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    by: Tom Torbjornsen | AOL Autos
     

    Dear Tom,

    I just bought a 2009 KIA Optima. The owner’s manual says I should use 5W20 oil in the engine. My dad used to fix cars and he said that this oil is too thin and that I should use “Straight 30 weight” in the winter and the 5W20 in the summer. Is he right?

    Sandy from Salt Lake City, UT

    Sandy

    Gently tell your dad to stifle himself. Use the 5W20 oil in your KIA. The carmaker selected this oil because the engine operates under tight operating tolerances. If you put heavier oil in it then you’ll damage the engine, not to mention void your warranty should the need arise to make a claim. Years ago dad’s advice might have been acceptable, but now it’s way outdated.

    Tom

    Several years ago a woman called my radio show with the same question. However, she had already followed her husband’s advice and the engine in her new Ford seized due to lack of lubrication. She had to buy a new engine on a car that had only 25,000 miles. Too bad. Here are some things you should know.

    What Type Of Oil Do I Use?

    The answer to this question is in your owner’s manual under the maintenance schedule. The carmaker outlines what weight (viscosity) to use. If it says 5W20, use it. Carmakers make engine oil recommendations based on extensive lab testing, road testing, and research done in conjunction with petroleum companies. You can rely on the recommendation because it’s based on a lot of research.

    Should I Change The Weight Of The Oil Based On Time Of Year/Temperature?

    No. Multi-viscosity oils are designed to adjust their rate of flow (weight) based on outside and inside engine operating temperatures. When you read an oilcan that has a viscosity rating of 5W20 it means that the winter flow rate of the oil is 5 (thinner) than the summer flow rate (thicker). Multi-viscosity oils thicken up in the summer when the temps are hot and oil tends to thin out. When it gets cold they thin out in order to maintain optimum flow rate in all temperatures.

    What About Synthetic Oil? Can I Use It?

    In most cases you can switch over to synthetic oil. However, consult your owner’s manual before switching to make sure there are no caveats. I like synthetic oil because it is chemically fortified to withstand the rigors of the internal combustion engine environment. While it is not impervious to, it is highly resistant to viscosity breakdown from heat, friction, and chemical contamination. Synthetic oil flows better in winter and provides superior lubrication and protection in the summer when most oils break down under intense heat. If you switch over, just make sure you use the viscosity recommended by your carmaker.

    How Often Should I Change The Oil?

    When using good quality synthetic oil, change it every 5 - 7 thousand miles or six months, whichever comes first; and make sure to change the filter. When using petroleum-based oil, change it every 3 - 5 thousand miles or three months. As with synthetic, change the oil filter with a high quality filter every time you change the oil. Why the longer drain intervals with synthetic oil? It’s tougher, therefore you can go longer between drain intervals. Based on my research of synthetic engine oil, AMSOIL is number one and Mobil One is number two.

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    1 - 20 of 253 Comments
    tombeaversr Oct 05, 2010 9:47 AM
    The oil change inter for my Buick should read 25,000 miles not 2500. I,m a lousey typist. That's 313216 miles with AMSOIL 10W-30 and AMSOIL oil filters.
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    tombeaversr Oct 05, 2010 9:42 AM
    to intreg. put in a bottle of AMSOIL engine flush. Let idle for 25-30 minutes at high idle speed. Drain old oil and replace with new oil. I reccomend AMSOIL 10W-30, but I am prejudice and also a AMSoil dealer with over 313,000 miles on my Buick.
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    tombeaversr Oct 05, 2010 9:36 AM
    I have a 1999 Buick Lesable with 313,216 miles on it and have only change the water pump(vanes worn to a nub). I use AMSOIL 10W-30, AMSOIL oil filters and I change the oil every 25,00 miles. I also drove 1990 Ford Festiva 282,000 miles using same combinations. That should settle the argument of extende drain intervals for synthetic AMSOIL.
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    nwkane1 Oct 02, 2010 8:48 PM
    You are absolutely right on the oil viscosity. I am old school and love to do my own oil changes. the last car I bought in 2008 stated that I need to used 5w20. after 6 months of owning the car I switched my oil to 20/50 as I had very good engine life in my previous car (270,000 miles). 2 months after I switched from 5/20 to 20/50 oil, my engine blew up. I took it to the dealers where I brought the car and they told me the oil I was using was wrong. To make a long story short. The dealer covered my engine under warranty and spanked my error. It pays to stick with the required specifications as stated.
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    biewer12345 Sep 01, 2010 4:32 AM
    Well it seems the other post is misleads with the topic, the topic is very interesting specially who are fashionate with cars and beginners like me. But I really learn from you Tom, thank you.
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    dabbssd May 05, 2010 10:53 AM
    bowtiesaly, "Yes the manufactures do tell you in most of the cars now a days to use 5w/20 in reality your motor wont last long using this grade,........" Your statement is incorrect. Vehicle/Engine longevity has nothing to do with oil weight/grade. New Engines today have much closer tolerances than ever before. Therefore, a 10W-30 may not lubricant efficiently, while a 5W-20 will, due to being able to flow where the 10W-30 will not. Case in point; AMSOIL 0W-30 Motor Oil lubricats/protects better than Pennzoil Platinum 5W-30, Motorcraft Synthetic Blend 5W-30, Quaker State Full Synthetic 5W-30, Havoline 5W-30, Mobil 1 Extended Performance 5W-30, etc. as proven by independant tests. I personally run AMSOIL 0W-30 Signature Series & AMSOIL Filter, changing both only once a year or 25,000 miles, which-ever occures first. (In my case it's once a year). My Vehicle: 2003 Pontiac Vibe, Current Miledge: 70,142, Current Fuel economy: 29.3CTY./34.30HWY. Questions/Comments? See my website: www.lubedealer.com/worldsfinestsynthetics or contact me. (Contact info on website homepage).
    Report This
    li6mcch1 Mar 07, 2010 6:57 PM
    dearsir i have a 1994 mercury grand marquis it has engine light on when in its first 20 min after warm up i replaced egr and other things but still comes on gets horrible gas miledge can u help it has a 4.6 v8
    Report This
    wrench701 Feb 25, 2010 8:39 PM
    henryptnm---- Jan 11, 2010 10:11 AM I own a 2004 Ford Ranger and it has 107 k miles and I been using Vavoline Max-Life 5w-30 and I have no problems with it. I bought the truck used and it had 91 k miles. It was all turnpike driven and the previous owner maintained it. I tried Motorcraft 5w-30 synthetic-blend and it started losing its viscosity and then switch to Vavoline, no problem. I'd like to contact the lab that made the "viscosity breakdown test" for the results. Could you please post the address and phone number? Thank you.
    Report This
    dabbssd Feb 22, 2010 2:45 PM
    David A. Bess Lifetime/T-1 Certified/Contracting AMSOIL Dealer FOR ALL YOUR VEHICLE MAINTENENCE/CARE NEEDS, CONTACT ME; http://www.lubedealer.com/worldsfinestsynthetics Email: amsoilcertified@yahoo.com or dabbssd@aol.com AMSOIL First in Synthetics since 1972
    Report This
    brombergcl Feb 12, 2010 2:08 PM
    AMSOIL T-1 Certified Direct Jobber - Charles Bromberg www.lubedealer.com/wholesale AMSOIL- Catalog Request AMSOIL- Dealer Information Request 877-862-9922 or 256-237-6090 AMSOIL- Ea-Air Filtration Video on YouTube
    Report This
    brombergcl Feb 10, 2010 6:33 PM
    AMSOIL T-1 Certified Direct Jobber - Charles Bromberg www.lubedealer.com/wholesale AMSOIL- Catalog Request AMSOIL- Dealer Information Request 877-862-9922 or 256-237-6090
    Report This
    henryptnm Jan 11, 2010 10:11 AM
    I own a 2004 Ford Ranger and it has 107 k miles and I been using Vavoline Max-Life 5w-30 and I have no problems with it. I bought the truck used and it had 91 k miles. It was all turnpike driven and the previous owner maintained it. I tried Motorcraft 5w-30 synthetic-blend and it started losing its viscosity and then switch to Vavoline, no problem.
    Report This
    macthemgbdr Jan 10, 2010 10:27 PM
    I have seen dissolved oil filters, but only in seriously neglected vehicles. I do recall reading in a lube shop trade pub several years ago (06?) that (this writer's tests) showed that OEM branded filters did hold up better over the extended drain intervals specified in the owners manual than did some of the "cheepo" unbranded filters some lube shops used. The shop I worked for at the time was offered some for less than a dollar; we used AC Delco, and that came to our rescue one time when a customer tried to complain that we used poor quality products and that this was the reason his engine....(he'd blown a head gasket or done something and had the oil changed again at a competitor that used a cheap filter). We could show that we'd used a PF-whatever it was, and he and his lawyer went away.
    Report This
    corkswatch Jan 10, 2010 11:56 AM
    Void your warranty by using 10W/30 huh? With the exception of high end performance cars like an M3, someone show me an owners manual that says under no ************* should you use 10W/30 in the engine lol.He's confusing RECOMMENDED with REQUIRED. Most manufacturers RECOMMEND thinner oils for improved mileage, but clearly state you can use other weights depending on the climate/driving habits. Unless you live in Alaska, Canada or North Dakota, you can use 10W/30 year round in 90%+ of the cars out there. I've tried thinner oils in my turbo Subaru and they just burn off. This guy is giving opinion as if it's fact and he's just wrong.
    Report This
    dabbssd Jan 09, 2010 9:55 PM
    TO: intregg, I will be glad to help you. I know exactly what to do to clear this problem up. Please contact me ASAP. email: dabbssd@aol.com
    Report This
    dabbssd Jan 09, 2010 8:35 PM
    TO: charlesqueenc: AMSOIL IS SUPERIOR TO Royal Purple (and all the other copycat brands), tests prove it! For more info contact me on one of my emails: amsoilcertified@yahoo.com or: dabbssd@aol.com or on my Website: http://www.lubedealer.com/worldsfinestsynthetics
    Report This
    dabbssd Jan 09, 2010 7:31 PM
    TO: firstimpressions, A>You may be a service manager, but your still no expert. I have been a AMSOIL Dealer since 1985, have run NOTHING BUT AMSOIL in everything I own & went 17 MONTHS before last changing my Oil & Filter in my '03 SUV. B> AMSOIL warrants its Gasoilne Motor Oils & AMSOIL Oil Filters for 25,000 Miles or 1 full calendar year, which ever occures first, (Except our XL Oils, they are 7,500 Mile Oils) & all AMSOIL Diesel Oils for 15,000 Miles or 1 year. C> AMSOIL & Donaldson (Also sold by AMSOIL) Full Flow Oil Filters filter down to 3 Micron particle size. AMSOIL By-Pass Filters filter down to LESS than 1 Micron! You ask for a better filter? You've just found the BEST OIL &FILTERS IN THE WORLD!! dabbssd@aol.com Or amsoilcertified@yahoo.com http://www.lubedealer.com/worldsfinestsynthetics
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    tyrebitre Jan 09, 2010 7:22 PM
    "Multi-viscosity oils thicken up in the summer when the temps are hot and oil tends to thin out. When it gets cold they thin out in order to maintain optimum flow rate in all temperatures." No, that is not the way oils work: Using a 5W20 as an example, it doesn't "thicken up" as it gets "hotter&**************** thins with heat - what it does is THIN LESS than a straight weight 5W would do. Long chain polymers are added to a thin base oil (5W) which uncurl as the oil heats and prevents the oil from THINNING any more than a straight 20W oil would at high temps - it doesn't "thicken the oil". A HOT 20W oil is always thinner than a COLD 5W. If you don't think so, a simple experiment will prove it: take a quart of 5w and see how long it takes to empty when turned upside down: now, heat some 20w to whatever your car's normal operating temp is - turn it up and see how long it take the same amount to flow out.
    Report This
    cecejoe94 Jan 09, 2010 7:22 PM
    wesson
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    wukkamon Jan 09, 2010 7:18 PM
    @ firstimpressions... With todays advanced oils (and yes, a decent filter) there is no need to change every 2500 - 3K with synthetic. Going by the manual, my 03 Honda Accord should have the oil changed every 10K. Now with Honda having one of the highest reliability rates amongst carmakers, do you think they'd recommend that at the risk of their reputation? Yeah, I'm still old school so I won't go past 7K but 2500??? Well, I guess being "a service mgr at an oil change shop", you do need to keep the business flowing.
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