1992 Surburban Big Block - M1 10W-30 - 5 year OCI

[bigt61]

From my 1992 Chevy Suburban 2500 w 7.4L engine. 57,000 total miles on unit. Truck spends most of it's life in a garage. This M1 10W-30 was at least a few years old before it went in August, 2011 - I think it was API SM.



This truck went 5 years between changes, but only 1781 miles. Most of the miles are short trips around town - less than 20 miles round trip - it did take a trip or two down to Va Tech pulling a small trailer - maybe 3-4000 lbs total - 500 mile round trip, but not in the last 3 years. Most of the truck's previous life was spent towing a 12,000lb race car trailer and running M1 15W-50. This short mile OCI saw a few ounces of make up oil a few years ago. Lead is only # I see that's even semi-high and I'm not concerned about it. TBN still strong after 5 years, it's possible I could have gone a few more years. I did not change the oil filter as it still looks brand new - on the outside - filter is an AC Delco Professional. I will change the filter at the next OCI 5 years from now. The truck was refilled w M1 0W-40 - it holds 7 quarts. This truck is not driven in the snow and rarely sees rain. My takeaway from this report is...if you're using a quality synthetic and don't drive much with a garage kept car, annual oil changes are likely a waste of time, money and resources.

 

[Ihatetochangeoil]

Thanks so much for posting this; it is truly informative. This is such a normal UOA that it is boring.....And 5 year OCI...Methinks you could go 8...and some folks won't spring for a UOA to learn this stuff...

May I ask you; what is approximately the AVERAGE garage temperature? Is it heated at all? For example, MY garage is totally unheated; but I live in a "split foyer" home with an upward sloping backyard...My garage is about 3/4 underground, the ceiling and 2 walls adjacent to heated living quarters and has insulated doors...It will be about 55 degrees inside (with the doors shut) when it is well below freezing outside. Comfortable for the cat and the cars never freeze.

Again, thanks for posting this. I run full synthetic and the cars are garaged at night. FWIW, I have UOA with 36 ppm lead and the test lab said it's (normal) OK.

 

[Rolla07]

Id be curious to know how the filter is holding up after 5 years..I know you said looked fine on outside but what about anti drainback valve and media? I think id be more worried about filter than oil in this case.

 

[dareo]

Wow, 5 years, that takes guts. Thanks for the results!

 

[69GTX]

Excellent info. My '99 gets only 1400 miles per year with no trips less than 13-15 miles. Was doing an annual oil change with M1 0w-40 + Fram UG. I'll have to rethink this. And to think 2 years ago I was doing 6 month oil changes with M1 at 700 miles! Doh!

 

[Ethan1]

Be honest: did you forget to change your oil for five years, then decide to do a UOA after the fact?

 

[crazyoildude]

Im beginning to think Mobil 1 is my best choice for synthetic oil I switched from QSUD which was ok also but so far im very happy with the switch to Mobil 1 its easy to find and is very well known and goes on sale from time to time and sometimes also has a good rebate like Now...lol

 

[bigt61]

Ihatetochangeoil - The garage is unheated and detached from my house. Water will freeze in the garage if temps stay around 0F for an extended period. The garage has no shade so I would say it gets hotter in the summer and the daytime sunlight keeps it warmer in the winter.

Rolla07 - Yea, the filter is a bit of a dice roll but I think it will be fine. I'll let you know in 5 years after I cut it open. The AC Delco Prof 1218 has silicone anti drain back and seems to be built well - it's well sealed on the engine and had zero drips around the body.

Ethan1 - Haha, no I didn't forget, it was planned for August 2016 a few years ago. I do many oil changes in that garage - my kid's cars and friend's cars & trucks.

If I was doing more miles - say 5000 miles in 3 years - I would probably change it then. Miles and hours in use degrades oil far faster than just sitting in the sump. Being in a garage helps.

 

[shinyWheels]

Wow 5 years. I always wondered how they came up with time intervals as if oil spoils. I suppose some degradation if it's sitting in very cold freezing weather. The old 3 month / 3k miles rule is so obsolete.

 

[BigD1]

Got one of the NAPA kits to pick up in the morning. Hope the results come back fast like your results did.

 

[meborder]

Originally Posted By: BigD1
Got one of the NAPA kits to pick up in the morning. Hope the results come back fast like your results did.


They are pretty timely for the most part.

Dont mail it in the tube. It's legal, but it can roll off the belt and get lost. Pay the extra money and ship it priority in an envelope so it doesn't get lost.

Speaking from experience.