Need help- 05 Gmc Sierra 5.3 (heavy towing&sludge)

Messages
30
Location
Georgia
Love the forum. Not sure why I'm so interested in reading about oil, but I read daily lol. I have a 2005 GMC Sierra 4x4 with a 5.3 vortec. I have owned several of these trucks with this engine and never had an issue like this. Previous oil changes before this latest one were clean. No visible issues at all. I pull my 24' camper, 21' bass boat, and 16' lawn maint. trailer. I was running pennzoil semi syn. 5w-30 with ac delco filter. 5,000 mile oci. I changed the oil a couple of weeks ago and the filter was completely full of sludge. The oil was really thin and jet black. When I say chunks I mean like, I dug this stuff out of the filter with a screw driver... When I refilled I went with Supertech Full Syn. and an ac delco filter. Any thoughts?? Suggestions??? Or is there anything to worry about?? I tow with the truck 90% of the time. I have a company truck that I drive daily so this is my truck that I play with on the weekends...
 
Messages
677
Location
USA
Your filter did its job by keeping the sludge and chunks out of the engine. I would not worry too much, but if you are getting those results then I would run your OCI at 4K miles on that supertech. A blend may be good for that long as well but its likely the engine is chewing the oil up due to the towing loads and heat. Pics of the filter?
 
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7,430
Location
beaver land EH?
There's a cause and there's consequences. You are telling us the consequences, you need to explore/find out the cause. Is your thermostat faulty? Did you buy this vehicle used with unknown service/maintenance history? and the list goes on... Q.
 

4Scott4

Thread starter
Messages
30
Location
Georgia
I do have pics! Can't figure out how to post em. I have a photobucket account. What tag line would I use to post them?
 

4Scott4

Thread starter
Messages
30
Location
Georgia
I did have one over heating issue during the oci but it was due to low coolant and truck ran just above normal temp for just a minute.. I shut it down immediately. I don't think it was enough to cause the issue?? Possibly??
 
Messages
39
Location
Georgia
Same thing happened to me on an 05 Chevy. Ended up being a cracked head. Apparently they had a problem for a few years including 05 with Castech heads cracking. Chevy mechanic called it a cracktech head. Get it checked out.
 
Messages
526
Location
Curtice, OH
Originally Posted By: Quest
There's a cause and there's consequences. You are telling us the consequences, you need to explore/find out the cause. Is your thermostat faulty? Did you buy this vehicle used with unknown service/maintenance history? and the list goes on... Q.
My thoughts exactly. SynBlend 5w30 should not have had an issue with a 5k run, towing or not. I would personally go with something more like Rotella T5 10w30 for your application, but any good 5w30 Synthetic shouldn't have a problem towing in a 5.3.
 
Messages
5,651
Location
Iowa
Originally Posted By: Quest
There's a cause and there's consequences. You are telling us the consequences, you need to explore/find out the cause. Is your thermostat faulty? Did you buy this vehicle used with unknown service/maintenance history? and the list goes on... Q.
Agreed. A UOA will help to point you in the direction of the cause. This engine shouldn't have sludged up under that usage. Could be from coolant intrusion from a head gasket or a faulty head (this engine was noted for that- certain castings) and/or excess fuel. Either way, a UOA would conofirm either of those.
 
Messages
5,651
Location
Iowa
Originally Posted By: Alex38
Originally Posted By: Quest
There's a cause and there's consequences. You are telling us the consequences, you need to explore/find out the cause. Is your thermostat faulty? Did you buy this vehicle used with unknown service/maintenance history? and the list goes on... Q.
My thoughts exactly. SynBlend 5w30 should not have had an issue with a 5k run, towing or not. I would personally go with something more like Rotella T5 10w30 for your application, but any good 5w30 Synthetic shouldn't have a problem towing in a 5.3.
Fixed it for you...
 
Messages
501
Location
not Sweden
Originally Posted By: 4Scott4
Any thoughts?? Suggestions???...I tow with the truck 90% of the time.
Amsoil ASL 5W-30: http://www.amsoil.com/shop/by-product/mo.../?code=ASLQT-EA Amsoil Ea15K32 Filter: http://www.amsoil.com/shop/by-product/fi...code=EA15K32-EA And given your frequent towing, upgrade your transmission fluid (and change your tranny filter while you are at it): http://www.amsoil.com/shop/by-product/tr.../?code=ATLQT-EA But I do agree a UOA would help to diagnose if you have a core issue beyond any brand/OCI/viscosity issues that needs to be addressed first.
 
Messages
7,180
Location
CT
Why was the coolant low? The coolant should never be low unless there is a leak... This is not an oil problem, that's not severe service for that motor and you could follow the OLM way past 5k and the motor would run forever.
 
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