Sludge concerns

Messages
1,821
Location
South Dakota
My coworker has a 2012 Buick Enclave with approximately 142k miles. She had to have new cam sensors installed. While it was in, the dealership noticed that it was severely sludged in the timing chain. They replaced the timing chain and changed the oil while they had it in. She did oil changes based on the Oil Life Monitor. Dealership told her to change the oil every 4k miles and ignore the OLM or switch to full synthetic and go about 6k miles. I have a 2016 Dodge Grand Caravan. I use full synthetic and go by the OLM. Based upon the OLM, I usually go about 10k miles before changing oil. I'm concerned about the possibility of sludge. Recommendations?
 
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Messages
26,076
Location
Upstate NY
Pull valve cover and visually inspect. Although synthetic is always a good idea. Given NAPA synthetic on sale for $16.99 I cannot see people using conventional oil.
 
Messages
18,336
Location
NH
You can pull a valve cover, that'd be best, although I wonder if those newer endoscopes would work well enough. Full synthetic, not sure if I would worry too much. Based on a number of photos here, I wouldn't worry much about it, not at your miles. If you're not short tripping then I am dubious about problems.
 
Messages
10,875
Location
Jupiter, Florida
I keep beating the "synthetic" drums here. OLM and UOA results can't tell if your oil is causing sticking piston rings, sludge, worn timing chains and so on. Example after example exist. Yet people fail to understand the costs involved with poor maintenance. People continually argue that the manufacturer knows best! What they know is how to sell you another vehicle. They do not have an interest in your vehicle lasting a lifetime. As always, the best results are found using a quality synthetic and changing the oil regularly. I suggest every 5000. That way, OC's are done at 15,000, 20,000, 25,000 etc.
 
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Messages
5,095
Location
VA
Some may think I'm a little backwards, but I will never go by the OLM. She followed the OLM and that practice "appears" to have hurt her engine. I change all of my cars (and the others I take care of) between 3-5K. One car goes 8 miles to work and it gets changed every 3K. Another car goes 35 miles to work and it gets changed every 5k. 2 cars aren't driven 5K/year and they get changed every 6 months. I'd use "synthetic" oil and not extend the OCI but just to help clean my engine up. SInce she knows she had a problem, I'd do a 3k OCI with factory OEM filter.
 
Messages
8,786
Location
Champlain/Hudson Valley
What engine? Is it a known "sludger" or, at least, a hot running engine? Any idea about where she has had her oil changed over her 142K? She may have gone with real cheap oil. Did she follow the OLM or say she did? (sorry) Plus, the stealership saying her timing chains needed to be replaced isn't the most comforting source. Does her engine eat chains by 150K?
 
Messages
294
Location
MN
2012 Enclave has the 3.6 LLT V6 which was the famous timing chain stretcher. As a service/tech bulletin the OLM was revised to 5000 mile max OCI's, but there is no guarantee the owner ever had that bulletin done. Previously OLM's for these vehicles would call for oil changes at 10,000+ miles. In an engine famous for tearing up even synthetic oil by 5-6000 miles in addition to being installed in a 5000 lb vehicles, the engine works hard and should have 5000 mile max oil changes on synthetic. To the OP, not sure how your 3.6 treats it's oil, but to my knowledge those were still port injected? If that's the case they are probably quite a bit easier on oil, but maybe have your 10k oil tested to see how it tests after that many miles, that's the only way to know for sure.
 
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Messages
14,854
Location
Illinois
Originally Posted by Cujet
I keep beating the "synthetic" drums here. OLM and UOA results can't tell if your oil is causing sticking piston rings, sludge, worn timing chains and so on. Example after example exist. Yet people fail to understand the costs involved with poor maintenance. People continually argue that the manufacturer knows best! What they know is how to sell you another vehicle. They do not have an interest in your vehicle lasting a lifetime. As always, the best results are found using a quality synthetic and changing the oil regularly. I suggest every 5000. That way, OC's are done at 15,000, 20,000, 25,000 etc.
I fully agree although my 42 year usage of M1 oils has given me like new clean engines with never TC or any other internal engine problems like coked rings. All at 10K OCIs.
 
Messages
26,360
Location
MA, Mittelfranken.de
Originally Posted by Cujet
I keep beating the "synthetic" drums here. OLM and UOA results can't tell if your oil is causing sticking piston rings, sludge, worn timing chains and so on. Example after example exist. Yet people fail to understand the costs involved with poor maintenance. People continually argue that the manufacturer knows best! What they know is how to sell you another vehicle. They do not have an interest in your vehicle lasting a lifetime. As always, the best results are found using a quality synthetic and changing the oil regularly. I suggest every 5000. That way, OC's are done at 15,000, 20,000, 25,000 etc.
Best answer IMO! Oil is dirt cheap engines and major repairs are not, pay me a few bucks now or pay me a big chunk later.
 
Messages
1,868
Location
SW Ontario Canada
When the GM OLM system was introduced, and subsequently explained in great detail, it was hailed as one of GM's good ideas. Fast forward 15 years, and now it is causing engine damage for those that abide it's suggestions? To state the obvious, GM is overdue for a re-calibration of the parameters in the new era of high feature, hotter engines, hotter environments.
 
Messages
17,871
Location
...
How was this car driven? Lots of idling? Short trips? Is she the original owner? Sludge occurs for many reasons.
 
Messages
8,786
Location
Champlain/Hudson Valley
^^ THIS ^^ Also: "...GM is overdue for a re-calibration of the parameters in the new era of high feature, hotter engines, hotter environments." Is it possible an auto maker made up one set of OLM parameters and installed it into every single application? How disengaged would that be? I never had an OLM but I assume it can be set for the owner's climate or expected usage (severe vs normal).
 
Messages
2,156
Location
Winnipeg MB CA
We used the OLM on my last work truck (2013 Chevy Silverado 2500 6.0 4WD) to determine service intervals. The truck had typically racked up about 10,000 km (c. 6000 miles) by the time the OLM got down to 10%. It's interesting to hear of these 10K mile OLMs on US vehicles; the difference is likely due to our cold weather, and how our truck did a fair number of short trips.
 
Messages
7,449
Location
Los Gatos, CA
Originally Posted by Cujet
I keep beating the "synthetic" drums here. OLM and UOA results can't tell if your oil is causing sticking piston rings, sludge, worn timing chains and so on. Example after example exist. Yet people fail to understand the costs involved with poor maintenance. People continually argue that the manufacturer knows best! What they know is how to sell you another vehicle. They do not have an interest in your vehicle lasting a lifetime. As always, the best results are found using a quality synthetic and changing the oil regularly. I suggest every 5000. That way, OC's are done at 15,000, 20,000, 25,000 etc.
I have followed this service schedule since new with our 2006 TSX with the mighty K24. Mostly M1 5w30 or 5w20, M1 or Wix filters. 198K miles later this thing is spotless. I service 2 other 2007 TSXs, one with 85K and 1 with 110K. These were serviced by a mix of dealer, quickie lube and ? before I got them. Our car is seems to be better as their cars go through a little oil between services.
 
Messages
3,668
Location
St. Charles County, Missouri
One of the original inventors of the OLM for GM was on here before getting ticked off at Amsoil salesmen. He lasted a couple of months IIRC. In coming over to the Soul from a '14 Encore the OLM was one of the things I missed. Used to change at about the 20% mark. However, my original GM OLM was in a 3.5 liter Malibu Maxx. That thing was an exceptionally trouble free engine and the OLM was great in that car. The Encore didn't have any major problems but had ongoing PCV/valve cover replacements and I'm happy to have the Soul, fewer problems even with its reputation. As far as the lack of an OLM, I'm happy just to divide by five. Times are different than in 2005.
 
Messages
2,165
Location
USA
Old school auto mechanics 101. Cold weather and/or short trips cause sludge. Cool running engines cause sludge. 4-5 K intervals in the winter may not be even enough in your climate. You have to be the final judge of how the car is being used.
 
Messages
14,854
Location
Illinois
Originally Posted by Farnsworth
Old school auto mechanics 101. Cold weather and/or short trips cause sludge. Cool running engines cause sludge. 4-5 K intervals in the winter may not be even enough in your climate. You have to be the final judge of how the car is being used.
Only partially true.
 

otis24

Thread starter
Messages
1,821
Location
South Dakota
Originally Posted by supton
You can pull a valve cover, that'd be best, although I wonder if those newer endoscopes would work well enough. Full synthetic, not sure if I would worry too much. Based on a number of photos here, I wouldn't worry much about it, not at your miles. If you're not short tripping then I am dubious about problems.
Unfortunately, the vehicle sees lots of short tripping. Live in a small town. When we go "out of town" it is 75 miles minimum.
 
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