More of just a statement shrp just in case he doesn't drive it much :-)

 

I've been using castrol high-milage part synthetic (what my dad used before he gave it to me). For a while I changed it every 3000mi or 3 months because It was only being driven 4 miles to school and back everyday (while I was still in high school). Now I drive about 20 miles every other day (half highway and half city), since then I've been changing it every 4500-5000 miles or every 5 months.

The right interval for you is going to depend alot on how you drive it (how far, etc...)

 

good advice, by checking the oil u can really tell when your ready for an oil change.

 

ok just checked my owners manual for 'normal' operation they recommend a 7500 mile oil change interval with dino oil, for 'severe' (fleet or off-road or towing) operation they recommend 3000 mile oil change interval do with this information as you please

 

Thanks shrp, I Will add that i chek my oil nearly everyday, and I have almost 211,000 on my ticker, after about 2500 miles, my oil is very dark and getting a little runny, so IMO I think 3000 is better for me. Now with synthetics, they last forever it seems so I would say that it's really up to each person when they feel is the correct time to change. 7500 miles just seems high to me, even with a motor with 20,000 miles

 

The manual may say every 7000 miles but ill bet it also says under regular driving conditions and unfortunately 90% of people do not drive the way manufacturers define regular driving conditions so the 7000 mile recomendation in the manual a bit too high for regular oil. Majority of people fall into harsh driving conditions as defined by manufacturers amazingly just driving around town would fall into this category and I beleive the oil change intervals most manufacturers would refinement for this would be around 3000 or 4000 miles. There's a reason why when you get your oil changed somewhere they stick a sticker on your window reminding you when the 3000 miles is up. It's not because they want to scam you and get you to come in more frequently its because that's about when most regular oils start to degrade and break up. For synthetic oils 7000 is a pretty safe bet if your running a good synthetic brand but 10,000 is about the limit for synthetics before they start to break up. To answer the question I would say change the oil in it at least once a year or every 7000 since your using a synthetic.

 

Just my $.02, but using synthetic might be the trick considering the OP's mileage on the vehicle. Organic oil tends to sludge when it's in a vehicle/motor which doesn't even warm up to full operating temp often enough to prevent sludging, plus the occasional change interval would exacerbate the issue.

I've seen junkyard motors which wouldn't run which simply had too much sludge in the lifters/webbing area of the block/lower end, but once they were pulled apart, cleaned up, and put back together ran fine. 'Course in this case we're trying to prevent that.

One Mopar motor I tore apart for a friend two years ago, a 5.2L Magnum about '98 vintage, had sludging issues because he rarely changed the oil. Literally there was over 3/8" of sludge down in the lifter valley/webbing of the block. Cleaned it up then used that stuff I'll never remember the name of to clean it out after buttoning everything back up, let it run up to operating temp, then changed the oil. The stuff that came out was like tar. Props to the Mopar engineers who designed these motors as they knew they'd be abused, and designed accordingly (something they've done since the founding of the corporation). Try doing that with a Phord.

 

For gods sake do I have to go through this again?....Really??????


Fully synthetic oil, meaning a "Polly base" structure like Mobil One FS should be replaced after 7500 miles under normal extended conditions (hwy conditions) like straight highway mileage and such. Time line is 1 time per year at least.

Now under normal hwy use, yes meaning the you, the guy who likes to play, likes to tow some what, the guy who city drives, the guy who does the day to day grind Highway mileage, yea you! Replace yours every 5000 miles or at least twice yearly because you should be putting on about 15k yearly. If you put on less then at least once yearly, this is what I do.

The next, the 3000 mile "Sever Duty" use, yea I'm talkin about the hard core user, the dusty road/off road user, the guy who tows each day, plays off road and on, extended idle, the guy who makes the chassis and engine beg, yea that guy. Replace yours every 3000 miles or 3 times yearly.

Other lower synthetics including Hydra-Cracks are different, I'm talking about Mobil One FS here.

The main reason the time line is there is because of 2 things in reality.

1. Extended idle, yea people like to idle their engine without moving meaning no mileage recorded yet the engine is still moving. So those people waiting to pick kids up at school, with engine running but no mileage placed means the oil still need replaced, got it?

2. The hard core guy that tows like a freight train, yea the guy that tows that large load from this 1/4 mile post to that post, the guy that works his ride.


So meaning read the itinerary, there are 3 distinct people, people that don't work it. People that are the norm, so to speak. And finally the hard core guy.


Mainly the reason the time line is there is because of acidic residue from the every day use of the motor, and the durability of what the driver is using.

 

Using an oil like Mobil 1 Extended Performance, which is rated for 15,000 mile oil changes then changing it every 3000 is pointless, unless you have issues or something. I change mine every 10k with no problems. The new Porsche's say 12k mile oil change interval. And thats in a high performance engine. 3000k miles is WAY outdated. BTW I switched to synthetics with 200k miles on the clock and had no problems. No leaks. Nothing. The "Dont use Synthetic in high mileage vehicles" theory is a myth to. If you already have leaks with regular Dino oil, your gonna have leaks with synthetics.

 

It's more than just a myth, bought a vehicle a few years back, owner had just done a Dino oil change, so I switched it at 3,000 to a Mobil one full synthetic, and gained leaks. Valve covers, rear main, and timing cover. If there were no leaks before, then why all the sudden leaks after I switched? You can't call it 100% yes or no with that, seems like it depends in the motor and how good the seals are