[nyskg]

This is 2nd time it happened...in very cold mornings(today was 5 deg F) there was no heat in the truck...last time I drove it and it overheated on me...not sure where this is coming from...can this be related to a strawberry milkshake that I had a couple weeks ago?I flushed the system very well for good 3 hrs with hot water than a cleaner and it was pretty clean...any help would be greatly appreciated

 

[Bighorn]

Check your antifreeze percentage.
You're freezing up.

 

[Highwaylizard]

Has the system been completely burped? Sounds like either the coolant has frozen or there is a blockage. Also check the drive belt on the pump to ensure it is not slipping.

 

[UPbuilder]

Or a stuck thermostat

 

[Tundra1Dan]

2nd on air trapped (burped)

 

[Stone_Blue]

Did you open the heater valve when you flushed it?...If not, there may still be stuff that didnt get flushed out of the heater core....

When flushing, did you pull one of the heater hoses off the valve at the top of the firewall?...I usually do this, and drain and fill (using a garden hose (for filling), and some cheap 1 1/2"-2" corrugated black plastic pipe (to put the outflowing heater hose into, to drain...)), from the heater valve....Its pretty much the highest point in the system and helps remove air pockets...

Prestone makes a flush & fill kit, that has fittings you mount permanently in the hose next to the heater valve for this purpose, but when I bought one, the fittings are SAE and I couldnt get them to fit the stock heater hoses...I was crunched for time, so didnt have the chance to go get supplies to make things fit...

But I also agree with everyone, its most likely either: air trapped, gooed up thermostat or heater valve, or your coolant is too diluted.....

Are you also sure you have no leaks?....It would be kinda hard to tell with a small leak in frigid temps....

 

[UPbuilder]

The reason I said stuck thermostat is typically when there is no heat and the engine overheats it points to the thermostat as stuck. The other suggestions are valid but I would start with replacing the thermostat, especially if you didn't replace it after the milkshake. A plugged heater core for example would not give you heat but the engine would not overheat.

 

[David Webb]

I have 2005 Tundra DC & same thing happened to me this morning. -3 degrees in Western North Carolina
Started truck & let run a few minutes, got in & drove, temp gauge just started moving up.
COLD AIR FOR DEFROST & HEAT
Truck started running hot after about 6 miles, stopped truck, opened hood & tube to reservoir had came off & HOT coolant coming from radiator
Let it cool a little & removed radiator cap & much hot coolant came out of top of radiator
I went back home, then to auto store to get new coolant, radiator held about 1 1/2 gal
Started truck, let idle, to normal temp range & still no heat, radiator is hot, top hose is hot, but bottom hose is not hot & no coolant felt moving thru
I feel like thermostat is stuck closed or heater core stopped up
Do you guys agree, or is some other malfunction ?
Before this happened, coolant tested -24 degrees, but I felt like icy mist was coming out of vents, it sure was cold
David

 

[Tundra1Dan]

David yours sounds like a thermostat would be my 1st guess because of the overheating.

 

[UPbuilder]

This cold weather can cause things to fail that were marginal to begin with. Thermostats are notorious for sticking in sub zero temps.

 

[2003bajatundra4x4ac]

pull the hose going to the thermostat housing and put your favorite medium screwdriver into the opening until it bottoms out. grab a hammer and give a good whack until the screwdriver goes in an inch or so. now you just bypassed the frozen stuck thermostat. start truck and see if the overheating is eliminated and then if the heat starts flowing into the cab after a few minutes or 10....

edit: when it warms up a bit, look into replacing the thermosat.

 

[nyskg]

Turn out that my coolant is freezing...they sell this predeluted crap that most likely is deluted to much...I had some water left in the the block after flushing it and that deluted the coolant even more...bought the concentrated coolant from napa and the problem is solved...
THANKS FOR HELP GUYS!

 

[Bighorn]

No problem.
Thanks for letting us know the resolution.

 

[Amberlynn]

This is 2nd time it happened...in very cold mornings(today was 5 deg F) there was no heat in the truck...last time I drove it and it overheated on me...not sure where this is coming from...can this be related to a strawberry milkshake that I had a couple weeks ago?I flushed the system very well for good 3 hrs with hot water than a cleaner and it was pretty clean...any help would be greatly appreciated
[

I have 2005 Tundra DC & same thing happened to me this morning. -3 degrees in Western North Carolina
Started truck & let run a few minutes, got in & drove, temp gauge just started moving up.
COLD AIR FOR DEFROST & HEAT
Truck started running hot after about 6 miles, stopped truck, opened hood & tube to reservoir had came off & HOT coolant coming from radiator
Let it cool a little & removed radiator cap & much hot coolant came out of top of radiator
I went back home, then to auto store to get new coolant, radiator held about 1 1/2 gal
Started truck, let idle, to normal temp range & still no heat, radiator is hot, top hose is hot, but bottom hose is not hot & no coolant felt moving thru
I feel like thermostat is stuck closed or heater core stopped up
Do you guys agree, or is some other malfunction ?
Before this happened, coolant tested -24 degrees, but I felt like icy mist was coming out of vents, it sure was cold
David

My Toyota tundra 2006 has done the same thing but I got stuck in snow storm ran it til it stopped cause I was freezing to death in the middle of nowhere it started back up but over heated again a friend. Took the thermostat out and it ran for about 6 miles and overheated again now it won't start

 

[5 Speed]

Sounds like a few people are experiencing "the cold" that they don't normally but here is some Montana winter advice.

If you pack your radiator and engine compartment with snow you can overheat your engine. Yes when it is really cold outside you still need some airflow in the engine bay and over the radiator.​

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If your temp gauge never gets warm and your engine never warms up your thermostat is probably stuck open. While sticking open is better than sticking closed you won't have any heat and your engine will suck gas because the sensors read it as in the warm up process which will make it run rich. I always change my thermostat when changing the water pump and timing belt to help prevent this issue. Make sure it is installed the correct direction and the jiggle valve is also in the proper orientation.​

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I personally run my coolant with the lowest temp possible dilution which you can't get from the 50:50 premix but I doubt that anyone is getting that low that doesn't live where it is really cold and they know how to survive winter.​

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If your coolant freezes you will overheat your engine because it won't flow and while your radiator might be cold you will usually blow off a hose. If you keep fresh coolant in your radiator I have never seen a modern engine with any build up so flushing isn't going to do anything but running your system with just water will trash it but if it was below zero it would be frozen and this would be obvious.​

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The Tundra isn't a difficult engine to drain and fill if you drain the block in addition to draining the radiator. Finding your block drain will allow you to completely remove all coolant when adding new. Make sure your heater is on to allow that to flow out with the drain​

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After refilling it is important to make sure you have removed all the air from the system. Burping the tundra isn't that difficult but you still need to make sure you have all the air out of the system. Here is where the little jiggle valve in the thermostat can help. Close the drain valve in the radiator and the block drain valve. Fill it up, open the heater to max and after topping it off start the engine and watch the temp gauge. I recommend keeping the cap off and running the engine until it gets up to temp. You will probably notice the level drop some so top it off and close the system. Make sure your overflow is topped off too. I usually let it sit overnight and in the am give it a check. Top it off if needed and go for a drive. Always keep the heater valve wide open so all air is purged from the system. I typically park it and let it cool down and give the radiator one more check and top off.​