Just yesterday i changed the oil on my 00' Maxima on my own for the first time (got the car from my father and only just now needed an oil change) and noticed that there was old oil all over the front of the engine under the crankshaft pulley and all over the outside of the front crank position sensor, what gasket/seal could have worn out to have this happen?

I also noticed that on both of the belts i could see from there, i could see sort of like a white thread on the side of them. Is this an indication of belt wear? Thanks in advance.

 

Clean the engine and start monitoring for the leak source.

Chords showing through black rubber on belts is wear.

 

I would check post #8 as this sounds like your Oil Cooler is leaking. The only way to determine this is to Clean Clean and keep an close eye on it.
https://maxima.org/forums/5th-genera...oil-leaks.html


My 2000 Maxima GLE has undergone all sorts of work in order to STOP all Engine Oil leaks as I am a neat freak and don't like any Oil spills from my cars.

Took down the Automatic Transmission and replaced the Engine Rear Main Seal and since the Tranny was on the Floor, replaced all Automatic Transmission seals (all three).

Took down the entire Upper Oil Pan and replaced the U-Seals and of course the Lower Oil Pan Seal.

My Maxima has 221,516 original miles and now it doesn't drop anything and I don't have to worry of check the Engine Oil Dip Stick continuously.

Of course, replaced ALL Engine Drive Belts!

All this work was about a little over $1,200 parts and labor at a Pro Shop and believe me I could have done it but, why! The Pro Shop has lift and better tools so, I paid and it runs like new.

 

I’m also having an oil leak on my 2000 se not sure if it’s from the valve covers or rear main 247k

 

Believe me, that is the Rear Main Seal and it will only get worse and forget about using any additives! I used almost every possible additive and it only got worse.

Best of luck!

 

could it be the half moon gasket? Is dropping the upper oil pan accessible or trans needs to be removed?

 

Well, there are two half moons (frontal Engine & Rearwards).

I got an estimate for ALL items since the PRO Shop here in Orlando, Florida had to lower the Auto Transmission to replace the Engine Rear Main Seal then, it would be easy to lower the Engine Oil Pan and Upper Oil Pan assemblies to replace the Half Moons.

It saved considerable cost in Labor $$$ by doing it this way in my case.