MT Oil consumption failure
 

Just got off phone with Nissan engineer regarding questions I had regarding oil consumption and catalytic convertors. I had a short block replacement due to oil consumption.

His responses:
Oil consumption failure is greatest in manuel transmissions due to down shifts above 5,000 rpm creating negative vacuum*. Oil viscosity break down does not necessarily begin between 240*F - 260*F. So no need to worry, you are under warranty.

Catalytic convertors are not necessarily effected by six quarts of oil burnt over them. Maybe effected. Diagnosis: you are under warranty. No need for replacement. I pointed out my first smog check is at four years, one year after warranty. Silence followed by "you are under warranty."

Q. How does the car run now?
A. Just as well and well as when it burned one quart of oil every 500 miles. Only less smoke out the tail pipes.

* My car failed before 500 miles in all likelihood during break in, as I was down 3/4th quarts. Six quarts by 2,900.

I'm not sure what he means by that. He's implying that people with oil consumption issues downshift into high RPMs frequently? Or does doing a few high RPM downshifts then induce a persistent oil consumption thereafter?

Your warranty on the catalytic converters is not necessarily over at 3 years - by Federal law, a manufacturer's warranty is required for all new vehicles covering smog pollution reduction equipment for a minimum of 8 years or 80,000 miles, whichever occurs first.

Well what is the SRM for then? :confused:

i down shift my honda at near redline frequently and yet oil consumption is minimal.

on the z i downshift quite high but around 4-5k. my oil consumption is not measureable... im at 4k miles.

i too dont know wat the nissan engineer said.

did he start making up acronyms by any chance? :D

Who is Manuel? Were our transmissions made in Mexico?

no, only the designer was mexican. ;)

:bowrofl::roflpuke2:

:bowrofl:

Stop that..... This is a good info thread.

:icon18::bowrofl::roflpuke2:

Ok guys. Let's not be ethnic; else you guys get banned. :)

OP,

Does your rebuilt motor still burn oil? How much?

:wtf2:

I don't even know why I bothered clicking on this post.

My engine failed beore 6000 kM. They did the short block replacement. They said there was some problems in the early models, but the new block had a fix for it. Well I checked the oil and after 3000 Km it needed more. So I don't think there was a "fix". Interesting to see the "vacume" theory. In my case I doubt that happens very often.

cant finish Im at work
 

He's implying that people with oil consumption issues downshift into high RPMs frequently?

He said Nissans' observation is that people with MT down shift more than those who drive AT's. Higher revolutions and making the engine work harder wears out faster. (Yeah no kidding). So I asked him about the SRM and should I not use it during break in. Answer: The SRM helps with engine break in and smooth shifting.

I am not 100% sure he was actually a real engineer.

How much more is the question. OP was using 6qt every 2900 miles. That is the very definition of excessive. 1- 1.5qt every 3000 miles would not bother me in the least.