Problems w/ 2002 GMC Sierra 1/2 Ton 5.3L

[perkis]

Hello,
Hopefully this is the right forum to post this:

I have a 2002 Sierra with the 5.3L v8. It has 134K Miles.
This weekend when I went out to start it in the morning after it had been sitting all night, it had a noticeable ticking sound coming from the motor that I had not heard before. After a few minutes the ticking sound went away. Earlier last week the "Low Coolant" message came on the message center. I refilled with dexcool and water 50/50 mix. When I looked at the coolant reservoir this weekend, it was low again by 1.5 inches or so. I changed the oil in it this weekend since it was due. It took a long time for all the oil to drain out of the pan and towards the end there were black specs in the oil that was draining. It was not metal flakes as the black flecks would dissolve if pressed between my fingers. It seemed like sludge. The oil pressure has been a little bit high and the engine oil cap has some fluid in the top and it smells like coolant pretty bad. The temperature gauge has been reading normal but i fear it might be a head gasket going out. The ticking sound happened both mornings this weekend but went away after a few minutes. There was no ticking sound this morning when it had sat all night. The oil looked normal when I changed it. It has been using a little coolant but has not overheated and is running normally.

Any ideas or insight would be appreciated.
Feel free to ask for any clarification.

Thank you,

Tony

 

[Molson02536]

Hello,
Hopefully this is the right forum to post this:

I have a 2002 Sierra with the 5.3L v8. It has 134K Miles.
This weekend when I went out to start it in the morning after it had been sitting all night, it had a noticeable ticking sound coming from the motor that I had not heard before. After a few minutes the ticking sound went away. Earlier last week the "Low Coolant" message came on the message center. I refilled with dexcool and water 50/50 mix. When I looked at the coolant reservoir this weekend, it was low again by 1.5 inches or so. I changed the oil in it this weekend since it was due. It took a long time for all the oil to drain out of the pan and towards the end there were black specs in the oil that was draining. It was not metal flakes as the black flecks would dissolve if pressed between my fingers. It seemed like sludge. The oil pressure has been a little bit high and the engine oil cap has some fluid in the top and it smells like coolant pretty bad. The temperature gauge has been reading normal but i fear it might be a head gasket going out. The ticking sound happened both mornings this weekend but went away after a few minutes. There was no ticking sound this morning when it had sat all night. The oil looked normal when I changed it. It has been using a little coolant but has not overheated and is running normally.

Any ideas or insight would be appreciated.
Feel free to ask for any clarification.

Thank you,

Tony

There is a particular problem with one of the casting companies who made heads for this engine, castech is their name. At any rate here's the details from the tech bulletin. It's a crying shame that GM wont do anything given this is due to a defect in the casting of the heads.

Engine - Coolant Loss With No Visible Leaks
Bulletin No.: 06-06-01-019B

Date: June 12, 2007

INFORMATION

Subject:
Information on Gradual Coolant Loss Over Time With No Evidence of Leak Found

Models:
2004-2006 Buick Rainier
2001-2006 Cadillac Escalade Models
2001-2006 Chevrolet Avalanche, Blazer, Silverado, Suburban, Tahoe, TrailBlazer Models
2001-2006 GMC Envoy, Jimmy, Sierra, Yukon Models
2001-2004 Oldsmobile Bravada
2005-2006 Saab 9-7X

with 4.8L or 5.3L VORTEC® GEN III, GEN IV V8 Engine (VINs V, T, M, B, Z - RPOs LR4, LM7, LH6, L33, L59)

Supercede:

This bulletin is being revised to include engine RPO L59. Please discard Corporate Bulletin Number 06-06-01-019A (Section 06 - Engine/Propulsion System).

Some vehicles may experience a gradual coolant loss over time. A very low percentage of cylinder head(s) manufactured with an embossed Castech logo may develop a porosity crack in a very specific area.

Inspect the cylinder head assembly to determine if the casting was manufactured by Castech. This can be accomplished by inspecting for their casting logo located on top of the intake port, under the rocker arm support rail and in the spring deck cavity portion of the cylinder head.

If the cylinder head(s) are Not a Castech casting, follow normal diagnostic procedures in SI to determine the cause of the coolant loss.

Refer to the illustrations on how to identify Castech casting and/or the very specific areas of the cylinder head(s) for a coolant leak from porosity.

Cylinder head(s) location of the Castech manufacturing casting logo (1).

Close up view of the cylinder head(s) showing the Castech manufacturing casting logo (1).

If the cylinder head(s) is a Castech casting (1), inspect the area around the five oil drain holes for witness marks indicating coolant seepage over time (2).

If No evidence of coolant loss is found on inspection of Castech casting cylinder head(s), follow normal diagnostic procedures in SI to determine the cause of the coolant loss.

The crack location can be found in any of the five cylinder head(s) oil drains. This can be seen as a clean or shiny area, on an otherwise stained surface (1). Pressurizing the cooling system at this time may reveal coolant, air, or a combination, weeping in the described area. If inspection reveals evidence of coolant witness marks (1), replace the entire cylinder head(s) assembly.

GM bulletins are intended for use by professional technicians, NOT a "do-it-yourselfer". They are written to inform these technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions, and know-how to do a job properly and safely. If a condition is described, DO NOT assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See your GM dealer for information on whether your vehicle may benefit from the information. WE SUPPORT VOLUNTARY TECHNICIAN CERTIFICATION

Add a small bottle of "BarsLeak" to your coolant and this should temporarily solved the problem, but im not into rinky dink fixes. Also add the Can of Seafoam to your crank case oil or a bottle of Marvel Mystery Oil to clean out the oil journals from the sludge. Start with the Marvel first since i sounds like your engine is not to badly sludge up yet. Note that coolant in your engine oil will corrode your internal engine bearings, which will lead to a costly engine tear down.

http://www.seafoamsales.com/

http://www.marvelmysteryoil.com/

http://www.gm-trucks.com/forums/index.php?showtopic=78750

 

[perkis]

Molson,

Thank you for the quick response. Do you by chance have a link that shows the pictures to identify if the heads were made by castech?

I see that they only say "a very low percentage" of cylinder heads were made by castech but they don't give a number.

If they are indeed castech, is there anything I can do to recover any losses and what is an estimated cost for new heads if that is what is required and would it be worth it on a P/U with 134K miles?

Thanks again,

Tony

 

[Molson02536]

Molson,

Thank you for the quick response. Do you by chance have a link that shows the pictures to identify if the heads were made by castech?

I see that they only say "a very low percentage" of cylinder heads were made by castech but they don't give a number.

If they are indeed castech, is there anything I can do to recover any losses and what is an estimated cost for new heads if that is what is required and would it be worth it on a P/U with 134K miles?

Thanks again,

Tony

http://www.gm-trucks.com/forums/index.php?showtopic=78750

You may get lucky and the parts department at the Gm dealer my have it on record in there data base with the use of your vin number. Other then that follow the link above, sorry but i don't think GM will have any warranty programs for this issue. Your going to have to replace the heads and might as well replace the cam and lifters also since the engine is apart to get you more HP and better performance. There is a new design head gasket (dual shim) just to let you know to use when putting on the new heads and it would be impossible for it to be intake related for the 5.3 is a dry intake.

 

[03DumpRunner]

Molson

I've got an 03 GM Sierra with the 4.8 that is using some coolant (about 2-3 litres in the 2500km since i've owned it). The truck has 150K on it

Will this get worse? Will it lead to a head gasket failure?

The truck does not use any oil and the oil seems to be free of coolant so it looks like it is being burned.

What are the consequences of continuing to run the vehicle indefinitely and adding a bit of coolant now and then? At this point I can't notice any smell in the exhaust

Thanks
STeve

 

[Molson02536]

Molson

I've got an 03 GM Sierra with the 4.8 that is using some coolant (about 2-3 litres in the 2500km since i've owned it). The truck has 150K on it

Will this get worse? Will it lead to a head gasket failure?

The truck does not use any oil and the oil seems to be free of coolant so it looks like it is being burned.

What are the consequences of continuing to run the vehicle indefinitely and adding a bit of coolant now and then? At this point I can't notice any smell in the exhaust

Thanks
STeve

Have an oil analysis done on your next oil change, it's about $8.00 to see what condition your engine is in from the contamination you have in your engine oil and also inspect your transmission fluid for cross contamination.

Coolant is corrosive to the bearing to the engine and transmission, so servicing the engine oil and filter is more a necessity to be done to ensure a long engine life. The other common are for a leak is the water pump gasket, the pump is good, but the gasket goes bad. Inspect the the water pump gasket area for any signs of leak and replace the gasket if it is leaking.

Keep us posted and we can go from here.