My LML only has 45k miles, but its 5 years old, and time to service the cooling system.
As many of you know, GM in its infinite wisdom did away with any convenient way to drain the cooling system by deleting the radiator petcock.
I looked into not so convenient ways like block drain plugs, to no avail. Even removing the lower radiator hose looks like both a pain in the rear, and a guaranteed mess maker, with coolant spraying everywhere.
NOTE: Some may flame me for what I am about to describe doing. Thats ok. I did it as a lessor of two evils. I'm not a big fan of altering OEM stuff, but sometimes you have no choice.
First thing to do is jack up your truck, and get some room to work with. Then pop off the front plastic skid plate to get access to the lower radiator hose area. Next, pop off the clamp that secures the smaller hose ,to the larger one.
I went into the kitchen and grabbed these big scissors we have, that cut just about anything... and in a quick...SNIP, I cut the small lower hose in two.
![Image]()
Obviously, you want to do this with the truck cold. You plug one side with your thumb, while the other side drains into the bucket. I only lost a tiny bit of coolant when I did the Snip. It was quick and easy.
This hose is at the very lowest point in the cooling system,which is another reason for doing it this way, and will drain the entire system. Its about 3.5 gallons.
Next, you want to splice it back together. You will need a 5/8" splice, and two 1" spring clamps.
![Image]()
The splice fits a little loose, so the hose must be metric. If anyone makes a 17mm hose splice, this would fit perfect.
Splice it back together, and reinstall the OEM mounting clamp.
![Image]()
![Image]()
There is no "bleed plug" anymore either, so to refill the cooling system you need to fill it all the way up, start the truck, wait for it to get warm so the thermostats open, then fill it again.
And thats about it. Like I said, this method may not be for everyone, and thats understandable, but its one way to deal with the issue.
:gearjamin
As many of you know, GM in its infinite wisdom did away with any convenient way to drain the cooling system by deleting the radiator petcock.
I looked into not so convenient ways like block drain plugs, to no avail. Even removing the lower radiator hose looks like both a pain in the rear, and a guaranteed mess maker, with coolant spraying everywhere.
NOTE: Some may flame me for what I am about to describe doing. Thats ok. I did it as a lessor of two evils. I'm not a big fan of altering OEM stuff, but sometimes you have no choice.
First thing to do is jack up your truck, and get some room to work with. Then pop off the front plastic skid plate to get access to the lower radiator hose area. Next, pop off the clamp that secures the smaller hose ,to the larger one.
I went into the kitchen and grabbed these big scissors we have, that cut just about anything... and in a quick...SNIP, I cut the small lower hose in two.
Obviously, you want to do this with the truck cold. You plug one side with your thumb, while the other side drains into the bucket. I only lost a tiny bit of coolant when I did the Snip. It was quick and easy.
This hose is at the very lowest point in the cooling system,which is another reason for doing it this way, and will drain the entire system. Its about 3.5 gallons.
Next, you want to splice it back together. You will need a 5/8" splice, and two 1" spring clamps.
The splice fits a little loose, so the hose must be metric. If anyone makes a 17mm hose splice, this would fit perfect.
Splice it back together, and reinstall the OEM mounting clamp.
There is no "bleed plug" anymore either, so to refill the cooling system you need to fill it all the way up, start the truck, wait for it to get warm so the thermostats open, then fill it again.
And thats about it. Like I said, this method may not be for everyone, and thats understandable, but its one way to deal with the issue.
:gearjamin
