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I was at Wal-Mart the other day and saw some Mobil 1 5W30 full synthetic motor oil claiming to be "guaranteed for 15,000 miles". It was $25 for the big 5 quart container. Granted my next oil change is still a way off (last change was 3 weeks ago at 94k miles, now have 94,600)
But if I were to purchase that oil (factory recommends 5W-30 for my 2003 Nissan Altima) claiming to be guaranteed for 15k, will I really be able to go that long without changing my oil? Or is that claim a bunch a bull and is a change every 2500-3000 miles still necessary?
I also live in Las Vegas, and its going to be extremely hot when my next change is due (mid July). Will that cange anything or is this oil really good for 15k?
I was at Wal-Mart the other day and saw some Mobil 1 5W30 full synthetic motor oil claiming to be "guaranteed for 15,000 miles". It was $25 for the big 5 quart container. Granted my next oil change is still a way off (last change was 3 weeks ago at 94k miles, now have 94,600)
But if I were to purchase that oil (factory recommends 5W-30 for my 2003 Nissan Altima) claiming to be guaranteed for 15k, will I really be able to go that long without changing my oil? Or is that claim a bunch a bull and is a change every 2500-3000 miles still necessary?
I also live in Las Vegas, and its going to be extremely hot when my next change is due (mid July). Will that cange anything or is this oil really good for 15k?
I'd stick with what the Owner Manual of the car states, not folklore or what's written on a bottle to try and sell it.
The only thing I'd want to mention to you is that you could use 10W-40 in Vegas, since it's so warm. Your Owners Manual also states that this is fine.
My garage man changes his own synthetic oil every 10,000 in his own vehicles, but he admits it should probably be done about 7-8,000. Check the sale flyers from your local auto parts stores, they will usually have a good brand of synthetic on sale for less than that, including a good quality oil filter. Don't use a cheap filter if you plan to run your synthetic more than about 5,000 miles. You could probably run your synthetic to 15K if you changed the filter every 5K, because your filter will still be doing the same work, no matter what kind of oil you are running through it, removing the same impurities and contamination.
Read the fine print and see what the guarantee really covers, under what terms, and make sure it's not 15,000 kilometers. It might just refund your $25 oil purchase if your engine blows. But Mobil-1 is pretty near the best oil you can get.
Even today's conventional oil will usually be fine for over 10K miles and syn oil longer. Drivers that have an excessive number of cold starts or extended periods of extremely high rpm may need changes more frequently but one year or 7-8K miles is plenty often.
Todays synthetic oils will easily go 10,000 miles between oil changes,there is a segment of autodom that will waste money and resources by thinking that if they change their oil at 3000 miles their engine will last longer,well with that logic it should last even longer if you change the oil every 500 miles its an old oil company marketing gimmick to get people to buy more oil, i think the same guy convinced many people that Super Deluxe hightest supreme gold top tier gasoline was better for your car than just plain old regular never mind that your car was probably designed to run on regular.
I'd at least stick with what your owners manual recommends which these days is around 7000 miles.
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Change intervals are Very dependent on particular vehicle engine and driving conditions. Newer engines are a lot 'cleaner' / uniform tolerances to run longer intervals.
I use 10,000 mile changes on synthetics for my road vehicles.
For city use, I change oil filter and add a fresh qt of synthetic @ 5000 miles and change oil at 10k (usually in fall, so engine can have fresh oil for winter).
For Las Vegas temps I would be running a 10w-40 or 15w-40 synthetic oil in most vehicles (I run VW's to semis) I have over 3 million fleet miles on my VW diesels alone, no problems with extended oil change intervals. You can have your oil tested for ~ $20. I would do it at 5k & 10k and look to see any difference (doubt you will find any change in oil properties or contaminants until 20k+ in a healthy engine under normal service). If off road use or towing heavy and hot you may see some oil degradation earlier.
BTW, there are some better choices than Mobil 1 for synthetics (some of which WaMart carries). That said, Mobil 1 gave me excellent service in 2 older vehicles that went a combined mileage of 550K. On one truck (lots of heavy towing) @ 320k I pulled the heads to do valves, and cylinders were in great shape, still had some factory honing cross hatch and no ring grooves. This one had been using 20w50 Mobil 1 all its life. Of more importance is the use of auxiliary coolers and synthetic oil in automatic transmissions (they are far more troublesome in high heat conditions)
I typically use Amsoil, and buy as a commercial account. I am not a dealer, nor a drum beater, but they have a complete line of lubricants (which is important when maintaining a fleet with various needs)
I was at Wal-Mart the other day and saw some Mobil 1 5W30 full synthetic motor oil claiming to be "guaranteed for 15,000 miles". It was $25 for the big 5 quart container. Granted my next oil change is still a way off (last change was 3 weeks ago at 94k miles, now have 94,600)
But if I were to purchase that oil (factory recommends 5W-30 for my 2003 Nissan Altima) claiming to be guaranteed for 15k, will I really be able to go that long without changing my oil? Or is that claim a bunch a bull and is a change every 2500-3000 miles still necessary?
I also live in Las Vegas, and its going to be extremely hot when my next change is due (mid July). Will that cange anything or is this oil really good for 15k?
Back in the late 80's early 90's we did test to see how well syn did compared to mineral oil. The long drain times were found to be valid ONLY IF THE OIL FILTER WAS CHANGED AT NORMAL INTERVAL THEN A QUART OF SYN ADDED BACK ! NO FILTER WILL LAST MUCH PAST 6,000 MILES RELIABLY.
There is also the finding that syn will cause an older engine to start burning oil due to extreme cleaning of the carbon deposits in an older engine. We found that changing over to syn past 1,000 hours or 50,000 miles to be not recommended due to the extreme carbon removal.
Short answer is NO.. Synthetic oil will not last 15K miles in a car that does any kind of stop and go city driving. I've pulled and rebuilt more motors than I can count from people believing they can run extended miles (12-15K) simply because they're running synthetic.
Having sent off numerous test for customers over the years I've learned that most petroleum based oils are good for 4-5K miles before they effectively lose all ability to protect. Synthetics break down around 6-7K miles. Obviously this all depends on the condition of the motor and your driving style.
Long and short of it... If you do any kind of city driving then change dino oil at 3K and synthetic oil at 5K.. If you do highway only then I wouldn't be concerned with doing 4K for Dino and 6K for synthetic.
If not you will be visiting a mechanic before it's time.. You don't want to see the oil that come out of a motor after 15K miles...
I change motor oil on all my vehicles (but one) at 10k miles with synthetic oil (Mobil1, Valvoline, Castrol, Redline, and lately Amsoil). The filter is changed at 5k-mile interval. Never oil-related engine problem. If you are unsure whether you can go 15k miles, you can always take a sample (eg. at 5k and maybe at 10k mile) and send it to a laboratory to be analyzed for a minimal fee. From here you can determine a safe oil change interval for certain oil, you are looking for Total Base Number (TBN). The analysis also detects levels of metals, other liquids, and debris which can be used to determine the state of your engine.
I was at Wal-Mart the other day and saw some Mobil 1 5W30 full synthetic motor oil claiming to be "guaranteed for 15,000 miles". It was $25 for the big 5 quart container. Granted my next oil change is still a way off (last change was 3 weeks ago at 94k miles, now have 94,600)
But if I were to purchase that oil (factory recommends 5W-30 for my 2003 Nissan Altima) claiming to be guaranteed for 15k, will I really be able to go that long without changing my oil? Or is that claim a bunch a bull and is a change every 2500-3000 miles still necessary?
I also live in Las Vegas, and its going to be extremely hot when my next change is due (mid July). Will that cange anything or is this oil really good for 15k?
The one thing I will say is unless you drive like a grandma, in high heat conditoins if you are going to use a 5-30, you are better off with a sythetic.
Best oil change interval is a complicated question, but for most cars since the 1980s you can in general go 5000 miles or more before needing a change.
A simple test to see if the dispersant package in the oil is depleted is to put a drop of oil on some filter paper like a coffee filter. If it makes a "bullseye" the dispersant, typically the first additive to deplete, is still good, assuming you have some miles on the oil. If the dispersant is depleted, you will have more soot etc. in the center of the spot.
Of course if you want to get serious, you need to send a sample of the oil to an analysis lab, neither as hard or expensive as it sounds, any Caterpillar dealer will have oil analysis available.
Noria has a good book on picking out an oil and filter if you are interested enough to read it.
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its an old oil company marketing gimmick to get people to buy more oil, i think the same guy convinced many people that Super Deluxe hightest supreme gold top tier gasoline was better for your car than just plain old regular never mind that your car was probably designed to run on regular.
