Several months ago, my truck said "engine hot A/C turned off" so I replaced the thermostat. It worked for about 2 months then said the same thing so I got a new thermostat thinking it was a bad thermostat. It worked for a little bit. Ever since then, at random times, my transmission temp will go up to 200 at least ever time I drive. My truck will overheat and pour out radiator fluid. Sometimes it happens when I drive 10 minutes away and other times it's when I drive 2 hours away.. My fans come on. I've added coolant to it, checked the transmission fluid, checked the water pump, and the hoses to see if their clogged. I had it put in the shop at the dealership and explained that my trans temperature gets really high and I guess they thought I meant my coolant. They replaced the coolant thermostat sensor and I went and got it from the shop, headed home and it got up to 210. When I called them to tell them my truck still gets too hot, they say 210 is normal because they apparently don't know the difference between the coolant and trans temp. I'm tired of dealing with them and I don't know what it could be.. My truck doesn't have a trans cooler so maybe that could be it. It will sometimes get up to 240 degrees.

 

200° is totally normal for the transmission. At 270°, I'd pull 'er back and let it cool.

Are you towing?

Allan

 

Well when it gets to 230, it starts smoking and shooting out radiator fluid. Everybody I know with the same truck doesn't even hit 200. No I'm not towing

 

Sorry to hear about this, bay_baird. Would you like for us to reach out to your dealership to further explain what your specific concerns? If so, just private message us your VIN and dealership name and we can look into this for you.

Amber N.
Chevrolet Customer Care

 

nobody move

check with a turkey thermometer first - dash guages are wrong sometimes (are not precision instruments). get a pocket $25-$35 code reader. get pcm's water temp reading (likely from bi-metal sensor voltage)

after that? get a flush kit (prestone has em) if you believe it's that (save your fluid $$ in pan first)

you didn't say fan. on my truck it's a wax type (not electric). to stick at 200 it needs to be working

at 210 your not at danger level of aluminum bending (up to 275). but your near 212 boiling. but i bet your fluid is 50/50 so that should be no where near coolant boiling temp. 210 is livable but sure, keep diagnosing why

don't take crap from a dealer if it's on warrantee. definitely not!

head problems or valve problems or running rich can overheat. but you'd have other typical sympoms. bad mileage, smelly exhaust. maybe leaks, misfires, rough running / missing. missing coolant or oil, milky oil, bubble in radiator. etc.

 

i forgot to say. i assume it overflows because your putting too much in. you shouldn't get coolant spilling out at 210 deg, that's why i assumed. if you do, you have a pressure cap on your recovery bottle, you didn't mention testing that. you also didn't mention if you followed the fill procedure (see youtube) with engine running "correctly". if it's eating coolant (i mean: if you can't confirm all of the coolant is going on ground you assumed it was) and it's overheating see: "mystery coolant" issue for silverado / s10. or could be something else. check all fluids make sure they're reasonable (no funny smell or color) definitely don't run the car if you think it may cause engine damage. 210 with coolant in block should do any harm: assuming your not having other issues, like low power, stumbling hesitation etc (would indicate a diff. problem).