Oil change interval for seldom-driven car

Messages
372
Location
Rancho Cucamonga, CA
My '94 Mustang GT recently got relegated to weekend driver/emergency backup status. At the rate I've been driving it the past 2 months, I'll have a hard time putting 3000 miles on it in a year. Is it kosher to leave 5 qts in a car for a year, or should I change it more often to keep the oil fresh? I was thinking maybe twice a year, but I don't know, does oil go stale sitting in there that long? Thanks, Tim
 
Messages
3,683
Location
Chattanooga, TN
Well, depending on climate and whether you drive it at least 10 miles to really heat it up the majority of times you do operate it then one year is fine. I have one that last year I put on 2100 miles, same oil and filter, analysis fine after twelve months.
 

timzak

Thread starter
Messages
372
Location
Rancho Cucamonga, CA
Thanks for the reply. The vast majority of the time, it's driven 5 miles or less. On a rare occasion, I'll take it for a 50 mile round trip to work or to visit family.
 
Messages
472
Location
Cleveland, GA
Well, being a 1994 your manual probably says 3000 miles or 3 months...right? If so...there is your answer. I would still change it every 3-4 months...regardless of miles driven.
 
Messages
903
Location
CA
If your oil can't retain TBN for a year with low mileage then something's wrong with your oil. Use a decent oil and change it once a year.
quote:
Originally posted by Scooby: Well, being a 1994 your manual probably says 3000 miles or 3 months...right? If so...there is your answer. I would still change it every 3-4 months...regardless of miles driven.
 
Messages
47,644
Location
Duvall WA - Pacific NW USA
Just pay for analysis at 6, then 9, then 12 months....peace of mind. And as said: if the oil has too much H2O, then drive it more or change storage conditions, or further investigate. If the TBN is toast, do the above and change oil type/brand.
 

Al

Messages
19,167
Location
Elizabethtown, Pa
quote:
Originally posted by Spector: Well, depending on climate and whether you drive it at least 10 miles to really heat it up the majority of times you do operate it then one year is fine.
Defenitely agree here-You need to get it hot when you drive it or at least before it sits say more than a few days.
 
Messages
418
Location
OR
These 3 UOA's will cost about $75. That will pay for a whopping 9 oil changes assuming he uses $1/qt dino juice and a std. filter. If I were the poster, I'd make sure that the car get's a good workout whenever it's driven and then just change the oil once a year. For added protection I'd use an oil with Moly. (Pennzoil Longlife for dino or Redline if he wants a synthetic)
quote:
Originally posted by Pablo: Just pay for analysis at 6, then 9, then 12 months....peace of mind. And as said: if the oil has too much H2O, then drive it more or change storage conditions, or further investigate. If the TBN is toast, do the above and change oil type/brand.
 
Messages
2,230
Location
SE MI
yeah seriously - UOAs are way too expensive and over-rated. Just change it every 3 months regardless of mileage. that's what I do with my seldom driven cars. I use SuperTech filters and Chevron Supreme oil.
 
Messages
2,480
So guys, you're saying if you store a car for 6 months, it should have 2-3 oil changes just for sitting around??? I disagree. Just change it before storing...and if driven seldom, any good synthetic should last 1 year or max. normal oil change interval...which ever comes first. eg. should have no problem with 7k/1yr.
 

Al

Messages
19,167
Location
Elizabethtown, Pa
Just compromise: Take a sample after one year. Basically-that's what I do on my Toyota Truck. It does use synthetic-but it had 6K after one year and the oil was fine. I really don't see why a dino oil after one year with 3K would not be fine also. Not trying to continue an argument-just looking for a solution. 2 or 3 changes just seems like overkill to me. [I dont know]
 
Messages
951
Location
Loveland, Colorado
Like I've said before, it all comes down to an individual's comfort level. (And a lot of times, we ask questions looking for an answer which matches what we've already decided.) I'm in the leave-it-in camp, & agree 100% with Spector, satterfi, Al & Dr T. Use a quality oil & leave it there. Any quality oil should have enough TBN for a year, but if it's creating worry, simply switch to something like Saab's OE 5W-30 semi-syn ($2.99/qt?) with its huge TBN reserve. (That stuff will probably go for 2yrs on that TBN!) My comfort level is now bordering on Caribbean/Jamaican for my oil changes. (Ya man, don'cha worry 'bout no bad ju-ju setlin' down'n dat basin, bra'...) In eight months I've put about 2700 miles on my 4qts, & it's not coming out until I reach 10k. And while I agree that UOAs are expensive, keep in mind that they're a tool. A lot of people take a used car & pay a mechanic to look it over before buying it. If the mechanic finds nastiness & you don't buy the car, is that $50-$100 wasted? You don't have to analyze every 3mos; do it when you change the oil. Then decided how long the next batch can stay in & test it again when that oil comes out. Once you establish how your car treats the oil, you can make an informed decision about change intervals without guessing or worrying about it. And when you have that info, you can then decide if continued UOAs are necessary, or if you're happy with what you've got.
 
Messages
2,230
Location
SE MI
Just use a quality dino and change every 3-6 months. That's what I do. Its exposed to air during that period and it will undoubtedly contain moisture and other oxidants.
 
Messages
1,856
Location
PA
I know right where you live, my Dad lives in San Clemente, so I know the climate well over there [Smile] I would probably change it every 6 months or something for good measure, it won't harm anything to sit in there if its a decent lube. As little as you drive it, the oil shouldn't degrade much.
 
Messages
3,321
Location
Bolivia
I'm a firm believer in the 6 months or 6000 km rule. Whichever vehicle I leave at my other office/home city will see 100 km a day for the 1 week to 3 week stays that I do there 6 to 8 times a year. But might well sit still with someone starting it for a few minutes so the battery won't die in the 4 to 12 weeks that I don't visit. Last year I analized the oil at 7 months/4000 km and found high lead (52 ppm). I'm not passing 6 months again. (99 4Runner turbo diesel)
 

timzak

Thread starter
Messages
372
Location
Rancho Cucamonga, CA
Thanks again for all the suggestions. Currently, the Stang has 5qts of MaxLife 10W-30. Is that quality enough to leave in for a year? I seem to be getting two sets of responses: once a year, and twice a year, with one or two guys suggesting every 3 months regardless. Right now, I am leaning towards twice a year (was last changed in April, so I'd do my next change in October, with about 1000 miles on the oil).
 

Patman

Staff member
Messages
21,989
Location
Oakville, Ontario
If you really want to know for sure, do this, run the oil for four months, then do an oil analysis on it. If it looks good, go to 6 months on the next interval, and analyze again. Keep going up by 2 months each time until you reach your comfort zone. Otherwise, all we are doing here is speculating.
 
Messages
951
Location
Loveland, Colorado
Patman, How 'bout he changes it at 6mos (like he was planning to do anyway) & runs a UOA on that? Then he can decide if he wants to go to 12mos based on that data? If he decides to go to 12mos, he then runs a 2nd UOA when he changes that oil & looks at that data. If it looks either good or trashed at 12mos, it's a no-brainer. That way, he's only running two UOAs & getting all the data he needs for his choice of either once or twice a year changes. Make sense?
 
Top