Oil change interval?

[Jayco-noslide]

Recently bought a used Ford Focus from the dealer. Re: the sticker on the windshield, I asked, "Do you use a 3000 or 5000 suggested oil change interval. He answered, they used 5000 for awhile but got so much uproar from customers, they went back to 3000. I'm thinking, why let old fashioned uninformed customers determine this and waste all that oil and money. There's no evidence to suggest that we can't go 5000 miles and well over with oil. In fact the company generated manuals recommend it, with a few possible exceptions. I'm not so sure about a motor home, which is always under a load? I still think I can safely go at least 5000 with my Ford V-10? Opinions welcomed but let's hear some fact evidence back-up.
Remember when everyone thought it should be 1000 but most of you probably aren't old enough.

[boogie_4wheel]

I'll play this game...

My last truck ('97 GMC K1500) 244k miles when I sold it. Rotella syn-blend 7500mi intervals. I pulled the heads at 207k; cylinder walls looked excellent, no scoring or ridge.

Current beater ('05 Ford Escape) 278k miles. Valvoline convential at ~7500mi intervals. I replaced the valve cover gaskets at 241k. No buildup on the valvetrain at all.

My Cummins is on Rotella Syn with 1yr or 10k mile intervals (whichever comes first). I submitted an oil analysis after 7800mi; TBN was 8.5, and suggested to run 10k intervals.

Everything I own gets Wix or Napa Gold filters, including the bikes. The only thing that gets 'frequent' oil changes is my air cooled XR650 since it regularly sees oil temps above 250.

[wnjj]

wildtoad wrote:
You can’t prove a negative event. Just because you have not had an OIL caused failure does not mean it’s due to changing more often than necessary. It can’t hurt to change it frequently but no way to show it is the reason for such longevity. You can however prove that not changing it was the cause of a given issue.

For me it’s the greater of 5k miles or what the manual says. Oils are too good now to change any sooner.

x2. My uncle's '72 Chevy 350 has over 400k miles and he is terrible about regular service. Sometimes the oil isn't on the stick. The only thing done to the engine was the timing chain when the original nylon-toothed sprocket came apart at ~220k.

[wildtoad]

You can’t prove a negative event. Just because you have not had an OIL caused failure does not mean it’s due to changing more often than necessary. It can’t hurt to change it frequently but no way to show it is the reason for such longevity. You can however prove that not changing it was the cause of a given issue.

For me it’s the greater of 5k miles or what the manual says. Oils are too good now to change any sooner.

[fj12ryder]

Eric&Lisa wrote:
Daily driver #1: 306k miles.
Daily driver #2: 296k miles.

Both on original motors, never been rebuilt. I am religious about doing oil changes every 1500-2k miles. I do them myself, less than $25 in oil + filter, and about 20 minutes of work.

Take it for what it is worth. That is my personal experience, and I am sticking with it.

-Eric

Wow, think of the money you could have saved if you'd have done your oil changes at normal intervals. You could have enough money to buy a whole engine if necessary, which it wouldn't be, over $7500 dollars in oil changes.

[Eric_Lisa]

fj12ryder wrote:
Just because the dealer tells you that is no reason to think it's true......

The dealer wants you back in the door right after you paid off that 60 month loan, when your car is pushing 100k miles and is starting to cause small problems due to limited maintenance. They will get you right over to the deal desk and get you started on a new 60 month loan.

Don't think for a second that what is in your best interest is also in the dealer's best interest!!!!

[Eric_Lisa]

Daily driver #1: 306k miles.
Daily driver #2: 296k miles.

Both on original motors, never been rebuilt. I am religious about doing oil changes every 1500-2k miles. I do them myself, less than $25 in oil + filter, and about 20 minutes of work.

Take it for what it is worth. That is my personal experience, and I am sticking with it.

-Eric

[afidel]

Ford fleet service interval for E450 with V10 and towing (motorhome would be similar in engine load to towing) says oil every 3k miles and transmission change every 30k miles with a check at 15k miles.

[2oldman]

Sometimes people just do what they feel is best - or they heard some scare story that convinces them. Hard to overcome that with reason.

[Tom_N]

Quote a manufacture's manual that shows a different oil change interval for dino and synthetic.

[ppine]

Synthetic oil continues to get better. It does not wear out it just gets dirty. You can change filters and keep going. Lab analysis shows that synthetic is often good for 10,000-15,000 miles or more.

Micro-filtration will be the next technology to go main stream.

[fj12ryder]

Just because the dealer tells you that is no reason to think it's true. It's very likely that they want to do 3000 mile oil changes and telling you it's what people wants makes it more likely you'll go along with it.

With modern oil and modern engines, 5000 miles is as short as I would go. 3000 mile oil change intervals is just wasteful. Both of oil and your money.

[BB_TX]

What the owner’s manual says. Over 50 yrs and around 1.5 million miles and I have only used good quality regular (not synthetic) oil and have always followed the owner’s manual. Have never had an engine fail or even need any oil added between changes. One of those engines over 200,000 miles and several well over 100,000.

Why would I take some random person’s opinion over the manufacturer’s recommendation?

[dodge_guy]

I still do 3k on regular oil and 4K on synthetic.
I’ve been a tech for 30 years. I have replaced engines that show what happens when you go by the manuf. interval. 5k isn’t a crazy amount of time to go if it’s synthetic.

Now I have to ask......why do people go strictly by the manual when doing maintenance, not doing anything more than what’s printed! but when it comes to tow ratings they say don’t go by the owners manual. And go 20-30% less. Hmmm.

[garyemunson]

I go 7K with my V10 always using full synthetic. When I drain at 7K, it look almost like when I put it in.