Team Chevelle banner
Cancel
Create thread New Garage Forums

Best Engine Oil Choice?

Jump to Latest
1 - 18 of 18 Posts
M

mikehartwell

· Registered
Joined
·
50 Posts
Discussion starter · #1 ·
There are a bazillion threads about engine oil, but I have come to rely on the info from this board.

My new 434 sbc is running awsome and I want to keep it that way. I think the generally accepted oil weight for this type of engine is 20-50W. I have a 7 quart Moroso pan. During the engine rebuild, the crank throws were shaved (they are slightly higher from the windage tray bottom now). The crank received a light knife-edging and there seems to be a killer balance on the rotating assembly.

What engine oil is the best for hard driven street machines? The more I drive it, the more I find it impossible to keep my foot out of it. And with the cost for the resto - I'm certainly not going to scrimp on engine oil.

Also, I'd be interested in any info regarding high quality auto trans oil. The TH350 Jakeshoe built is holding up like a champ - just like he said it would.

Nearing 200 miles, I want to go ahead and change the breakin stuff - engine, trans, rearend - and get her ready for spring. BTW, Currie recommends only using Torco 140-85 with their limited slip additive so I will stick with that.

As always, muchas gracias for your help!
 
Save
Like Like
#2 ·
From what I've read, Mobil 1 and then Red Line for the even higher end stuff. Not sure on the additives in RL for a street motor. It's hard to "test" oil as a regular guy. So it's mostly opinion. Mostly you'll get guys that will say I've used "X" and never had a problem. I have seen an article by a Phd that worked at UCLA so he had access to a lab. Didn't do a spectroscopry(sp) test, just viscosity and a few others. He tested Mobil 1 on his personal motorcycle. Apparently the gear box is hard on motor oil. Anyway, his testing showed Mobil 1 to last about double the conventional oils in his bike. Which was only about 1500 miles for the Mobil 1. Not enough to change color to bad I'd imagine. He tested against oils advertised to have aditives for gear boxes too. One the other hand, I know a guy with 100k on his bike only using Castrol GTX. Go figure..
 
Save
Like Like
#3 ·
Once you get some more miles on it I would recommend Amsoil as the best of the synthetics.
Mobil 1 is also good but I feel from the testing I have seen the Amsoil is one of the best.

Go here, read the free info & buy the book, it will tell you more than you ever wanted to know about oils

web page

Hers is another excellent site on oil:

http://www.bobistheoilguy.com/
 
Discussion starter · #4 ·
Thanks, guys. The number of synthetic proponents is interesting, and is part of what I am trying to discern. Some old schoolers say no synthetics and site metal porosity and tendency to gunk and all kinds of mumbo jumbo. At the same time we got some of the top independent engine builders in the country (like Lewis) saying synthetic. I'm gonna go another round with Castrol GTX and then switch to Amsoil.

Best,
 
Save
Like Like
#5 ·
I use castrol gtx, mine runs fine, and is always clean inside, and it has'nt blown up "yet".
 
Save
Like Like
#6 ·
I can say for a fact that Mobil 1 will not gunk your fresh motor up. 100K on my truck. Zero sludge with 5-7k change interval. Or about twice a year.
Amsoil can be harder to get. Need a distributor or some such I think. Not that I'm knocking the oil itself. Heard good about it too.
Synthetics don't "boil" off like conventional. So less junk is left behind.
Have head a few unkind words about Castrol Syntec though. May have just been the early stuff. Got pushed on the market too fast to compete with Mobil 1. I do believe that none of the syntec adds will mention Mobil 1 in their test data mumbo jumbo. "Ours out lasts all these others oils" blah blah blah. Notice none of them have a "M" for an abreviation.
 
Save
Like Like
#7 ·
I have had very good luck with Castrol GTX for conventional and Mobil 1 for synthetic. As was mentioned before both of these can be had just about anywhere.
 
Save
Like Like
#8 ·
Amsoil first choice, Mobile 1 red cap (15-50) second. Stay away from the oils that have the sunbirst star looking thing that says safe for gasoline engines.
 
Save
Like Like
#9 ·
I just did the wife's '99 Blazer last weekend, 2nd change with Mobil 1, which followed Royal Purple at 18k miles. It has 50k miles on the 4.3, and nothing on the drain plug magnet. Yes, 2 changes, 32k miles between them. I've been following this guy's synthetic oil study, and from what I've seen when I drain the oil, it's still good. Took the Royal Purple to 18k miles, then 14k more on the 1st Mobil 1, and when I drain the oil, it's amazing that it still looks good, not too dark, definitely not black like a regular oil. I'm pretty much sold on Mobil 1. It's cheaper than Royal Purple by about $3/qt around here, too. Check the link, it's kind of a long read, but a good one. The guy samples his oil every 1k miles, sends it in for analysis. First round with Mobil 1, he didn't even have to change the filter until 12k miles, per the analysis results. Amazing.
 
#10 ·
A couple quick questions for you guys.....
I was told to use straight 30 weight oil during the break in of my 333. Is this what I should use? Also will it matter if I use that and then start using synthetic oil? I've also been told that you don't want to switch between natural and synthetic oils, but I would only be using the 30 weight for the break in and maybe a hundred miles or so. Last question, what are the benefits of using synthetic oils? Thanks a million guys.
 
Save
Like Like
#11 ·
Straight 30 is what I've always used to break in my motors, never had a problem with it. If you used moly based lube for the cam, though, you should change the filter after the first 50 miles or so, as I've heard the moly lube will clog the filter, open the bypass valve and then you won't be filtering your oil. I haven't heard the same about synthetic cam lubes though. Then again, I've never cut open a filter after break in.

As far as switching to the synthetics, just do a thorough job of draining the oil, any residual dino juice will not hurt the synthetic oil. Maybe thin it while hot with a can of motor flush, make it drain more thoroughly, while hot. My neighbor switched to synthetics in his '03 Softail a couple months ago. Bought twice everything, changed engine, trans, and primary oils to synthetics, rode around for an hour, then changed it all again, for a thorough flush. :confused: Overkill if you ask me, but he's like that. He also says he's gonna change it every 3k miles.
Image
 
#12 ·
For dino oil, I prefer the "fleet" blends like Pennzoil 15-40.
 
Save
Like Like
#14 ·
Well I spent many years liking penzoil, but then switched to Mobil 1 synthetic. Now there are 2 oils I will use based upon my experiances at work. Rotella 15w40 and Mobil 1 0w40 (european oil difficult to find). I have taken apart engines to fix oil leaks with over 100,000 miles on them that are absolutely brand new looking inside. They don't even have a yellow tinge on the insides. I mean no sludge coating of anykind on anything. That was from using Rotella 15w40 at 7500 mile intervals.
Mobil 1 will leave everything covered in a yellow tinge, but to be fair these cars are going anywhere from 10-13 thousand miles on an oil change now.
 
Save
Like Like
#15 ·
Inresponse to the break-in oil engine question. When I picked-up my 496 from Speed-O-Motive on Saturday, I was told to break-in the cam with straight 40. Change it, then run 20W50 for the next 500 to 1000 miles. Change again and run whatever I want. I asked about 30wt because that is what I always ran, but the machinist said they prefer their customers use the straight 40 for the extra cushioning during break-in. Any thoughts on this?
 
Save
Like Like
#16 ·
We have used most every oil out there in our stockcars and the final choices were castrol synthetic (absolutely incredible stuff) and valvoline 20w50 for mineral based oils, straight 30 for break-ins.
 
Save
Like Like
#18 ·
Good to hear. I'll be using 30 weight oil for the break in then, and mobil one for the usual. Do you guys recommend a certain weight for the mobil one? Also, how often would you guys recommend changing the oil if I used the mobil one? Something like every 5k miles? I don't want to try to stretch out the oil changes, but rather am just looking to lube this engine the best way possible. I had some serious lubrication problems with my last engine and I DON'T want it to happen again. It required a rebuild and a few thousand $$.
Image


What do you guys think of Prolong? I've heard that it lubricates BEAUTIFULLY. Would this stuff be likely to cause sludge in the engine? It's also like $20 for a quart, but i guess that's all you need to put in with the rest of the oil.
Thanks again guys


I'm glad to hear the replies since I will be getting my engine back tomorrow!!
Image
;)
Image
I'm slightly excited :D
 
Save
Like Like
1 - 18 of 18 Posts
You have insufficient privileges to reply here.
About this Discussion
17 Replies
13 Participants
Last post:
71chevy0192
Team Chevelle
posts
5.3M
members
131K
Since
1998
A forum community dedicated to Chevrolet Chevelle owners and enthusiasts. Come join the discussion about restorations, builds, performance, modifications, classifieds, troubleshooting, maintenance, and more!
Full Forum Listing
Explore Our Forums
Bench Racing Performance Engine Chevelle Tech Body Shop