I_am_imprezed

I've read that you are not supposed to use a synthetic to break a motor in. Does anyone know if this is true? Also if i am using a mineral oil to break it in, which should i go with? GTX? and what weight?

beentherebaby

Most oil companies do not recommend using synthetic oil until a new engine has 3,000-5,000 miles on dino oil. Note that I said "most" oil companies. The obvious reason is the rings need to seat into the cylinders. I've seen many a new Euro engine with a certain synthetic oil as OE fill that was smoking and consuming a qt. of oil in ~600 -1000 miles because the OE fill was synthetic instead of dino and the piston rings were not seating in well.

If it were me I'd use something like Castrol GTX 10W-30/40 assuming that your engine has std. bearing clearances. Many people have differing views on motor oils, engine break-in, etc.

944Sknight

Porsche rolls off from the factory with mobil synthetic. What does that tells you?

running_cold924

that's not what your 944 rolled out with...(your talking about a ~25 year difference here)

brad penn has a nice break-in oil. just remember to change the filter as well when switching from the break-in oil.

I_am_imprezed

How long should i keep the brad penn in there?

running_cold924

well the break-in i did for my jeep(4.0 to 4.6 stroker build) to seat the cam was 30 mins at 1700-2500rpm. let it cool and drain the oil, replace filter. refill with new (i'd still run brad penn)

should be fine, drive s normal, but obviously keep the revs a little lower.

beentherebaby

See post #2 about high oil consumption and smoking on "certain" new engines filled with synthetic oil... Also be aware that an OE oil fill is not the same exact oil formulation as over-the-counter oils, in spite of what some people claim.

marky522

I agree with the idea of using dino oil for break in to seat your rings etc, but I think the 3000 miles etc is excessive, its broken in shortly after startup.

And yes Porsche comes off the assembly line with Mobil One 0W40 Full Synthetic, no "Special Formulation"... And There are VERY few cases of high oil consumption on current generation P-Cars...

HTH

Mark

I_am_imprezed

so is brad penn overkill? if so is 10-40 GTX good to start off and switch to a full synth prob 20-50 for next years track days.

M758

I use a 20W50 dino oil like VR1 for break in. For a track car break in for me is about 1 day. First session is break in run (alternating full throttle through out the rev range and engine braking for decel to backpressure the rings) and then I run a normal day. Change the oil for my normal racing oil at day's end.