How many miles for a 4 cyl doing almost exclusively highway miles?
Vehicle will have 5w20 synthetic.

What does mfg. recommend? I change mine(v8) at 5K, synthetic.

Depends on how many miles and how long it takes to get there. On my 2012 Tundra, we use the synthetic oil and it usually takes about 3 months to put on 10,000 miles before changing oil. If we weren't putting the miles on that fast, I would change at 6-month intervals, regardless of mileage. In the 2005 Tacoma, I change oil and filters at the recommended interval of 5,000 miles using 5W-30 Rotella, even if it hits 5,000 in less than two months (which has happened a number of times in its 258,000+ mile life).

Most of these miles are obviously highway miles, the majority of which are put on in what we would call "warm weather". We do have a lot of dust to contend with at different times of the year, so air filters get changed at 10K no matter what.

In the grand scheme of things, oil is cheap. I go 7500 miles on both a 4cy and 8cyl with Mobil 1 and a good filter. Many new vehicles are coming with 10,000 mile intervals now. My last BMW, Toyota, and Volvo all had 10K interval recommended from the factory. Don't go over 10K or one year and you will be fine.

That being said, if you know you are getting contaminants like gas blow by then change more often.

Good post.

Not referring to routine maintenance intervals, but more of a maximum one-time interval.

Mobil 1 extended is guaranteed for 15K. This is about a trip of somewhere between 10K and 15K in about 2 - 2 1/2 months this summer. Looking to avoid oil change until the vehicle gets home. Don't want it done on the road at Jippy Lube.

I normally use dino oil and change at 5K. Using synthetic it seems reasonable to be able to go at least twice that with normal (not severe) conditions.

Synthetic is good for 10 to 15k but a filter change half way through might be advisable. The old 3k standard that many still go by is a total waste of time and oil. All of the newer cars can go twice that or farther even in the worst conditions.

For your trip, Mobile 1 is a good choice but you might find a Jiffy Lube handy for a filter change before you come home.

Mobil 1 EP filters match the mileage guarantee of their EP oil.

Oil analysis will tell you what is good. The rest is just guessing..

But with good filters and oil, I wouldn't be afraid to go 10,000 miles.

I ran Mobil 1 5w20 in several vehicles and changed oil about every 10,000 miles.

Worked fine on my Chevy S10 that I put 196,000 miles on before selling.

I buy Mobil1 from Costco at 26$ per 6 qts on sale. I get OEM Toyota filters for cheap and change them both at 5k in my 2002 tundra. Oil is very cheap, even if changed "too" soon. I also run Mobil1 in the transmission.

A simple oil analysis will tell you exactly what condition your oil is in. If it is in good shape, don't change it.

I know of one semi tractor that is running on 340,000 miles with only filter changes (including an aftermarket bypass filter) and make-up oil added. That's right, 340,000 miles without an oil change.

Compare that to PM's at every 15,000 miles at $290 each, and a $30 oil analysis (such as Titan labs) pays for itself pretty quick.

I've never personally known of anyone that had an oil related failure at under 200,000 unless they ran out of oil. Lots of those guys/gals changed once or twice a year at most.

I think the most important thing is to just keep oil in it.

I've seen multiple oil related failures, as early as 65k miles in one case, many before 100k. Of course, they are uncommon, but since I'm in the repair business, and have 5-15 cars a day through my shop, it's not surprising.

They are mostly failures due to a lack of oil changes, not the fault of the oil itself. Everything from seized cam bearings, to variable valve timing mechanisms, to oil pressure loss as a result of contamination and sludge formation. Synthetics are not immune to this, or at least Class 3 synthetics like Castrol. Don't see it much with Mobil 1 though. Had more than a few that are subjected to the 20-25k change intervals, have oil filters that are removed in pieces from the canisters, and when valve covers are removed, are so full of sludge that the only bare metal visible are the cam lobes. Everything else is covered in a thick layer of gritty goop.

You are better off to change the filter more often than the oil.

If you had to do it this way, I'd screw on a new filter 1/2 way through, & top-off to "FULL" on the dipstick.

What if you figure out your route, then ask us "trusted members" to recommend a top-notch mechanic at waypoints along your route? No Jippy Lubes stops, & a great excuse to share a beverage while your car is serviced.

We could talk about flouride use among Remington-shooting Masons...

FC

Funny stuff and fixed!

I've decided that it will be fine with Mobil 1 EP (15,000 mile oil) until it gets back here. When the vehicle is at relatives' places in America, I'll probably arrange for a filter change and top off.

In looking for info on specs (vehicle not here at the time) I found out the timing belt is reco'd to be changed every 60K and it had 75 on the clock. Got that done today. Looking at the old belts, I'm happy about that!

Fluids tomorrow.

Thanks for the replies guys.

Freeway miles are easy on an engine and oil. It's the frequent start stop city stuff where the engine never gets up to temp where you have to worry about the oil sludging up.

I wouldn't sweat going 15k with mobil 1. We got ~230k on the wagon before the boy decided to play rally driver on an icy road last winter. Regular intervals were 10k, a few times stretched to 12+k and while the engine burned some oil and seemed to be a little down on power from age, never an oil failure.

I've been running 10-12k intervals on both my truck and wife's car with Amsoil with no issues. I've sent a sample off to Blackstone and every time they've told me I could go longer if I wanted.

I've got 345,000 on a Toyota Camry 4 cylinder, that has seen 20 and 25,000 mile oil changes its entire life...Mobil One exclusively, with a filter change every 5 K....never been apart and the valve cover off, and its still pretty darn clean, with no sludge accumulation...

then an 88 4Runner, with the 2200RE under the hood with 535K on it... same thing... 20 or 25,000 mile oil changes with Mobil One, or Mobil Delvac One...filters every 5K... no sludge on that one either.....

bought a used Honda Prelude with a highly sludged up engine for cheap once... that was Pennzoil Sludged up.... thought I'd do an experiment since I got it cheap enough...put Mobil One 0W30 in it, and changing the filter every 5K, and then just run it until it blew up...

Put 40K with no oil change on it... friend got divorced and needed a car and wanted it so bad, he badgered me until I agreed to let him have it... changed the oil, tuned it etc before letting it go... but a look under the valve cover by removing it.. all that Pennzoil Sludge was long gone...in 40K, Mobil One cleaned that crap up and took it out thru the oil filters...

so I'd bet you're going to do just fine there Ironbender...

My thinking too, hence that detail in my OP.





Welcome to my world!



Just did an oil change and this motor has not used any oil in 5K. I may arrange a filter change when my driver is at a relative's place.

Thanks again fellers.

What are the odds?

I have used Mobil-1 in all of my gasoline fueled vehicles for over thirty-five years and try to change it at 6,000 mile intervals. Most of those vehicles have run over 150,000 miles and all but one were still running strong when I sold or traded them.

I figure that oil is cheap insurance, particularly in a high mileage vehicle that might not be worth repairing if it incurred a major engine failure. I have Wal-Mart Tire & Lube Centers (TLCs) do my oil changes, but I ALWAYS WATCH THEM to insure that they put the proper oil in.

I use Mobil-1 High Mileage 5W-30 during the colder half of the year, November thru April, and 10W-30 during the other, warmer, six months.

If your vehicle is going to be heavily loaded and/or you're going to be driving a lot of steep grades, I would opt to change oil sooner, due to the load on the small engine.

5-6K and plain ol' dino oil and filter.

That's my SOP, but different from the situation that I was referring to above.

Thanks, all. The vehicle is now in northern YT.

I do 1 year or 5000 miles.

in my 07 civic i change the dino oil when the light on the dash board says "change oil". i think its 7500. this method has worked for about 20 years, 350k miles and 2 civics.