Oil change....how often

mercury
grandmarquis
oil-changes

#1

Hi everyone, my mom has a 1993 Grandmarquis, it only has 32,000 miles. She only uses it to go to the store and back. We usually only change the oil every 6 months. Someone told us 6 months ago to come back every 4 months because she doesn’t drive much and because of that the oil doesn’t get hot enough to burn off the impurities. Well we went again yesterday and they told us not to come back for a year because we don’t drive much…WTH, who is right?


#2

It depends on how far it is to the store and back.

If the engine doesn’t get up to full operating temperature, moisture in crankcase doesn’t get driven out. And that’s not good for the engine.

If this is the case, all that needs to be done is take the vehicle for a short drive every so often so engine reaches operating temperature to drive the moisture out.

Then change the oil every six months.

Tester


#3

I’d agree, 6 months or 3000 miles I think would be fine.


#4

Except for the reality that the OP’s mother apparently drives ~1,300 miles per year.

Yes, the person who stated “every 4 months” for oil changes on this car was correct.


#5

I dunno, an oil change at 4-500 miles seems a little unnecessary. Although I used to change oil on my Olds once a year and usually had 7-15 miles on it for the year. That might have been excessive but its in car heaven now.


#6

32,000 miles in 25 years with oil changes every 6 months…

…hmm… Since it’s still “on the road,” I’d just keep on doing what you’re doing! Why change now?

For the sake of the exhaust system integrity though, I’d follow Tester’s advice and get this beauty up to operating temperature regularly.

CSA


#7

Oil & filter every 6 months, and if possible figure a way the car gets a long enough drive that the dash engine coolant temp gauge reaches the midway point. Do that at least once every couple weeks. If that simply isn’t possible to do, just changing the oil will do most of what’s needed. I expect you already know that a 25 year old car is nearing the end of its service life, so be on the lookout for a replacement.


#8

If there’s no rust damage there’s no reason the car is near the end of its service life…especially at an average of 1,300 miles a year…If it were my car, I’d change out all of the fluids next time an oil change is done and maybe new tires depending on how old they are…otherwise this car is probably going to be good to go for a long time


#9

As a diy’er that’s what I’d do too. But I get the sense the OP isn’t asking from a diy’er perspective, and the problem on an older car like that replacement parts may become time consuming to find, and the price to do a repair will be considerably more than the car is worth.


#10

I guess that ridiculous statement means that George is going car and truck shopping.


#11

I recall the “Normal Driving” service interval for that car calls for changing the oil every 6000 miles, and the “Severe Service” interval cuts it to 3000 miles.

Even with your severe service driving, your changing it every 6 months is more often than recommended.

I would stay with the 6 month schedule. Or if you take the car out every month for a good 1/2 hour drive, then extend the oil change to once per year.


#12

What does the owner’s manual say? Does it list this type of driving as severe service? Does it give the mileage and time interval for that case?


#13

Memorized rules are perhaps better than nothing. I believe when possible,use intelligence and common sense. My 2002 Sienna, sidelined due to Mexican import rules, had 222,000 miles on it. Fresh Mobil-1EP Twice in a year I went back, and drove it around a couple hundred miles, with plenty of warm up each time.

At this time, I do not plan to change the oil in the predictable future. The car is not shut off cold, and there is nothing contaminating the oil while the motor sits idle.

From everything I have read over the years, eventually there will be seals going bad somewhere on the car, and it will not be economical to repair. In the meantime, the oil in it will be the very last oil ever for that car.

Unless someone in the family wants it.

The car of OP is a different matter. It is not warmed up very often, but driven relatively often. Yes, change that oil often.


#14

Mom probably has the owner’s manual in the glove box. Do whatever it says for severe service. If money is a problem, do it once a year, but don’t go any longer.


#15

Thank you for your help


#16

I want to thank everyone for all their help. God bless


#17

Best of luck OP.


#18

You don’t need to change it but every year. The oil doesn’t break down that fast, moisture won’t hurt it but keep it to the 6 months interval as that has been your schedule forever.

Also I noted some people said the car isn’t worth fixing. But I can tell you that in a super duper worst case senario (engine over haul, air assembly, radiator replcement) $4000 is a whole lot cheaper than a $20,000.

Look up oil analysis and repair costs at a local mechanic to verify what I and others have said.
PS make sure to change the radiator coolant every 5 years as it protects the engine. (It’s 3-5 years on the recommendation)


#19

Now we’re back to cost benefit analysis of car repairs. True a $4000 repair is cheaper than a $20,000 car but that’s apples to oranges. The $20k gets you all new parts and you start over again at square one, not just with a new engine or trans. As one who repaired them too long maybe out of necessity. Just sayin’. I’ve heard it so many times though just had to chime in.


#20

This is an area where all you are likely to receive is anecdotes and ideas. No one really knows, although you can find good information.
The good news is that since this car has lasted so long, it’s probably been treated pretty well and whatever she is doing, she is probably doing better than most of the advice she will receive on how she is not doing something right. Advice is common; success is rare.
If you are concerned, I would do an internet search using GOOD sources like Edmunds or the manufacturer’s sites. You’ll find plenty of disagreement but also support for whatever seems reasonable to you.
Given the short distances she drives, well, yes, she is probably stressing things somewhat, but her mechanic probably knows the car better than we do. Six month oil changes should be fine. Theoretically, synthetic or semi-synthetic oils may tolerate contaminants better but they may leak more, too.
Sounds like her mechanic has been good about other critical areas, like changing brake and radiator fluids.
If she hasn’t driven the car at highway speeds for a while, it may be unsafe for her to do so.
Good luck.