Block Drain Plug

2005LT · November 24, 2007

Hello everyone,

I am new to the forum with today being my first post. I have just purchased a 2005 Chev Silverado 4x4 with the 5.3L aluminum block. The issue at hand is that I have to install a block heater (coolant heater) since I live in Edmonton, Alberta, Canada. I have the heater itself but I need to remove the coolant drain plug on the rear of the driver side block. I expected the plug to just be a STANDARD hex and removable with a wrench. Problem is, its a weird shape. Almost like an allan key but different. Is this a dealership-only special tool to remove this thing? See pics below:

One last item. Is there a radiator drain plug on this truck? Myself and neighbor who is a mechanic by trade spent a combined 20 min looking for it and couldn't find it. Approximately where is it? Thanks a lot!

MS3DALE · November 24, 2007

First off,Welcome aboard!!

Secondly,No,Its not a special tool,Just a 17mm hex-head socket,I bought one off my Snap-On dealer (Part#SAM17E) when I installed a block heater on my '04.

Thirdly,No,Theres no radiator drain plug,They took'em out sometime between '99 and '04 (My '99 had one,My '04 did not)

You either have to just remove the plug and let whatever coolant comes out comes out,or remove the lower radiator hose at the radiator.

Also it might help if you unbolt the front of the front driveshaft so you can move it out of the way to get your extension/socket up there to remove the plug and install the heater,At least it made it easier for me with it out of the way.

az'03Silverado · November 24, 2007

My '03 has a drain plug so they must have stopped installing them in '04. The hex wrench you want is the same size as the transmission drain plug wrench for any old VW Bus, Bug, etc. It's a 17mm hex. A company called EMPI makes one that looks like a big allen key and they also make one that's a socket for a 1/2in. drive.

2005LT · November 25, 2007

Thanks a bunch for the tips guys. Really appreciate the response.

MS3DALE · November 25, 2007

One other thing,In GM's infinete wisdom they put a thermostat in the heater cord plug that won't let it come on until the outside temperature is 0 degrees or less.

Some guys on here have cut it open and removed it to disable that stupid design!

Jaredkm · November 25, 2007

Maybe I am few and far between, but I am glad that my plug has that thermostat that does not let it draw power until it is 0' F (-18'C). I normally wouldnt start plugging in my truck till it was that cold anyways. I live even furter north than Edmonton, and it can get pretty cold up here in the chilly Canadian north. Even my civic I wouldnt start plugging it in until it was about -20. Just my .02

svensk · November 25, 2007

Maybe I am few and far between, but I am glad that my plug has that thermostat that does not let it draw power until it is 0' F (-18'C). I normally wouldnt start plugging in my truck till it was that cold anyways. I live even furter north than Edmonton, and it can get pretty cold up here in the chilly Canadian north. Even my civic I wouldnt start plugging it in until it was about -20. Just my .02

Yeah, my Sierra will crank right up after sitting at work for 14 hours during a -30-40 spell we had last winter. Just make sure you have a good battery.

2005LT · November 26, 2007

True enough. The heater I bought does not have a thermostat in it (called the manufacturer and talked with a technician to make sure). I like to think that its better for the engine to start when its warmer (extend the engine life). It will start when its really cold, no doubt. It would just be easier on the whole system when its been plugged in for a few hours that's all.

MS3DALE · November 26, 2007

Where and what brand heater did you buy?

Just wondering since all the GM ones have the thermostat and yours don't.

WilliamBos · October 10, 2009

Where and what brand heater did you buy?
Just wondering since all the GM ones have the thermostat and yours don't.

What year did they put the T-stat in the block heater cord?? I have not plugged ours in yet, and we had days of -40c last winter, fired right up!!

MS3DALE · October 10, 2009

Man,Old thread brought back to life!

First off...I ended-up buying a block heater from NAPA,which does NOT have a thermostat,to replace my factory one which did!

Secondly...I'm not exactly sure what year they started putting a thermostat in them,I know my '04 had one,and my '99 did not.

WilliamBos · October 10, 2009

Man,Old thread brought back to life!
First off...I ended-up buying a block heater from NAPA,which does NOT have a thermostat,to replace my factory one which did!

Secondly...I'm not exactly sure what year they started putting a thermostat in them,I know my '04 had one,and my '99 did not.

Is the T-stat in the block heater itself?? When did they do away with that PITA frost plug style, and go with the screw in style? The screw in is far superior IMHO.

txab · October 10, 2009

Thermostat is located in-line on the power cable

2005LT · October 11, 2009

Sorry about missing your question back in 2007 Rich Like you I got the block heater for that 05' Silverado at NAPA without a thermostat. The threaded style plug was an excellent idea and made the install easy.

MS3DALE · October 11, 2009

Sorry about missing your question back in 2007 Rich Like you I got the block heater for that 05' Silverado at NAPA without a thermostat. The threaded style plug was an excellent idea and made the install easy.

No problem