10w-40 instead of 5w-30 okay mechanic says?

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My girlfriend owns a 1997 Saturn SL2 that requires 5w-30. Her mechanic always puts in 10w-40 bulk oil every 3k she gets an oil change. The mechanic says there is nothing wrong with 10w-40 instead of 5w-30. Is this true?
 
LOL! If your GF's saturn calls fro 5W30, why not put 5W30 into the car?

Don't tell some of the mechs here but this may be the typical symptoms of lazy mech, or bulk purchasing of the wrong grade. Similar to one of the mech I've known for years: anything he services, he throw in 10W30. Never stock up on 5W30, 5W20, 10W40. If the bearing rattles, throw in a can of motor hunny and charge the customer. If the engine smokes, blame it on the aging engine, throw in another can of motor hunny (or AssTeePee) and then charge the customer. If the customer asks for 5W30/5W20, he would insists nothing wrong with 10W30. Why? He pay less for bulk 10W30 delivered to his doorstep.

There could be some other reasons behind this but frankly, with 5W30 of same price as 10W30, and 10W40 is a bit on the "thicker" side of most passenger vehicle's diet, some mechs or shops just simply wouldn't care about it.

This happened to my friend's 1994 Accord. His mech did an oil change with 10W40, reasoning that aged Honda engine with loose bearings shall go with "thicker" grade of oil. Truth is, this engine is still within factory spec (no bearing or rod knock). and as soon as we change it out and put back some Q-state green 5W30 dino, it instantly restores the peppiness of the engine.

My observations. YMMV.
 
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The mechanic says there is nothing wrong with 10w-40 instead of 5w-30. Is this true?




That's a loaded question; I think I'll kick back and enjoy this thread.
popcorn.gif
 
Maybe 40w oil is thick enough to stop a few of his customers vehicles from smoking and burning oil as they age under his care.

I don't like the idea of bulk oil. We've done VOA's and you sometimes get a lot of things for free, like paint chips, moisture, rust, grit, insect parts, other kinds of things that the barrel had on the fill before it got the current oil. We've taken samples from the very bottom of the barrel and found about 6 ounces of water, really grungy water and soap along with cleaning solvents that stayed with the oil and did not migrate up into the oil. I think that what you get out of a quart bottle or a gallon jug is a better bet than something someone has to clean out before it gets refilled. I will never use bulk oil. It's a bad bet made buy you to help the shop or dealership make a few extra bucks.
 
15W-40 HDEO is a common fix for Saturns oil use problem. Many people also up the viscosity in older vehicles as the clearances open up.

If the engine is in good condition and doesnt have an oil use problem she's just waisting gas by using 10W-40 but I seriously doubt it will harm the engine.
 
I have come to view my Saturn a little different. I have a 99 SL2 that uses about 1 quart per 1,000 miles. My car does not require a specific weight of oil. It requires to be topped off with any SM oil I have on hand. I have used 0w-40, 5w-30, and 10w-30. Look up some of ToyotanNSaturn's UOA's with the variety of oils he has put in his SL2. Currently, I think he is using 5w-20, something GM does not recommend. He has also used a Xw-50 weight oil. So, to me the main thing is keeping the oil topped off. The weight of the oil is secondary.
 
Yep... My Cousins uses 1 Qt every 1200 mi and gets SuperTech 10W-30 out of a 5 Qt Jug. He changes the Filter Every 12 Months (Pure One) and drains it every 3 years. After all its a self changing automobile (5 Qt Every 6000 mi).

EDITED: To correct my Math!
 
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Saturns can have oil burning problems and the mechanic may be aware of this issue. 10W-40 is a simple fix to obtain better ring seal to control the consumption.

10W-40 can produce some gas mileage penalties during short trip situations in the colder winter months in Maryland, but the offset may be better ring seal for more power & fuel economy gains.
 
He must have gotten a very good deal on the 10w40 bulk oil and this mechanic knows that any weight oil will keep an engine running for many years.
 
My buddy works at a used car dealership where they fill every used vehicle with 10w40 when it comes in. This is done to keep the engine noises to a minimum. The customers just think they are buying a vehicle that is running great.
 
hopefully the 10w-40 helps the oil burning issue a bit. The car is also on its second auto-rx clean phase with that oil.
 
Quote:


Yep... My Cousins uses 1 Qt every 1200 mi and gets SuperTech 10W-30 out of a 5 Qt Jug. He changes the Filter Every 12 Months (Pure One) and drains it every 3 years. After all its a self changing automobile (5 Qt Every 6000 mi).

EDITED: To correct my Math!




Sorry to say...I did something like this at one time...too bad the sludge doesn't get consumed with the oil.
 
Go out & buy the 5-30 and change it for her. She'll love you for it. Next thing you know you'll be trading it in on a minivan.
 
Quote:


My girlfriend owns a 1997 Saturn SL2 that requires 5w-30. Her mechanic always puts in 10w-40 bulk oil every 3k she gets an oil change. The mechanic says there is nothing wrong with 10w-40 instead of 5w-30. Is this true?



5W30 or even 0W30. If its buring any oil try some Castrol Syntec 0W30 its a tad thicker than normal 30W oils.
 
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