OIl Change Intervals for my Specific Vehicles

[soundwavefd]

I was just looking for some advice for oil change intervals for the two cars I own:

1. Subaru Impreza WRX (2.0L Turbo Boxer). I use Shell Rotella T6 5W-40 Synthtic. The car has 53,000 miles and only sees about 3-4 k miles a year.

2. 1993 Mazda RX-7 (1.3L Rotary Twin Turbo). I use Castrol GTX 10W-30 Conventional. The car is a Sunday driver, has 19,000 miles and sees about 1.5 k miles a year.

Any help would be appreciated.

Thanks,
Drew

 

[randomhero439]

Wow you dont drive at all! As for the subaru, do like once a year.
As for the Mazda, do once a year or maybe every 6 months

Nice cars btw

 

[beast3300]

If it was me I would do both once a year. Before driving them for that new year, I would drive them to attain full operating temp and change earls. Then you should be good to go!

 

[jrtribology]

I have never went more than 3000 miles on any oil, I've always changed at 3000 or 6 months which ever came first. I've changed oil every 3000 miles an used Mobil 1 5w30 or 10w40 My mothers 1997 Lexus ES300 for (as of this post; just changed it an hour ago) 110,507 miles and it has never burned or leaked any oil. Something I never hear anyone talk about is cooling system cleaning and changing. You can change your oil every day of the week and use a top name brand synthetic, but if a cooling system is accumulating rust from never being taken care of-all efforts are wasted

 

[fauxchemist]

Not sure how cooling system relates to motor oil. How lack of cooling system maintenance reflects on oil efforts. Anyways, I have 400,000 on my all original Jeep and have never cared about cooling. Only reason that stuff has even been messed with is radiator replaced four times, same problem every time(plastic endcaps cracking)and replaced fan clutch twice.

 

[randomhero439]

Originally Posted By: jrtribology
I have never went more than 3000 miles on any oil, I've always changed at 3000 or 6 months which ever came first. I've changed oil every 3000 miles an used Mobil 1 5w30 or 10w40 My mothers 1997 Lexus ES300 for (as of this post; just changed it an hour ago) 110,507 miles and it has never burned or leaked any oil.


Such a waste of oil to change every 3k. My routine is: Use severe interval with conventional, and the normal interval with synthetic.

When i autocross my Accord, i change it every 3750 (severe interval).

 

[jrtribology]

However, the 2000 Buick LeSabre limited that I've inherited from my grandfather has about 32,000 miles and i swear burns 1 quart of oil very 500 to 2000 miles, and it is burning it because i can't find any detectable leak or see any leaked lubricants on the ground below it. My Grandfather claims to have had the oil on the cars engine changed every 3 months regardless of mileage-it just doesn't make any sense, unless the Buick dealership had been ripping him off. By there own admission they had never flushed/cleaned/ and changed antifreeze in the entire time he owned the car. If they cared so much about my grandfather then why didn't they convince him to let them do it for him once every 6 months to a year. Oh yeah the car gets about 10 miles a gallon

When I went to the dealership they wanted $53 dollars to changed the oil even though I provided the oil and the filter !

 

[1999nick]

Originally Posted By: jrtribology
I have never went more than 3000 miles on any oil, I've always changed at 3000 or 6 months which ever came first. I've changed oil every 3000 miles an used Mobil 1 5w30 or 10w40 My mothers 1997 Lexus ES300 for (as of this post; just changed it an hour ago) 110,507 miles and it has never burned or leaked any oil. Something I never hear anyone talk about is cooling system cleaning and changing. You can change your oil every day of the week and use a top name brand synthetic, but if a cooling system is accumulating rust from never being taken care of-all efforts are wasted
I quit doing 3000 mile OCI's back in the late 60's or early 70's when most cars began calling for 7500 mile OCI's with normal driving. I usually did 5,000 mile OCI's as a compromise between the 3, 000 mile severe service interval, and the 7500 mile normal service interval.

When Mobil 1 was introduced in the latter part of the 1970's, I began to use it, and have never looked back. I use it as it was originally intended: one year or 25,000 mile OCI's. My usual OCI, before I retired back in 2001, was 18,000 t0 20,000 miles. Since then, my usual OCI has been about 9,000 miles. Always had a quiet engine, and never an engine problem. My vehicles would usually use about 2 or 3 quarts of oil in 20,000 miles. My present vehicle, a 2005 Pathfinder. uses no oil in a 9,000 mile OCI.

 

[Clevy]

Originally Posted By: jrtribology
However, the 2000 Buick LeSabre limited that I've inherited from my grandfather has about 32,000 miles and i swear burns 1 quart of oil very 500 to 2000 miles, and it is burning it because i can't find any detectable leak or see any leaked lubricants on the ground below it. My Grandfather claims to have had the oil on the cars engine changed every 3 months regardless of mileage-it just doesn't make any sense, unless the Buick dealership had been ripping him off. By there own admission they had never flushed/cleaned/ and changed antifreeze in the entire time he owned the car. If they cared so much about my grandfather then why didn't they convince him to let them do it for him once every 6 months to a year. Oh yeah the car gets about 10 miles a gallon

When I went to the dealership they wanted $53 dollars to changed the oil even though I provided the oil and the filter !

That car needs a really good hot run. I'd bet from lack of use the ring packs are coked up,the injectors clogged from never having to pump a lot of fuel etc.
First off compression check the cylinders. Then find an additive that can clean the ring packs. And run the car hard. Put some kind of pea cleaner in the fuel,for a few tanks and don't be shy with the throttle.
I respect dnewton's opinion and posts. He declared that arx helped the compression in an engine he had experience with. Now if the engine isn't sludged I wouldn't use a solvent type flush in your engine however there are many members who have used kreen and had good results.
Pick your poison,you've not really got much too lose at 10mpg in that car.

 

[jrtribology]

That's very interesting what would you recommend for taking care of stuck or coked piston rings I read in an old thread somebody wanted to use MMO-marvel mystery oil. Also I know a good shop near me that cleans fuel injectors. What is "pea cleaner" ???

Strangely enough the car is able to get about 26 mpg at steady highway speeds but goes down to about 10 to 12 mpg in stop and go traffic