i got a 1994 z28 with a 111,000 miles what kind oil do you guys recomend and if its a big deal what kind of oil filter should i use thanx

 

i use sae 30 in the summer and go lighter in the winter, for a filter i use ac 1218.

 

Been discussed before and there is no good reason to go to a straight weight oil.
Depending on exactly what brand of oil sometimes you want a 40wt and sometimes a 30wt. in the LT1 some of the proven through analysis favorites are Castrol Syntec 0w-30 but is has to say "made in Germany" on the label this is actually a fairly thick 30wt providing outstanding results to way way past what most people will leave it in the sump. If Mobil is your thing DO NOT use the 5w-30 or 10w-30 everyone MISTAKENLY thinks is good for this motor, they are not they are better suited to the new Furds and Hondas specing 5w-20 as the M1 30wts barely registar as 30wt, the 0w-40 or 5w-40 are just right though. Amsoil 30wts all seem about right and tend towards the thick end of the 30wt range, all those mentioned sofar should be safe to leave in long beyond 3K provided you drive the thing a decent amount and the air filtration is good. If dino is more your thing it is tough to say exactly what to use other than maybe avoid 10w40, what they need to do to make a dino span that range is not a great thing though it is not as bad as it once was, probably stick to 5 or 10w-30 if going dino and keep the intervals say below 4K. Right now I am waiting on results for Rotella T synthetic 5w-40 I have in my LT1s right now, it is a less expensive synthetic and marketed more for diesels but is gas rated and proven time and time again to just be a good reaonably priced oil, once I get the test results back I will know more about how it is doing in my LT1s. For more reading and much better info that you will ever get here on oil try http://theoildrop.server101.com/cgi/ultimatebb.cgi

 

w/ SAE 30 and 20w50 my car has 25lbs of oil pres at 900rpm hot. sounds like a good enough reason to me.

 

I've got good oil pressure (40 on startup, 25 idling hot, 50/60 at high revs) running M1 10w30 all year long.. I use the K&N filter.

Why do the additives to span the 30 point range on a 10-40 or a 0-30 make a big difference on the dino juice but not on a synthetic? In either case, the additives won't be OIL, right, so in either case, the additives should reduce your lubricating ability, I would assume...

It does make sense to me that maybe since a synthetic like M1 is better to begin with, you wouldn't start to notice the loss of lubricating ability, or increase in sludge byproducts from breakdown from the additives as fast.. but it would seem that the loss is still there to some degree...

Sort of like how you wouldn't really notice a really smart person being affected by Alzheimers as quickly as a less intelligent person, because they have more cognitive ability to begin with, so they don't reach that baseline level as quickly.

These are assumptions, and maybe they're wrong, but if they are, I'd like to know why.

 

Those who chose to remain ignorant ignore the link I posted, those who want to learn and learn a lot click away.

 

I agree, BOBISTHEOILGUY is the best oil site out there. Period. Also, do a search for the username Patman in the LT1 section. I HIGHLY recommend reading everything he post as he is not only incredibly knowledgeable on the subject (for LT1's & LS1's or other cars), but he has always tested many different kinds of brands in his cars and others through oil analysis test...Hey, the results don't lie and are good enough for me...

BTW, I bought my '95 Z28 with nearly 109,000 miles on the clock which had just used regular standard dino oil its whole life...I ended up putting in the German made (it's the green formula; although the newer brown stuff appears to be testing just as capable) Castrol Syntec 0w30 (more of a true 40w FYI) in it after 111,000 miles and I will not look back! I'm very impressed by it so far after using it compared to the Mobil 1 5w30 I first put in it. Again, do a search under Patman's username as well as the German Castrol Syntec. Also, I would use M1 0w40 or 5w40 in my LT1 if I couldn't find what I'm currently using. But I'm sure the new M1 extended performance oils that just came out would be a great choice too.

Best oil filter that has shown the least amount of restriction at higher rpms seems to be the K&N per testing. Again, I use it along with the GCS in both my LT1 & LS1 and wouldn't use anything else.

This is definitely a very sensitive subject to some out there, but read like the guy above mentioned and you'll have a good idea of what might be best for YOUR car.

Mike

 

Mobil 1 0w40 oil, ACdelco filter will be fine.

 

id like to see the difference in oil temp at 6000+rpm for a given amount of time w/ these 0w oils. i can tell you that the SAE 30 and 20w50s stay at about 200 degrees and the thin oils ive seen (5w's) have gone to around 300+ degrees. oil analysis is like balistics testing, only part of the equation.

 

I run Schaeffers 5w30 synthetic blend. Check it out.

 

Once at tempature they are 30 or 40wt so the 0w means nothing then. Besides you already made up your mind that you know everything about oil and don't want to try to learn anything so why bother asking questions? There are some good threads on there about oil temp changes with different oils as there are some members with f-bodies and Vettes that road race.

If you guys look in the UOA section, tonight I put up my UOA results for the Rotella in my Roadmaster, I go by DJ there.

 

put them in the fridge over night then heat it up to 200 on the stove the next morning. then tell me that.

put an oil temp guage on your car. then take it out an ream on it, a lot. then, put some straight 30 or 20w50 in it and repeat the process, then tell me which one has more oil temp. yes it does mean something.

i just stated what i run in my car, then you are the one who chimed in with "there is no good reason to go to a straight weight oil." so i gave some.

god forbid doing some of your own viscosity testing or watching oil temp. i crew on a road race team, well....its actually a nascar craftsman truck cup team....so what, what difference does make? but i do know what the oil does when it gets warm, and it doesnt get thicker.

and oil temp does make a difference, if it didnt all the cup teams wouldnt have a dry sump system w/ a 5 gallon capacity for a little 500 mile race. and if you dont think it doesnt make a difference on a 5qt wet sump oiling system, you are kidding yourself. these stock shortblocks arent built w/ low tension rings and lifters w/ .010 " plunger travel that allow oil restrictors to be used. use what you like, but when someone asks me what i use, dont criticize me when i simply tell them. i didnt start this argument, you did.

 

I've gotta completely agree with 93turbo5oh here.. and I eluded to this in my previous post.. 0w-x != x at high temperature!!! What 0w-x means is that the oil "lubricates" like a x weight oil at operating temperature, not that the oil IS THE SAME AS any straight 30 weight oil you can concieve of.

Lets examine that statement:

Firstly, lubricating like an x weight doesn't mean much.. the standards for a certain weight don't really relate all that well to how much actual engine protection an oil will give you. Case in point, the difference between synthetic and dino oils. There are 10w30 weight synthetic and dino oils, but most people wouldn't tell you that they are going to work the same in practice... You even went so far as to say that a certain 0w30 was more like a 0w40... further proving this point.

Now, knowing that saying an oil is a "30 weight" doesn't mean much on its own, we get onto the topic of HOW a XwY oil gets its title.

How does an oil have the properties of two different weights at two different temperatures? How does oil lubricate better at a higher temperature, when we know that one of the properties of pure oil is that it THINS at higher temperatures, and that it doesn't lubricate as well when it's thin.

The easiest analogy to use is a progressive rate spring. The XwY oil acts like this; the more force (temperature) you apply to the oil (to a degree), the stiffer ("pseudo-thicker") it becomes.

So how do we make oil have a progressive increase property instead of a progressive decrease property? Easy, we add things which have a progressive increase property. Additives bridge the gap between the two numbers in an XwY oil, and the larger the gap, the higher the concentration of additives.

But something important to be noted: additives don't lubricate; if they did, we'd be using straight additives rather than oil to lubricate our engines with.

Therefore, the higher the concentration of additives, the lower the concentration of lubricating oil.

There may be other side effects. One might be to lower the flash point. (Or, it might be to raise the flash point, depending on the additive).

I don't know enough about the additives in use, so I'm only speculating here about the side effects.

The point I am trying to prove is that a 30 weight oil IS VERY DIFFERENT from a hot 0w30 weight oil!

One thing is for sure, the 30 weight oil will have a much lower concentration of additives. (Additives which, if present, may or may not increase its flash point, may or may not increase its specific heat capacity, may or may not increase the amount of sludge created as a byproduct of breakdown, but most definetly would decrease its lubricating ability).

Anyway, 96capricemgr, none of us are experts here; both of us included, so please be constructive and respectful when contributing to a discussion. There are plusses and minuses to everything in this world, and we should always be able to entertain the possibility that there is merit to thinking in an alternative way. You don't have to agree, but at least respect other people's right to hold such an opinion, for whatever reasons they may have; but, of course, still provide your viewpoint to give them another way to look at it, especially if you feel it might help them to reach a better conclusion.

 

yawn...

 

"What 0w-x means is that the oil "lubricates" like a x weight oil at operating temperature, "
Exactly, since things like Xw-30 are so horribly why is it that the current best oil going for these things is Castrol Syntec 0w-30(made in Germany) we are talking actual wear metal content in daily driven and performance driven LT1s and LS1s.

What a Craftsamn truck needs doesn't mean jack here, we are talking about daily drivers and weekend toys, they need slicks that only last a couple hundred miles doesn't mean they are useful on the street even though we too need tires. Oil temps are not the whole story either a thin oil will do a better job of cooling parts and in doing so will get hotter itself as it takes in that heat to dissapaite it elsewhere. I know I am not an expert that is why I keep trying to post links to a wondeful resource but as the old saying goes "you can lead a horse to watter.............................."