Recent Topics
'05 Scion Xa
by womcat
12/19/14 06:57 PM
1 year OCI - When to change?
by camrydriver111
12/19/14 06:32 PM
What Airtex, Autolite, Fram and Prestone all hav?
by chad8
12/19/14 06:12 PM
ODO fraud. What would you do about it?
by friendly_jacek
12/19/14 05:24 PM
Toyota 90915-YZZG1 Made in the USA
by Tmiller3063
12/19/14 04:17 PM
Mystery oil loss
by Mar57
12/19/14 04:05 PM
Brand new VW 2.0T- Castrol 0w40 ok?
by gijello
12/19/14 03:51 PM
An opinion please.
by hank55
12/19/14 03:50 PM
fixed the dreaded rust!
by Robertslowpoke
12/19/14 03:41 PM
Reading the dipstick on a GM 4.3l V6
by Sierra048
12/19/14 03:22 PM
Silk browser alternative
by possum328
12/19/14 01:53 PM
John Deer LA 105 Oil Recomendation
by AndySantoro
12/19/14 01:35 PM
Newest Members
AggiePreacher, novcz, SCFarmer, LumpOfCoal, carguymitch
52229 Registered Users
Who's Online
107 registered (147_Grain, 1034, 01rangerxl, 2010_FX4, 2009Edge, aa1986, 8 invisible), 1331 Guests and 188 Spiders online.
Key: Admin, Global Mod, Mod
Forum Stats
52229 Members
66 Forums
223667 Topics
3546648 Posts

Max Online: 2862 @ 07/07/14 03:10 PM
Donate to BITOG
Topic Options
#1585030 - 08/31/09 09:09 PM Oil change interval: time vs. mileage, low mileage
Lightsilver Offline


Registered: 04/15/08
Posts: 33
Loc: Midwest, USA
Quote:
The conventional wisdom is to change the oil every six months normally, and up to a year on a high quality synthetic.


I'm curious: why the change interval at six months?

The reason I ask is that my elderly mother only drives her 1999 Olds Cutlass, (with 52K on it), less than 100 miles a week, the past few years.

The dealership had her convinced to change the oil every 3 months, so she was changing the oil with less than 1200 miles on it.

I told her to change it at 3000 miles. Depending on how much she drives, she could easily exceed 6 months.

I figured that while her car is sitting in her garage, (which it does, several days every week) the oil isn't breaking down...or is it?

I do have her 'trained' to take her car out on the freeway, and drive it for about 5 to 7 miles, rather than just driving the 1 mile to church, or the library, etc., and back. So, she's not doing too much 'short trip' driving. She really doesn't understand why, but she does it.

I check her oil, and it is still quite 'clean' looking, on the dipstick, and on a white paper towel, at around 3000 miles.

I do not know what brand of oil the dealership is using; I'm sure it's dino oil.

So what's the 'conventional' wisdom for dino oil: change at less than 3000 miles, if the time exceeds 6 months?

TIA!

Top
#1585046 - 08/31/09 09:21 PM Re: Oil change interval: time vs. mileage, low mileage [Re: Lightsilver]
Gary Allan Offline


Registered: 09/28/02
Posts: 39806
Loc: Pottstown, PA
Time (years) will destroy that car before anything else. Most of the OEM recommendations are for daily drivers. I wouldn't go to the trouble of doing the highway thing. It's just spending money on gas.

I really don't see a reason why 2500/6months would be too long.
_________________________
http://lube-direct.com/gallan/

Top
#1585058 - 08/31/09 09:28 PM Re: Oil change interval: time vs. mileage, low mileage [Re: Lightsilver]
Corvette Owner Offline


Registered: 01/22/03
Posts: 1632
Loc: Waldorf, Maryland
The 1 mile drive is the worst scenario for oil. Short drives, where the oil temperature does not get high enough to "burn off" moisture will wear down oil (through acids), dilute it, and increase engine wear.

It would be interesting to do a TBN (and used oil analysis) on your mother's car's oil. That is really the only way of knowing what condition the oil is in.

Generally, it is accepted that dino oil is good for 6 months and 5,000 miles. Synthetic oil is good for 1 year and 7,500 miles. That is conservative, you can add 2,500 miles to those figures for "good oil".
_________________________
Vehicles:
98 Corvette
06 Murano
96 Chevy Van (Custom Conversion)
14 Chevy Impala
10 Starcraft Boat
13 Buick Enclave

Top
#1585130 - 08/31/09 10:14 PM Re: Oil change interval: time vs. mileage, low mileage [Re: Corvette Owner]
daves87rs Offline


Registered: 02/23/09
Posts: 13647
Loc: Michigan
When I've parked my other Cav for weather's sake (it was a nasty winter), I maybe drove it 100 miles in nearly three months. When the weather was decent, I took it for long drives to warm it up good.

I plan on driving it more this winter (weather permitting), and keeping the Napa syn in there until early spring. (about 10 months) It might change if I drive it more....
_________________________
“The Only Thing Necessary for the Triumph of Evil is that Good Men Do Nothing.”

Top