2013 yukon denali operating temp

[Gavin mccaffrey]

So my original radiator started to leak out from a crack in the plastic, I bought a aftermarket aluminum one. If it's below 50 degrees I will sit at or right above 185 I put in new thermostat and coolant sensor and still will not get above 185. Operating temp is 210. Thought?

 

[Marky Dissod]

my original radiator started to leak out from a crack in the plastic, bought a aftermarket aluminum one.
If it's below 50F degrees it will sit at or right above 185F. put in new thermostat and coolant sensor and still will not get above 185F.
Operating temp is 210F. Thought?

Think you didn't search this forum for something similar happening very recently to someone else.
There is a 3rd smaller hose connecting the radiator to the pressurized coolant reservoir.
Choke, but do not completely close this hose with circular worm clamps. When you get it right, temp will stabilize @ 203F.
GM OE operating temp of 212F is worth 1MpG vs operating temp of 203F. Motor oil & ATF last longer @ 203F vs 212F.
Don't worry, GM measures temp where it's easy to put the temp sensor, not at the hottest spot, so H2O vapor will still boil away.

When you tow something very heavy, open the worm clamps. You now have a custom-adjustable radiator, congratulations you lucky bastaducci.

 

[mikez71]

Does the new radiator not have transmission cooler connections or?
Just because I'm suprised a radiator swap would do that..
(I shouldn't be surprised when missing restrictor that Marky D mentioned)

And wow, 1mpg from 203 to 212? I wonder if it's another 1mpg from 192 to 203?

 

[Gavin mccaffrey]

Does the new radiator not have transmission cooler connections or?
Just because I'm suprised a radiator swap would do that..

And wow, 1mpg from 203 to 212? I wonder if it's another 1mpg from 192 to 203?

It has trans cooler connections

 

[Joseph Garcia]

Welcome to the Forum from NH.

Lots of knowledgeable folks here who freely share their knowledge, experiences, and perspectives. Knowledge is power.

I hope that you will become a participating member in the Forum's discussions.

Pics of the truck, please.

You are already receiving sage advice from the knowledgeable folks on this Forum.

As @Marky Dissod stated above, the aftermarket radiator probably does not have a built-in restrictor in the nipple for the 3rd small hose going back to the reservoir. There is a recent thread on this Forum (within the last 2 weeks) that discusses this issue in great detail, and outlines several methods to resolve this issue, while still using the new aftermarket radiator.

 

[Charlie207]

So my original radiator started to leak out from a crack in the plastic, I bought a aftermarket aluminum one. If it's below 50 degrees I will sit at or right above 185 I put in new thermostat and coolant sensor and still will not get above 185. Operating temp is 210. Thought?

IIRC, there should be a regulator of sorts at the output of the nipple on the radiator to overflow tank. When I installed an all-aluminum radiator that had no restriction, my coolant temps took forever to rise, and never got close to 200F.

My solution was to take a fired .45ACP brass, and drill out the primer pocket with a .125" (1/8") drill bit, and that reduced flow enough to allow temps to rise. Click here: https://www.tahoeyukonforum.com/threads/cold-case-radiator.135572/post-1705563

 

[mikez71]

Of course, you want the proper temp reading so the ECM is happy...
But is the actual engine temp cool? Or rather the temp sensor is near the overflow, and so gets a false reading?
Restricting or opening that hose shouldn't change actual engine temps?

 

[Gavin mccaffrey]

Of course, you want the proper temp reading so the ECM is happy...
But is the actual engine temp cool? Or rather the temp sensor is near the overflow, and so gets a false reading?
Restricting or opening that hose shouldn't change actual engine temps?

Engine temp is cool, heater will be set at 90 probably actually blowing around 75-80. Temp sensor is on the opposite side of the engine so probably not getting a false reading.

 

[Gavin mccaffrey]

IIRC, there should be a regulator of sorts at the output of the nipple on the radiator to overflow tank. When I installed an all-aluminum radiator that had no restriction, my coolant temps took forever to rise, and never got close to 200F.

My solution was to take a fired .45ACP brass, and drill out the primer pocket with a .125" (1/8") drill bit, and that reduced flow enough to allow temps to rise. Click here: https://www.tahoeyukonforum.com/threads/cold-case-radiator.135572/post-1705563

Thank you! I'm guessing that's exactly what is going on ! I will get on the freeway in the morning and temp will sit right at 185 then drop to 0 or 160 and I will get the engine hot ac turned off and fans turn on

 

[Marky Dissod]

... wow, 1MpG from 203F to 212F? I wonder if it's another 1MpG from 194F to 203F?

Powertrain (that's engine AND transmission) op temps have been rising since the 70s when CAFE MpG testing became a thing.
It was noticed that - ALTHOUGH MOTOR OIL & ATF DID NOT LAST AS LONG AT HIGHER OP TEMPS - MpG improved up to about 221F.
By the way it was also noticed that motor oil & ATF pressures dropped slightly as temp rose from 176F to 221F, so if you want a lil more oil pressure, run cooler.

Of course, you want the proper temp reading so the ECM is happy ...

'Proper engine temp' is not a point, it's a range; anything over 167F is technically closed loop, it just costs MpGs because oil & ATF are thicker colder -
and thinner hotter, which is why automakers prefer the hotter side of the op temp window.

Engine temp is cool, heater will be set at 90F probably actually blowing around 75F-80F.

If the cooling system's thermostat is open, the coolant in the heatercore is hot enough to keep you hot enough, but
yes, hotter coolant does also mean hotter heat coming out the vents.

Temp sensor is on the opposite side of the engine so probably not getting a false reading.

No such thing as a 'false reading', really; between cylinders 3 & 1 is actually a clever place to put the temp sensor for several reasons.

@Gavin mccaffrey, get yself a few of those clamps that you tighten/loosen with a screwdriver, sized for that hose I mentioned above,
and tighten that hose ...

 

[Charlie207]

Of course, you want the proper temp reading so the ECM is happy...
But is the actual engine temp cool? Or rather the temp sensor is near the overflow, and so gets a false reading?
Restricting or opening that hose shouldn't change actual engine temps?

I remember reading various product websites that referenced the restrictor.

Edit: the gargler machine returned this: https://www.google.com/search?q=GM truck radiator flow restrictor

 

[Gavin mccaffrey]

Powertrain (that's engine AND transmission) op temps have been rising since the 70s when CAFE MpG testing became a thing.
It was noticed that - ALTHOUGH MOTOR OIL & ATF DID NOT LAST AS LONG AT HIGHER OP TEMPS - MpG improved up to about 221F.
By the way it was also noticed that motor oil & ATF pressures dropped slightly as temp rose from 176F to 221F, so if you want a lil more oil pressure, run cooler.
'Proper engine temp' is not a point, it's a range; anything over 167F is technically closed loop, it just costs MpGs because oil & ATF are thicker colder -
and thinner hotter, which is why automakers prefer the hotter side of the op temp window.If the cooling system's thermostat is open, the coolant in the heatercore is hot enough to keep you hot enough, but
yes, hotter coolant does also mean hotter heat coming out the vents.
No such thing as a 'false reading', really; between cylinders 3 & 1 is actually a clever place to put the temp sensor for several reasons.

@Gavin mccaffrey, get yself a few of those clamps that you tighten/loosen with a screwdriver, sized for that hose I mentioned above,
and tighten that hose ...

Will do! Appricate the help

 

[Marky Dissod]

Will do! Appreciate the help.

Just trying to come up with a simpler (though admittedly less bad@$$) solution than a spent .45ACP shell that would also give the added benefit of adjustability.

 

[Charlie207]

Just trying to come up with a simpler (though admittedly less bad@$$) solution than a spent .45ACP shell that would also give the added benefit of adjustability.

lol