yes, There is that high ambient heat factor. It sounds like you have things covered and your temps seem to be ok given the heat you are dealing with. As for the radiator caps, when I bought I new OEM radiator for my 80 Series years ago it came with a new OEM radiator cap. I can't say the same is the case for the new OEM 100 Series radiator. If you are unsure, new OEM caps are cheap.
 
Same. The coolant temp on my 06 goes down as soon as the vehicle starts moving.


I was able to activate the two Trans Temp PIDs on my 06 by purchasing the complete software pack from OBD Fusion.View attachment 3089417
I also setup the parameters like for the coolant temp to change color (to Red) if it reads 200°F and higher. Pic was taken right when the light turned green and we were on idle for about 5mins or so. It goes down to 192°F - 195°F when driving. The LX has front and full underbelly aluminum armor by Dissent, also has rock sliders, rear still has the factory plastic bumper - just to give you a perspective on the additional weight and front ram air ventilation.
Do you know where in the system it is getting the both trans temp signals from?
 
Do you know where in the system it is getting the both trans temp signals from?
Good question, and my answer is I don’t know, yet. Lol. I’ll switch to desktop later to go over the component breakdown in Partsouq, I’m sure there is a sensor there that would illustrate one for the at pan and the other for the at torque converter.
 
Hi! Having read all the great info in previous posts, I have 2 somewhat related questions.

1. @Brandon Ryder mentioned the engine should not be shut off after overheating because that may destroy the engine. But I read from a Toyota dealer site that when overheated, should pull over and shut off engine immediately. Which way is more effective in avoiding engine damage?

2. When cleaning the radiator fins, do I have to wait for the engine to cool down completely to pressure wash? (If I were to use the pressure wash hose from the self-service car wash, it'd be hard to wait for engine cool down.)

Thanks!

 
Hi! Having read all the great info in previous posts, I have 2 somewhat related questions.

1. @Brandon Ryder mentioned the engine should not be shut off after overheating because that may destroy the engine. But I read from a Toyota dealer site that when overheated, should pull over and shut off engine immediately. Which way is more effective in avoiding engine damage?

2. When cleaning the radiator fins, do I have to wait for the engine to cool down completely to pressure wash? (If I were to use the pressure wash hose from the self-service car wash, it'd be hard to wait for engine cool down.)

Thanks!

To your second question: the radiator itself will cool down relatively quickly, enough that cold pressure washer water won't damage it. The engine behind it is a little different.

Pressure washing a warm engine is fine. I'd suggest not washing a hot engine. In the time that you'd get to the car wash, clean the rest of your truck, then turn to the engine, you should be fine.
 
Hi! Having read all the great info in previous posts, I have 2 somewhat related questions.

1. @Brandon Ryder mentioned the engine should not be shut off after overheating because that may destroy the engine. But I read from a Toyota dealer site that when overheated, should pull over and shut off engine immediately. Which way is more effective in avoiding engine damage?

2. When cleaning the radiator fins, do I have to wait for the engine to cool down completely to pressure wash? (If I were to use the pressure wash hose from the self-service car wash, it'd be hard to wait for engine cool down.)

Thanks!

For your first question, it depends on if you know generally why it’s overheating. If everything is fine and suddenly it overheats, or you know you blew a hose or radiator (steam), then shut it off.

If you’ve been pulling a trailer up a mountain pass at 80mph (if that was possible…) and you see the temp climb, then pull over and keep it running so it cools down, which will help prevent blowing a head gasket or warping a head.

The idea is if coolant is circulating you can recover. If not (closed thermostat, blown hose or heater T) you’ll only make things worse by continuing to run it.
 
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