Oil & Flat Tappets

[Hog]

Originally Posted by Dynomite

Just run Amsoil 10w40 and be done with it. Get it delivered to your door

I do what Marc Haibeck tells me to do except I kind of like a quicker oli filter drain back before removing oil filter (Mobile M1-207). I do not notice any lag in oil pressure on start up

Even in the 3rd year of the SBC, the 1st year of the 283 isnt the "tightest" of sealed engines? ANy issues with the rope main seals?

Certainly something to consider. Thanks.

Amsoil is available on the shelf here at Canadian Tire, $21.00 a liter(quart).

[Mystic ZR-1]

10w40, 15w50 etc...
How come GM said 10w30?

[Jim Nolan]

I don't recommend any oil. That is a personal choice based on info. available. I can tell you when I bought mine in '98 it had cam chain rattle about 1 in every 4 starts. I suspect it had dino oil all it's life. By the second oil change of Mobil 1 it went away and I haven't heard the rattle since. I don't think it was so much Mobil 1 as it was a synthetic over dino oil. As for why GM recommending 10w-30w. I'm sure there are alot of opinions on that, so I won't go there.

Jim

[Paul Workman]

Originally Posted by Mystic ZR-1

10w40, 15w50 etc...
How come GM said 10w30?

At the time the LT5 was introduced, phosphorus and zinc in the API SG and later the SH was 1200/1300 respectively (C-link).

If there is a synthetic 10/30 with the phos./zinc at the 1200/1300 levels, then it might rise to the top of the recommendation list for today's LT5 oils However, shopping around, there doesn't appear to be a 10/30 that does, or if there is, it isn't exactly advertised very aggressively, apparently.

So, reasonable substitutes are the AMO 10/40 (the 10W... part is the key with regard to cold viscosity) with 1200/1300 and Mobil 1 15/50 also has the same ppm of the good stuff. And too, the Mobil 1 High Mileage 10/30 comes close and might be fine too (and is what I bought for Jim and Nancy's car when the oil filter sprung a leak on the Mountain Run.)

Since I don't drive much in winter due to the salt, 10/40 is fine for summer, I recon. And, when I buy it by the case, the price for AMO 10/40 gets down around $7/qt, changed every-other year (under 5000 miles as a rule).

P.

[Gunny]

in reply to Paul w/reference to Marc

I also use Amsoil 10-40 ... in my part of Georgia it's always warm or hot with some rare cold spells so 10-40 works well. Similar to Paul, I change oil every 24 months with at least 2, if not 3 filter changes in between oil changes and topping up as necessary. I suspect the Mobil 1 High Mileage 10-30 is probably OK for most applications but would really like a "go ahead" recommendation from Marc and the other engine builders. With a "thumbs up" for the M1 high mileage 10-30 I would probably go back to that simply because it's readily available at WallyWorld.

[secondchance]

I have been using off the shelf Mobil 1 since I bought the car in 2000. Of course we have gone through a few generational change of Mobil 1 which I was not aware of 'till about 2-3 years ago (at the time I had about 110,000 miles). For the last 2 years I added 1/2 bottle of ZDDP until about a year ago, switched to Mobil 1 for high mileage cars.
For what it's worth, cams and flat tappets were all in excellent shape after 140,000 miles. General consensus I have been hearing is that LT5 with relatively short lift and less spring pressure is less susceptible to cam wear compared to high performance OHV V8s.

[Paul Workman]

Originally Posted by secondchance

*...General consensus I have been hearing is that LT5 with relatively short lift and less spring pressure is less susceptible to cam wear compared to high performance OHV V8s.

YES, and less valve weight too. But on the other side of the ledger is the fact pushrod motors are rev limited substantially lower than the LT5, and cam chains are significantly longer on the LT5 than the average single cam pushrod motor.

That said, a while back there was a survey to see how many had ever hit their rev limiter. I was astounded by the number of replies that not only never hit the rev limiter, but putted the LT5 around below 6000 rpm! I suppose Johnson & Johnson BABY OIL would work just fine in that case! AND, they run the risk of their man card being permanently revoked up here in FBI country!! (Just kidding).

[We Gone]

http://www.mobiloil.com/USA-English/...duct_Guide.pdf