[bazar01]

Got a message on the DIC "Low Coolant". It has 290k miles. WP replaced around 150k miles. Radiator, hoses and connectors are original. Reservoir level is very low. I saw coolant dripping at the back of the engine oil pan under cover. Probably dripping on the under cover and running down the back.
I'm going to park it for a while until I can find time to investigate as I am going out of town for a few weeks.
Any guesses?

 

[Cowboytrukr]

Bel, whet engine do you have?

 

[bazar01]

Hey Greg, it's a 2001 burb 2wd with the 5.3L.

I'll pressure test it when I get back in town.

 

[Cowboytrukr]

Ok, good. I was worried you had the 8.1. It’s a blessing and a curse. I will be posting my radiator woes with my 8.1.

 

[OpalLacod]

Heater core plastic hose connector at the firewall for the cheap win!!!

 

[Rebel_Bowtie]

Jake’s x2. Water pump would be leaking down the front of the block, although you’re probably due for another one soon.

 

[Thespaguy]

Things to do to be prepared. Go to the help isle at any auto parts store and get an extra or even two extra inlet or outlet couplers that go to your heater core. I have a 2001 2500HD 6.0 and my radiator was leaking right where one of the hoses go into it. It is usually a very small and slow leak until it starts to crack more. Must of the time it will be the inlet couplers. I would definitely check your water pump. I have replaced mine once before. It cracks then leaks from it's seals. It will drive for awhile but replacement asap if you can.

 

[bazar01]

Thank you for the advice.

I know I have a complete set of hoses and plastic fittings I bought a few years back and had planned on replacing the original ones but never got around doing it. I have to find them though and they are in a box some place in the attic. I hope they are not dry rotted. 😒
Won't be able to work on it til next two weeks.

 

[Thespaguy]

Thank you for the advice.

I know I have a complete set of hoses and plastic fittings I bought a few years back and had planned on replacing the original ones but never got around doing it. I have to find them though and they are in a box some place in the attic. I hope they are not dry rotted. 😒
Won't be able to work on it til next two weeks.

Ahhh... If they are dry rotten then they are very cheap! I literally have an extra one I have thrown in my glove compartment with a drive belt in one of the back seat pockets. They will break more frequently if you drive through a lot of flooded roads. You have hot coolant on the inside and cold water on the outside then Crackle snap pop you have coolant everywhere.

 

[Brenden16]

Got a message on the DIC "Low Coolant". It has 290k miles. WP replaced around 150k miles. Radiator, hoses and connectors are original. Reservoir level is very low. I saw coolant dripping at the back of the engine oil pan under cover. Probably dripping on the under cover and running down the back.
I'm going to park it for a while until I can find time to investigate as I am going out of town for a few weeks.
Any guesses?

Dealt with a similar issue on my old 06 Z71 before it was totaled. Gonna say it’s your water pump weep hole, all of the coolant would seep down and drip behind the pan. Literally just had this job done 3 months ago (2 weeks before my wreck...) change out the water pump ($110 on Amazon & $200 in labor if you don’t do it yourself) and you should be good.

Hope this helps man!

 

[RayVoy]

Bel, if it's coming down the back of the engine, I'd be suspicious of a leaking freeze plug.

 

[Cap'n Jack]

Is there a metal option for the hose connection (GMC part)? I seem to recall changing mine out ~20 years ago.

 

[bazar01]

Dealt with a similar issue on my old 06 Z71 before it was totaled. Gonna say it’s your water pump weep hole, all of the coolant would seep down and drip behind the pan. Literally just had this job done 3 months ago (2 weeks before my wreck...) change out the water pump ($110 on Amazon & $200 in labor if you don’t do it yourself) and you should be good.

Hope this helps man!

Everything helps, thanks.
I'm still out of town and can't get to it until last week of May.

 

[bazar01]

Bel, if it's coming down the back of the engine, I'd be suspicious of a leaking freeze plug.

Thanks Ray
I'll update when I get back in town last week of May.

 

[bazar01]

Finally home yesterday.

Started working on removing the MAF intake tube, upper and lower fan shroud and fan clutch.
Now I can see the wet surfaces. The coolant leak is behind the water pump on the passenger side.
Tomorrow I will remove the old water pump, install new water pump, new hoses and plastic heater Tee connectors.

@Brenden16 guessed it right. It was the water pump but the leak is not on the weep hole due to a bad bearing. The leak is on the passenger side water pump coolant inlet gasket. I think the gasket silicon surface area is so thin and it easily breaks away from the metal support. The water pump bearings were still good and quiet. If only I had known, I would have just bought the gasket set. Oh well, I already have the new water pump so it will go in.

Dealt with a similar issue on my old 06 Z71 before it was totaled. Gonna say it’s your water pump weep hole, all of the coolant would seep down and drip behind the pan. Literally just had this job done 3 months ago (2 weeks before my wreck...) change out the water pump ($110 on Amazon & $200 in labor if you don’t do it yourself) and you should be good.

Hope this helps man!

 

[bazar01]

Second water pump failed on gasket at only 123k miles. First one leaked at 167k miles.

Done. No rusted or broken water pump bolts.
New water pump and thermostat, all new hoses and heater plastic fittings and new AC compressor belt.
Added a little more silicon gasket maker around the metal gaskets for better sealing.
Filled it up with 60% Dexcool and 40% distilled water.

Good for another 100k miles? I will find out if the 5.3L engine and 4L60e holds up.

 

[Brenden16]

Hey Bel, glad to see you got her fixed up. Happy to see I was able to help out and it turned out to be something simple like the pump. With that completely new set up from pump to hoses you should be good to go. Hopefully she’s still running like a champ with no issues on the new pump. (Hopefully you’ll get more than 300 miles out of it like mine had before my crash in February!) Alas, you’re not leaking like a sieve! All the best!

 

[bazar01]

Yeah still running smooth at 290k miles.
Thanks @Brenden16 .

 

[bazar01]

I have a coolant leak again!
I wonder where?

 

[Brenden16]

I have a coolant leak again!
I wonder where?

View attachment 171549

Damn Bazar... that’s a bummer man. First thing I would do is look on the block and see if you can find where it’s dripping from. Check that water pump again too, could easily be one of those passenger seals again if not the weep hole. At least you managed to get about 10K on her in the meantime between the last leak. You sure do drive a lot lol, in the last 9 months I’ve only put about 4K miles on my 05, but I’m not like most.