What oil weight & brand is everyone using?
 

What oil weight & brand is everyone using in their 4.3? I have been using Mobil1 5W30 synthetic since day one and have issues with seal leaks and now the oil lines. BTOG are advising me to go to a Mobil1 10w40 High Mileage oil or other brand but stick to a 40 weight. I wanted to see what everyone here is using and their experiences. thanx

RE: What oil weight & brand is everyone using?
 

I Use Castrol 5W-30 Regular Dino Oilin My Truck its a 97 Blazer, Did it come from factory with Synthetic or Reg Dino Oil. Synthetic is really thin and causes leaks on engines not designed for it so if you switched its too late bc you cant go back.

RE: What oil weight & brand is everyone using?
 

Who on BITOG recommended a 40W? Unless you have a reason (consumption, etc.) I would not recommend it and I am a poster on BITOG. If you have a lot of miles (over 100k) you might consider a 'high mileage' oil, butI say stick with 5W30 or 10W30.
To BlazinMike89:
It came with conventional oil, not synthetic, in the engine. Synthetic oils are not 'thin' by nature. A 5W30 is a 30 weight oil that has the properties of a 5W oil when cold whether it's synth or dino. The myth of not switching between synth and dino is just that - an old wives tale. Feel free to do so without fear.

BTW, I use Havoline 10W30 in mine.

RE: What oil weight & brand is everyone using?
 

Yea i understand That, I was going to Switch to Syntetic but Heard stories of oil leakage and seeping out thru seals and gaskets. So I'll just stay with the 5-30 Dino Oil That I Use, I Havent found any reason to switch. I Thought that Synthetic had more lubricity than Dino Oil and if used then switch back it would sort of under lubricate the engine

RE: What oil weight & brand is everyone using?
 

I have nothing against synth especially when used in the correct applications. I use dino because our engines are not high temp, high stress machines and are not at all picky about anyname brandoil. If you want to switch to synth, it won't hurt a thing, and you can go back to dino if you choose to later. What you may discover is that the synth might soften any engine seals that might have hardened, causing a temporary leak until the gunk is flushed away in an oil change. If I were to use synth, I think it would be Pennzoil Platinum.

RE: What oil weight & brand is everyone using?
 

False. Plain and simple. The thickness of the oil is the viscosity rating and the range it can fall in. Some oils are at the low end of the viscosity range for a 5W30 and some are at the high end. Same thing for conventionals and synthetics. It all depends on the manufacturer of the oil. Mobil tends to fall into the thin spec for a 5w30. Pennzoil is more in the middle.

I would not recommend going to a 40 weight oil.

Where are your leaks (other than the lines)?

RE: What oil weight & brand is everyone using?
 

Swartlkk

Theonly current leaks areat the oillines (knock on wood) but you know of my past crank & pan seal leaks;and I'd like to try and not replace the lines right now, as money is really tight right now since my wife was in an accident and totalled her Malibu. I was considering using Mobil 1 High Mileage 10W-30 HM. It gives you a ZDDP level of 1000, HTHS is on the order of 3.6, 100C cSt close to 11.8, it does have the added seal conditioners, and great cold pumping. I'm trying to save every $1 to get a coolant flush this spring as I am nearing my 5yr Dexcool date in August. What do you think? 29K original miles!

RE: What oil weight & brand is everyone using?
 

5yrs. If everything looks good, just drain and refill with either premix or mix it yourself with distilled water (saves money). I would use the Zerex extended service coolants.

RE: What oil weight & brand is everyone using?
 

Thanks on the Zerex, I was leaning towards that or Peak Global Lifetime. What's your opinion on switching to Mobil 1 HM?

RE: What oil weight & brand is everyone using?
 

When HM oils first came out, they were a reason to charge more money for something that was not a whole lot different than the regular stuff. Now, with some of the additive packages, they can be good for a loose engine.

As far as curing your leaks, if the lines are the only thing leaking, a 10w30 would be better than a 5w30. In that respect, I do not know if a HM oil will be any different than a general use oil.

RE: What oil weight & brand is everyone using?
 

Well I don't care about brand, weight, or cost. I just want an oil that I can use for approx 7500 miles with a fair amount of idle time, and keep any leaky lines and past seals in check. So I am just looking for some expert advice from fellow 4.3 users/rebuilders, so if there is abest option based on what ive stated, please advise.

RE: What oil weight & brand is everyone using?
 

The only way to know if an oil can go 7,500 miles in your vehicle is to have a used oil anlysis done by a firm such as Blackstone Laboratories, but I doubt if any conventional oil will do that.Based on your stated goals, I would recommend Motocraft High Mileage Synthetic Blend Motor Oil.

RE: What oil weight & brand is everyone using?
 

Riddle, I have read through hundreds of UOAs' and know how various oils perform on alike Vortec engines. While Motorcraft is a great oil and has the UOA's to show it, I think there is a better option for me by way of Penz, GTX, MAxlife, or Mobil 1 HM. I will more than likely try the Mobil 1 next OCI since I can rest assure there wouldn't be any oil chemistry compatibility issues with remaining oil form the current fill. I think I will start running 10W30 in the summers.

RE: What oil weight & brand is everyone using?
 

BlazerSS,
You asked for a best option based on what you stated - I gave you one. If you already had oils in mind, why didn't you just say so.I won't waste any more of your or myown time. ;)

RE: What oil weight & brand is everyone using?
 

riddle if you actually read my posts you would have seen that I mentioned the Mobil HM oil as a possiblity. I was just looking for reallife examples of what others are using and have used to stop or keep leaks in check. Im no chemist, but I know that the makeup of certain oils is better for certain engines. I figured people here would know better about the internals of the 4.3 & our seals and gaskets and what migh work best to conditon them based on know problems. thats all.

RE: What oil weight & brand is everyone using?
 

Any oil that is more than 50% synthetic can be called a synthetic oil. The trick is to use an oil that is 100% synthetic. Forget about the myths of leakage... I did. Run your first synthetic oil change as a normal one. Then change your filter every 5000 miles and the oil every 10000 miles. Two filters for every oil change.

RE: What oil weight & brand is everyone using?
 

I still run regular dino oil. Oil changes about every 4000-5000 miles.
Castrol or Valvoline 5w30 and Fram oil filters.
Current truck has 175,000 miles and no engine troubles. I bought it with 27,000 miles on it.
Actually that is what I run in all my vehicles (currently 5) that I maintain.

My Astro van had 286,000 miles on it before Ihydroplaned into a bridge and totaled it. It ran as strong as the day I got it with 60,000 miles on it. And it burned oil during start up, leaky valve guides. I never had any trouble with that engine either.

you can fork out the money for the synthetic, however most gas engines are designed for 150,000 miles before needing a rebuild. Anything over that is due to good maintenance. I plan to hit 300,000 miles before I drop in a V8. [sm=burnout.gif]

edited to add, I too have leaky oil lines and dont really care. they have been leaking for a long time now. Every summer I pressure wash the oil debris off. Maybe one of these days I'll fix them. Maybe not.

RE: What oil weight & brand is everyone using?
 

I use mobil oil and filters never had a problem. ( 98 chevy blazer and 97 chevy tahoe). I use 10 w30 in winter and 10w 40 summer and also add lucas oil stablizer. I have used the same oils in a 91 chevy blazer with over 250 thousands miles on it and it used a very little oil between changes. same with both my trucks now. but my blazer has a new oil leak comming from a oil line the goes to the oil filter in the front under the grill 98 blazer has over 130 thousand on it first oil leak since i owned it going on 5 years.

RE: What oil weight & brand is everyone using?
 

if i can jump in real quick? will a 40 weight help limp and engine with wearing rings along for awhile?

RE: What oil weight & brand is everyone using?
 

You can try it but if the engine is smoking due to badly worn rings there is no cure that comes in a can.

No one has said anything about Royal Purple yet lol