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.