eep4life

what oil is recomended for the initial start up... i know later on i can switch over to a syn bled or full but i thought i read on here that a specific oil is used... whats it called and what type should i use.. ie 5w 30 10w 30? oh and how much... and instead of posting another thread... not counting whats already in my torque converter... how many quarts of trans fluid do i need to fill up my C4 auto trans?

109jb

I use Valvoline 10W30 mineral based oil.I break in by warming the engine up and then driving normally except I intentionally perform several quick speed bursts followed by quick decelerations. Country roads work well for this. I try to do this for at least the first 500 miles (As much as is practical.). Then change the oil. I use mineral oil for about the first 2000 miles and then I run sythetic. I'm not a professional engine builder, but I have rebuilt about a dozen engines without any problems using this procedure. I'm sure there will be varying opinions on this though.

390bigblock1

i used royal purple 10w30 in the winter and right after i got my engine rebuilt and in the summer i used royal purple 10w40

Starfury

It is VERY IMPORTANT that you use 15W-40 diesel oil for break in!!!!!!!!!!! I cannot emphasize this enough. Use something like Shell Rotella T, Chevron's Delo 400, or Valvoline's Fleet 15W40 (or the Napa brand stuff, which is the same).

In the past 5-10 years the EPA has cracked down on oil manufacturers to cut zinc dithiophosphates and manganese out of most street oils to reduce pollution. Likewise, in the past 5-10 years a lot of people have been wiping out flat-tappet camshafts during break-in or several hundred miles down the road.

In addition to being hazardous to the environment, these chemicals react with the metal friction surfaces (ie. cams and lifters)in engines to form a protective boundarylayer should metal to metal contact occur. This isn't much of a problem in newer engines with roller camshafts, but it's a big problem for those of us running older engines with flat-tappet cams. It's so much of a problem that several magazines have put out articles about it, and Comp Cams even sends out a flyer with every cam they sell explaining the problem.

Diesel oils still have these chemicals in them, and therefore make great break-in oils. They prevent metal shearing should metal to metal contact occur during break-in, the most crucial wear period of the cam. There are also additives you can buy from the cam mfg's to add to standard oil, but diesel oil works just fine.

Some of the off-road racing oils like Royal Purple and Redline also have the proper chemicals in them, but you shouldn't use synthetic oil until 10k or so miles. Synthetics are actually so good at lubricating that they don't allow the friction surfaces to properly wear into eachother.

jcomp

I've heard that Rotella will soon (or might already have) lower the ZDP levels in the oil. I'm not sure about the other brands of diesel oil.

A lot of people also recommend using GM EOS (engine oil supplement) for break-in.

Starfury

Erm, yeah, I think somebody told me that last month as well. I also heard GM doesn't sell the EOS anymore. Comp Cams sells bottles of their stuff though.

jcomp

The EOS was discontinued, but they changed the part number and are bringing it back: http://www.gmpartsdirect.com/results.cfm?vc=1&wtype=v4

I didn't know it wasn't available yet, though.

Sam's Club sells Rotella in 55 gallon drums. I bought one a few years ago but it's since run dry. I wonder if it's too late to stock up on the good stuff.