Radiator drain and fill on Avalanche

[INDYMAC]

I plan to start doing some radiator drain and fills on my daughter's 2008 Avalanche at 66K miles. I noticed that the last time I changed the oil, there was no radiator cap to refill radiator. Is the resupply route through the reservoir only? Anything to watch out for?

I plan to just stay with DexCool 50/50 premixed.

 

[ls1mike]

No radiator cap. Just through the reservoir.

 

[INDYMAC]

Thanks.

 

[Chris142]

How do you plan on draining it?

 

[INDYMAC]

I was just planning to open the drain valve. There is a drain valve, isn't there?

 

[Chris142]

Gm stopped putting in drain valves in 03. You will need to pull the lower hose and the heater hoses on the bottom of the wp.The thermostat is on the bottom so just pulling the lower hose won't drain the engine but the heater hoses areon the other side of the thermostat. You will need a big pan to catch the coolant since it will be everywhere!

 

[INDYMAC]

If I pull all of the hoses to drain the radiator and engine, will there be a problem with air pockets after I refill through the reservoir? How would I burp it?

 

[cp3]

Put it on your shoulder, don't forget the towel first!

Good question, I'm going to be doing this on my Son's Saturn probably this weekend. Never thought about this, always used to just leave the cap off the rad for a bit. Hard to do when there isn't one there.

 

[Chris142]

Originally Posted By: INDYMAC
If I pull all of the hoses to drain the radiator and engine, will there be a problem with air pockets after I refill through the reservoir? How would I burp it?
Fill the reservoir. The level will drop as it pushes air past the Jiggle valve. Fill it and repeat untill the fluid level no longer drops. Put the Radiator cap on the bottle and run it @2000 rpm until the thermostat opens. Shut it off and walk away. Recheck when it has cooled.

Same thing for C3P'S Saturn.

 

[Sayjac]

Originally Posted By: Chris142
Gm stopped putting in drain valves in 03.
Is this just for the Avalanche, GM trucks, or all GM? Bummer for diy.

 

[Chris142]

Originally Posted By: sayjac
Originally Posted By: Chris142
Gm stopped putting in drain valves in 03.
Is this just for the Avalanche, GM trucks, or all GM? Bummer for diy.

All GM cars and trucks as far as I know. Many of the aftermarket Radiators don't have drains either.

 

[INDYMAC]

Thanks Chris142. Sounds like a good plan. I only have 2 gallons of DexCool premix, so I'll have to buy a couple of more gallons I guess.

 

[SteveSRT8]

Be very cautious with the refill. These engines are challenging to get primed up and filled correctly, and the last thing you want is hot spots or steam bubbles.

Pull the lower hose to drain. Use the upper hose to fill it. Then fill the reservoir. Watch the temp gauge like a hawk until you are sure it is stabilized, as it can shoot up suddenly!

 

[Boss302fan]

I have a drain on my radiator for my 2004 Impala SS...

 

[gmctodd]

It might have been 05. My 05 2500HD had one, my 06 3500 does not

 

[The_Eric]

We've got an 04 Pickup in the shop now that doesn't have a drain.

 

[Audios]

Crack the lower hose or take out a freeze plug on the block.

 

[Chris142]

Originally Posted By: The_Eric
We've got an 04 Pickup in the shop now that doesn't have a drain.
Same with my GF's 04 Tahoe.

 

[GMorg]

My '05 Montana has a drain plug and a cap. It also has two bleeders. One above the pump and one on the return hose mount on the block side. On the Montana, the return hose is higher than the cap opening. Due to a bend in the hose, it is almost impossible to get the air out of the hose bend - even with the hose disconnected. I changed the DexCool yesterday.