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Some people use Synthetic 5w30 some use plain 5w30. What is the best practice and experience say for you folks?
 

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parry said:
Some people use Synthetic 5w30 some use plain 5w30. What is the best practice and experience say for you folks?
Parry-

Syn vs. dino oil? There is no right or wrong choice. Each type of oil has it's benefits.

Check out the threads in the Maintenance section. The are dozens of threads and hundreds of posts that discuss this very same question.

Some people swear by synthetics, others would never consider using anything other than dino oil.

Whatever you choose, just remember to change the oil on a regular basis. A delinquent oil change schedule will have more of an impact on engine performance and longevity than your choice of oil.

-njjoe
 

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Parry,

njjoe is right. It is far more important to change oil at regular intervals than which one to use: sync v. dino. I went with sync as I believe Mobil1 is superior to any dino oil. But ultimatly it is up to you to decide.

JUST CHANGE OIL ON REGULAR BASIS!!!!!!
 

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Ditto what people said above.

I use synthetic because it provides superior cold start protection and cleaning properties. The cost is minimal for me since I change it myself. If you have the shop use their synthetic oil, you might find that $25 oil change ballooning up to $50 or $60.
 

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Ditto what Eric said--I use Mobil for the same reasons.

Also, syn's don't thicken with cold like dino's do. They flow cold the same as they do hot.

Something I haven't seen anyone talk about is the bypass pressure relief valve found on all engines. When dino oil is very cold, there is a piston shaped valve with a spring behind it in line with the oil filter, which opens if too much pressure is encountered there. It diverts the oil from the filter to the mains etc so there won't be starvation and so it won't over pressure the filter.

In old VW engine hopups (and racing engines) we used to put in a much heavier spring to keep this from happening.

Modern engines started using lower and lower viscosity indexes because of this. The first number in 5W30 indicates the flow rate at a certain temp--the lower the better. The second number indicates the film strength at a certain temp--the higher the better. It is the film strength that keeps your mains from grinding. The flow rate is of course for everything else that needs oil ASAP.

There used to be a few kits around that allowed you to pressurize your oil circuit before cranking--as this is where most of your wear is encountered because of starvation. I have often wondered why OEM's don't include this stock.

But, the bottom line for me to use syn's are:
The flow rate when cold.
Syn's don't drain down as dry when the engine is sitting.
And the film strength when hot--that is where dino falls behind syns.
;)
 

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mgthe3 said:
...I have often wondered why OEM's don't include this stock....
What? And make the engine last longer and make less profit by selling less parts and labor????
 

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Nothing against anyone who uses synth oil but I dont' think its necessary if you change your oil properly/frequently.

For over 13 years I used standard Mobil Oil, (10W-30 summer, 5W-30 in the winter) in a 1989 Nissan Pulsar... it was a 4 cyclinder that I ran hard.... Manual tranmission, high RPMS and freq fast revs as I was double clutching.

In that time, and with 210,000 miles... that car never lost oil between changes... the engine was bone dry and holding on the dip stick. I had cold starts in the NH winters as well. I used Nissan Oil filters 100% during that time. I also only filled crack case to 3/4 full.
 

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Gonzo said:
I also only filled crack case to 3/4 full.
Gonzo-

You got my curiosity going with that one. Why only fill the oil to the 3/4 mark?

-njjoe
 

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njjoe,

because you really do not want to overfill as it has the potential do damage the engine…
 

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njjoe said:


Gonzo-

You got my curiosity going with that one. Why only fill the oil to the 3/4 mark?

-njjoe
I think he meant 3/4 up the full mark on the dipstick - the full mark range being generally 1 qt.
 

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If you don't have a windage tray (scavenges excess oil from the crank) or a dry sump system (oil pump that is not in the pan), over filling your crankcase causes the journals/big ends of the rods to smack the oil in the pan. Not only will this cause more work for the crank to do, but it tends to put bubbles in the oil which makes it hard to pump and leaves holes in the oil film on your bearings. It also can cause the crank to throw it up in the air instead of being down in the pan for the pump's supply.

And yes, my paw-inlaw has a 71 ford pickup with over 400k miles on it with the only engine repair being a valve job on one head. He has used quaker state straight 30 weight the entire time.
He changes his oil religiously at 3k miles or 4 months, whichever comes first.
He warms his engine completely before he moves an inch.
It is a 3 on the tree (steering column) manual transmission and I think the engine has probably never seen 4k rpm and rarely sees three.
Original clutch--this shows how easy he is on her.
One brake job.

To me it is an enigma to ford and quakerstate.
:2:
 

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Eric L. & Kris-

Thanx. I had interpreted it to mean the crankcase was filled with only 3 quarts instead of 4. Now after reading your replies and rereading Gonzo's statement it makes sense.

I understand the problems with overfilling the crankcase.

Here's a good one. I remember as a kid I went to my Grandfather's garage (he owned a small trucking company) to change the oil in my Uncle's car. This was my 20-something Uncle's very first car, so he was "mechanically-inexperienced". My Grandfather showed my Uncle how to drain the oil and change the filter. Once that was done he told my Uncle to fill the oil through the valve cover cap and then went into the office. Well, my Uncle John took the oil hose and, following my Grandfather's instructions, proceeded to fill the engine with oil. When my Grandfather came back the oil was filled to the top of the valve cover! True story.

-njjoe
 

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Good story.

:D :D :D :D

njjoe said:
Eric L. & Kris-

Thanx. I had interpreted it to mean the crankcase was filled with only 3 quarts instead of 4. Now after reading your replies and rereading Gonzo's statement it makes sense.

I understand the problems with overfilling the crankcase.

Here's a good one. I remember as a kid I went to my Grandfather's garage (he owned a small trucking company) to change the oil in my Uncle's car. This was my 20-something Uncle's very first car, so he was "mechanically-inexperienced". My Grandfather showed my Uncle how to drain the oil and change the filter. Once that was done he told my Uncle to fill the oil through the valve cover cap and then went into the office. Well, my Uncle John took the oil hose and, following my Grandfather's instructions, proceeded to fill the engine with oil. When my Grandfather came back the oil was filled to the top of the valve cover! True story.

-njjoe
 

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For what is worht that '89 Pulsar also had the original clutch AND only one set of front pads! (First set replaced at 100K and it was just about due for a second.)

Sorry for the confusion.... I should have 3/4 full betweed "ADD" and Full" and the dip.

On the Murano, that is adding 4.0 qts after I drain it on a flat surface. That includes me adding some of that 4 qts to the oil filter when I replace it.
 

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Oil change and type

I've been using Wal-Mart's "finest synthetic" since about 10K and change the filter at 5K and oil at 15K. Will change to Royal Purple at the 60K service time. Car does what is is supposed to. :eek:
 
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