New Member with a question

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Jan 23, 2003
ON, Canada
I came across this board a few days ago, and I was amazed by the knowledge of the people on here. I am an avid auto enthusiast, primarly interested in American V8 powered vehicles. I do all my own maintenance and modifications to my cars. Anyway, I am new to oil tech so I thought I would join this group to learn more.

Right now I have a Olds 307 with higher miles that I am running Pennzoil 10W30 mineral oil. I am wondering if switching to a 15W40 oil would be a good idea to help this engine reduce oil consumption. The car still has very good oil pressure and has no engine problems. The engine also tends to dirty its oil up pretty quickly, so I though that the stronger detergents in a 15W40 oil might help out. The engine oil was very dirty when I first acquired the car 4 years ago. Over time, my religious oil changes have helped improve the oil, but I am hoping it will get better. The car was not maintained as well and saw a lot of idle time by the previous owner.

Also, will the thicker oil harm the engine? These old Olds V8's have larger clearances than modern engines, so shouldn't the 15W40 be okay? I don't want to increase engine wear with the thicker oil either.

I am just looking for a good over the counter oil that will help this engine last long, and use less oil. This engine is not used in the winter, so it will likely not see temps below freezing. I am new to oil tech, but I am trying to learn. Thanks in advance.

[ January 24, 2003, 11:36 PM: Message edited by: Oldswagon ]
If you're not using this car during the winter up there, then the 15w40 shouldn't be a problem. However, if the engine is actually burning some oil, then the higher ash level in a HD oil may cause you to have some combustion chamber/spark plug deposit problems.
fellow Ontarian!

How much consumption do you have on the Olds? Have you considered doing oil analysis? You'll find that a lot of us on here seem like oil analysis junkies, but it is true, it's probably the best way to determine which viscosity of oil will provide you with the lowest engine wear.

I would bet your car would show lower wear with the 15w40 than with 10w30.
Thanks for the great help so far guys. The car currently uses about 1 quart/1000 miles. The car does leak oil though. Some of the oil leaks are on my to do list that I haven't got around to doing. As far as oil burning is concerned, it doesn't show any signs of any significant oil burning. It has no blue smoke at start-up, under loads, or any time for that matter. The last time I changed the plugs it showed no signs of burning oil either.

I hadn't really ever thought about running an oil analysis before I came to this site. How much do they cost? And is there any place in Ontario (I am in Northern Ontario) that does this?

Right now, I would just like to get at most three more trouble free years out this engine. I am currently looking for larger small block Olds to rebuild and replace my 307 with. Until I can find one, I need this 307 to be reliable transport at minimum cost.

I saw a virgin oil analysis of Pennzoil 15W40 in the archives. Would this be a good choice to run or should I use another brand? I read about the benefits of moly and I would like to run a oil with some moly in it. But since I want to keep things simple on this engine, I just want an over the counter oil that I can get from the local Wal-mart or Canadian Tire.

Thanks again for any info.
'ya actually got a chevy engine there-I believe its a strocked 283. Its a wondergul engine. They do use oil and the oil gets dirty quick. I assume you have a main seal leak. Most people used 40 wt's in them. I had a '69 Camaro with this engine. I got rid of it at about 100K-no problems with it. Kid who bought it rapped it around a tree a week after I sold it to him
. It used about a quart every 1500 miles from new and stayed that way. I will tell you that once they start using oil they go f-a-s-t
. Great engine. Very under-rated. Might have been one of Chevy's best.

[ January 25, 2003, 05:57 PM: Message edited by: Al ]
No Al, this is an Olds engine for sure. It was made in the 1980's not the late 60's or 70's. I do know of the Chevrolet 307 as well, but this is a totally different engine. These Olds 307 engines are common place in 80's fullsize and midsize GM cars.
If your going to use a 15W40, the Pennzoil Long Life 15W40 would be a good one, and it has moly in it. I have a lot of mixed fleets here in Wisconsin using it.
Yes, there is an oil analysis lab in Ontario, it's right here in Mississauga actually, not too far from me. I'll send you the contact info in a private message.
Thanks for the info on the analysis labs Patman. I am not too far from Mississauga, so that location would be ideal for me. I checked out that web page link that you sent, but I couldn't seem to find anything on cost. Do you know what it would cost for an analyisis?

Johnny, that 15W40 long life was the oil I was thinking of. It was the one that had the virgin analysis sample in the archives. I guess I will try it out and see how it works. The car is in storage right now, so I will have to wait until spring when I take it out.

Thanks again for the help. And if anyone has any more input, feel free to comment. The more the better.
My mistake. I believe they cancelled the engine in '77 or '78. Also during this period of time or a little later there were a number of law suits bc some GM vehicles had engines made by the Chevrolet in them. I know that Olds was one the affected vehicles.
I have no doubt that you are correct in what you say. 307 cu. in. is very close to 5L. Hard to believe they changed it-seems like it would have been hard to beat as is
Thanks for the info

Enjoy the board

[ January 26, 2003, 03:48 PM: Message edited by: Al ]

Originally posted by Oldswagon:
Thanks for the info on the analysis labs Patman. I am not too far from Mississauga, so that location would be ideal for me. I checked out that web page link that you sent, but I couldn't seem to find anything on cost. Do you know what it would cost for an analyisis?

I just sent you another private message with the info.
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