I handle the oil changes on my moms 2017 GMC Terrain with the 2.4 4 cylinder. I try to keep oil / filter changes at 3000 mile intervals due to the reputation of this engine. I haven't been brand loyal with engine oil on this car, I generally give it whatever Dexos 5w30 is on sale at WM. So far that has been PP 5w30, Castrol Edge 5w30, Mobil 1 5w30 and just yesterday M1 EP 5w30.
Up until now upon draining the oil around the 3,000 to 4,000 mile mark the level has always stayed full with no notable oil usage. Well yesterday when I did the oil change, a full 6 quarts drained out. This has a 5 quart sump.
They just recently took it on a 1000 mile + trip so I had assumed my dad "topped off" the oil as is his custom before a trip, but he claims he did not. If that is the case then 1 quart of fuel was in the sump. My mom was there for the conversation and she thought that as some point recently, he had added some oil but he claims he did not. So I have no proof either way at this point. I'll just move forward with strict 3,000 mile OCI's to make sure that fuel doesn't have as long a chance to accumulate if that is even what is going on here.
Due to their road trip this oil change interval was just over 5,000 miles vs the usual 3,000-4,000. To me it seems odd that only 1000 miles would produce a noticeable increase in fuel dilution, especially with the last 1000+ miles being highway driven. Will monitor moving forward and update. Current mileage is 86,200 mi.
EDIT: I just checked the maintenance records, this was IN FACT a 3,000 mile oil change interval. Including the recent road trip. So I will closely monitor the oil level. Hopefully make up oil was added and he just forgot vs. heavy fuel dilution. Another though I am just now realizing, I did use an oil extractor with the two most recent oil changes. Maybe it didn't retrieve all 5 quarts with the previous change and some residual was left in the sump, resulting in an initial overfill. I am skeptical of that however, as I recall the extractor pulling out nearly 5 quarts. Time will tell.
Up until now upon draining the oil around the 3,000 to 4,000 mile mark the level has always stayed full with no notable oil usage. Well yesterday when I did the oil change, a full 6 quarts drained out. This has a 5 quart sump.
They just recently took it on a 1000 mile + trip so I had assumed my dad "topped off" the oil as is his custom before a trip, but he claims he did not. If that is the case then 1 quart of fuel was in the sump. My mom was there for the conversation and she thought that as some point recently, he had added some oil but he claims he did not. So I have no proof either way at this point. I'll just move forward with strict 3,000 mile OCI's to make sure that fuel doesn't have as long a chance to accumulate if that is even what is going on here.
Due to their road trip this oil change interval was just over 5,000 miles vs the usual 3,000-4,000. To me it seems odd that only 1000 miles would produce a noticeable increase in fuel dilution, especially with the last 1000+ miles being highway driven. Will monitor moving forward and update. Current mileage is 86,200 mi.
EDIT: I just checked the maintenance records, this was IN FACT a 3,000 mile oil change interval. Including the recent road trip. So I will closely monitor the oil level. Hopefully make up oil was added and he just forgot vs. heavy fuel dilution. Another though I am just now realizing, I did use an oil extractor with the two most recent oil changes. Maybe it didn't retrieve all 5 quarts with the previous change and some residual was left in the sump, resulting in an initial overfill. I am skeptical of that however, as I recall the extractor pulling out nearly 5 quarts. Time will tell.
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