350 Oil Question
Thread Starter
Racer
Joined: Apr 2008
Posts: 436
Likes: 2
350 Oil Question
For now I have a 350 and need to change the oil. Right now the engine burns about a quart every 300 mi or so. The previous owner has 5w-30 Mobil1 syn in it (still in there). I was reading about dino vs synthetic and thought maybe the type of oil used may have something to do w/ it. Do you guys recommend using a different type/weight of oil? Also, I'm assuming 5-6 quarts, correct? And lastly, can I pick the filter up at Autozone or do I need to get it somewhere else (i.e. are Autozone's crap and/or do they have the correct filter in stock on their computer system)?
Melting Slicks
Joined: Mar 2008
Posts: 2,989
Likes: 198
From: Meriden CT
I would use the cheapest oil I could find in that motor. 300 miles to the quart is bad enough for me to not care too much about the motor. I'd use any oil in it until the replacement. My 2 cents.
Le Mans Master
Joined: May 2002
Posts: 5,086
Likes: 786
From: Lebanon Township New Jersey
Autozone will have a filter adequate for that engine. If I were you I would only change the filter and I would start using 10w 40 weight conventional oil. You can mix it into the synthetic. Your getting plenty of oil changes at 300 mile per quart. BTW - total volume for an oil and filter change is 5 quarts.
Melting Slicks
Joined: Aug 2005
Posts: 2,683
Likes: 34
From: Working on the car NY
imo, at 300 miles /qt., your oil is being constantly changed anyway. I'd just change the filter at 3000 miles and stop using syn. and go to a heavier wt. dino oil. Brand IMO really doesn't matter for that particular engine of yours.
Instructor
Joined: Dec 2007
Posts: 247
Likes: 0
From: Sanderson Texas
uh the synthetic oil will foul plugs less
I had dino oil in mine 1qrt 300miles + 2 plugs fouled
I put synthetic in it
now 1/4 quart every 300 miles 700-800miles before 1 plug fouls
(getting less too)
I wouldnt quit changing it just go 6-8k instead of 4k
I had dino oil in mine 1qrt 300miles + 2 plugs fouled
I put synthetic in it
now 1/4 quart every 300 miles 700-800miles before 1 plug fouls
(getting less too)
I wouldnt quit changing it just go 6-8k instead of 4k
Thread Starter
Racer
Joined: Apr 2008
Posts: 436
Likes: 2
Ok, so I'll try 10w40. Do you guys recommend the "high mileage" stuff? I think it has some additive to stop leaking seals (which I'm guessing is another part of the problem), but not sure if it's really all that it's cracked up to be.
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Burning Brakes
Joined: Mar 2008
Posts: 1,038
Likes: 39
From: Denver, CO
St. Jude Donor '08-'09-'10
im gonna say it even though its prolly not the most asked for advice.. time to find the leak.. maybe even time for a complete rebuild.. id recomend the complete rebuild anyway, at least if this is not your only means of transportation.. if it is, i hope you have lots of money for oil
Race Director
Joined: Sep 2001
Posts: 10,560
Likes: 439
From: Wellington, FL
St. Jude Donor '11 thru '25
I personally wouldn't think about a rebuild until you find the problem as to why you go only 300 miles on a quart. It could be leaking a lot, it could be valve seals, a clogged PVC valve, or some other problem that could be an easier fix than tearing the engine apart. 
Thread Starter
Racer
Joined: Apr 2008
Posts: 436
Likes: 2
I'm putting in a new engine anyways, so I'm not doing any work to this engine, though I think it's the seals. But really I don't care too much since it's only a matter of selling the other car before I get the new engine. I'll just deal w/ burning oil until then...the engine runs strong otherwise.
Le Mans Master
Joined: Sep 2001
Posts: 7,739
Likes: 630
From: Unreconstructed, South Carolina
Shell Rotella T 15W-40 ... it's not synthetic, it's about $10/gallon at walmart ... it'll work good for your new motor too ... unless you live in a very very cold climate ... fill in your profile with approximate geographic location.
Racer
Joined: May 2008
Posts: 353
Likes: 0
From: boulogne buenos aires
I'm also hanving some doubts about my oil consumption/burning. Engine was rebuilt a couple of years ago but since then only 5k miles were driven.
I had the car stored for a couple of years undergoing a frame off. In that period the engine remained with oil and not a single change in the level. I started using it again on july 2007. Chance the oil in november 2007 (fully syn) and since then I,ve noticed the oil level goes down. i still dont now the rate but i will keep an eye. My question is If it could be the syn oil ,as the car runs clean (I guess if it burns oil I should notice it through the exhaust smell/white blue smoke) and there are no oils leaks. should I concern?
I had the car stored for a couple of years undergoing a frame off. In that period the engine remained with oil and not a single change in the level. I started using it again on july 2007. Chance the oil in november 2007 (fully syn) and since then I,ve noticed the oil level goes down. i still dont now the rate but i will keep an eye. My question is If it could be the syn oil ,as the car runs clean (I guess if it burns oil I should notice it through the exhaust smell/white blue smoke) and there are no oils leaks. should I concern?