motor oil weight/preference


Old 01-06-07, 07:37 PM
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motor oil weight/preference

i have a 2005 toyota 4wd v6. calls for 5w30 motor oil. at 5000 miles i switched it to synthetic mobile one that's good for 15000 miles. at 20k i put 10w30 synthetic in at recommendation of fellow worker. another fellow worker stated he only runs what is recommended by man. any pros/cons for weight or for the synthetic? i did notice a little better mpg when i initially switched to the synthetic 5w30. if i switch back to 5w30, any specific way to do this?
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Old 01-06-07, 08:18 PM
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Before we can recommend an oil, we need to know your climate, driving habits (freeway?.. city?.. short trips?), and how many miles you put on each year.
Old 01-06-07, 09:57 PM
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have a 2005 toyota 4wd v6. calls for 5w30 motor oil. at 5000 miles


if thats what they call for then thats what I would use

why would you think that you , your co workers or anyone here would know more than the engineers that designed it ?

change it with a OEM filter every 5k or less and don't mess with the synthetic's
Old 01-07-07, 07:36 AM
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if the OEM says 5w 30, use it.
Old 01-07-07, 08:40 AM
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I'd stick with the manufacturer's reccomendation. I usually up the thickness one grade when a car goes over 100K miles, but not before that.
Old 01-07-07, 08:57 AM
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Ive used 10w 30 for years even though the manufacture called for 5w30. You'll be fine. If you would like to use synthetic, just use it in 5w30 weight , if it will make you feel more comfortable.
Old 01-07-07, 09:34 AM
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Engine clearances and oil weight are both used when manufacturer recommends oil viscosity. Not paying attention to this and using heavier than recommended is asking for premature wear as heavier oil cannot flow into tight clearances as easily. The owners' manual is what to follow no matter what the "experts" here or elsewhere say based upon their sample of 1 expertise stories. Changing the oil at recommended intervals allows for removal of acids, water, and metal wear particles; additionally, the additive packages added to oils wear out in time and cause need for new oil even though lubricating qualities may not be degraded.
Old 01-07-07, 11:38 AM
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Oil Recommendations

Bob22 took the words right out of my mouth!
I too am a big believer in the superiority of Mobil 1 lubricants. They are all I use in my vehicles, mowers, generators, oil can etc. I also use Mobil 1 chassis grease. Testing at General Motors confirms that Mobil 1 is a great choise in engine oil.

Last edited by stickshift; 01-07-07 at 02:06 PM. Reason: Removed quoting of entire post
Old 01-07-07, 12:52 PM
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Remember that Toyota has had some problems with engines sludging. You should still be under warranty, but if you cannot prove that you followed their recommended oil weights, and especially oil change intervals, you may void the warranty.
Old 01-07-07, 03:31 PM
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i live in central pa. average about 20000 miles a year on miles are mainly b/f to work now, 17 miles one way. i currently run the "fully synthetic extended life 15000 mile mobile 1" in my truck. i put the 10w30 in about 1000 miles ago. by the looks of these responses i will be draining the 10w30 real soon and going back to the 5w30. my question now is, i will be changing the filter when i do this, are there any other measures i need to do or will it be ok to just replace the filter and put the 5w30 back in? does it have any effect if you mix the two? also, should i just stay away from the synthetic and put the mobile one 5w30 in and change at 5000 mile intervals, per the owners manual? i rack up the miles pretty quick i just thought the synthetic extended oil would save some time in between changes. maybe that wasn't a good idea.
Old 01-07-07, 04:01 PM
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engine oil

I agree with the others about aynthetic oil being far superior than mineral oil, I only use synthetic on my wife's suburban 6.0L 4x4, however, 15k miles before oil change seems a little too much, yous should 6k or 7k miles at the most and only if you also use a high performance oil filter such as Mobil 1 or K&N.
Remember the point of using synthetic is to have an extra layer of protection on your engine not really to squeeze so many extra miles out of every oil change.
Old 01-07-07, 04:33 PM
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motor oil weight/preference

I guess the synthetic works, but no real proof. I am in a reasonably tough climate - hot summers and cold winters.

Some of the results we heare about may be due to improvements in recent engine production accuracy.

I used it in my Corvette because it came with it and was required. Never pushed and always got great mileage.

I have used it in my Jimmy with 120,000 miles on it and have never seen the oil level drop, so I never added between changes (10,000 miles). Same for my wife's Blazer with 85,000 miles. Not really much of a real test today.

The Formula 1 cars use only synthetic oil. Currently they are rev limited to amout 18,500 rpms, but this will probably go up. Some are looking at 0 (zero) weight synthetic!!

The days of the old oils and cars are gone.

Old 01-08-07, 09:37 AM
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5w 30 the first# stands for the thickness in cold weather it moves faster on start up so go with the 5w 30 it will give you beter protection on start up
Old 01-08-07, 11:14 AM
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FWIW, we have one of these long oil threads going about once a year. If anyone wants more of the pro's/con's you can search the archives. Think we had about 50 posts to thread last time.
Old 01-08-07, 03:41 PM
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I work as a lube tech in a paper mill. We just had a seminar with a rep from Noria. We asked questions about syn oil in vechiles. He recommended synthetic because our climate can be -25 in the winter to 90 in the summer. Cold starts with mineral oil will take life off your engine. As for your filter look at the beta ratio, the lower the better.

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