[Stompychann]

Hello everyone
I have a 2008 Buick Enclave cxl. It drives fine and holds normal coolant temp in town. But when I do mountain driving where I’ve been climbing in elevation it slowly starts to over heat.
my question is: Is it my water pump, thermostat or radiator? Just trying to pin point the issue instead of just changing all 3.
Thanks!!

 

[dzs3fz]

Have you checked the coolant level?

 

[Stompychann]

we

Hello everyone
I have a 2008 Buick Enclave cxl. It drives fine and holds normal coolant temp in town. But when I do mountain driving where I’ve been climbing in elevation it slowly starts to over heat.
my question is: Is it my water pump, thermostat or radiator? Just trying to pin point the issue instead of just changing all 3.
Thanks!!

 

[Stompychann]

I have not. Wouldn’t it tell me on the onboard computer if it was low?

 

[dzs3fz]

No....The radiator cap is located under the plastic shroud covering the radiator. The overflow container might also be dry.

 

[rbarrios]

the 1st thing that comes to mind is a weep hole leak/shaft leak on the water pump.
it can be slow enough that the coolant leaks on the side of the timing chain cover- but dries before it hits the ground.
slowly you end up with a cooling system thats low on coolant.

here is a thread I made- on HOW TO spot a leak from the water pump.

How to spot a water pump failure- with pic.

You can spot a slow leak by looking for signs of dexcool leaking and drying on the timing chain cover. Heres an example- note the trail of dry coolant (white residue). Another thing to look for is the signs of coolant being flung by the spinning water pump pulley. Another sign to look for...

www.enclaveforum.net

to check your radiator- do it when cold. and you have to lift the cover.
here is the cover on my Traverse.. should be similar on your Enclave

 

[rbarrios]

here is another thread.
HOW TO change your thermostat. Mine is the direct injection engine. yours is not. but the procedure should be fairly the same.

How to replace your thermostat and radiator hoses.

coolant change at 5yr/100,000 (as per the manual) I had my water pump replaced at 39,400… so the coolant was not 100% factory original. So I waited till now. About to turn 7 yrs old. Now at 111,000. Cooling system working fine….. (lets keep it that way). I have a 4,000 mile trip coming up...

www.traverseforum.com

 

[charlie123]

Just another thought. Years ago I was driving a new rental car and took it into the mountains. As soon as I was driving on the incline a warning came up the engine was running hot. I pulled over and and the fill level was low. Really low. When I pulled off the cap to the tank the liquid leveled off. Not sure if there was a vacuum or something. The rest of the trip I had no further issues. Never figured out what the problem was but it worked.