My 2000 Maxima has just went over the the 180K threshold, and I'm wondering what type of oil I should be using. Ever since I bought it in 2007, I've been using synthetic 10W-30 of varying brands. Lately switched to Pennzoil Ultra
http://www.walmart.com/ip/Pennzoil-U...-5-Qt/14958685

When I went in to change my power steering hose two weeks ago due to leak, my mech informed me of possible leak engine bay. Changing gaskets would have been an all day process and cost me at least 350 in labor, so I passed for the moment. Added a half quart of remaining Ultra that I had in truck. However he opined that I should be using a higher viscosity oil since my car was so old. Is that true? Should I move up to 10W 40 or something higher.

Appreciate your opinions.

 

Should I be using "high mileage" oils since they have sealant conditioners?

 

A high mileage oil wouldn't be a bad idea. They have additives that help swell gaskets and seals. Generally they are a semi-syn so you still have those benefits. Why the 10w30? Are you always above freezing where you live? IMO I would run 5w30 high mileage for a few changes. It will be easier on startups and you will see if you have any luck slowing those leaks down.

Edit - Just noticed you are in Texas. Now I understand the 10w.

 

As a force of habit I always switch to high mileage oil whenever my cars reach 100k miles.

 

For the VQ30DE Valvoline MaxLife has shown very good results in wear. I used to run that in my 96 maxima. MaxLife is also available in semi-syn or full-syn. I used the semi-syn (red bottle) since it was much cheaper and still provided good protection. I drove that car very hard and I sent a few samples for UOA (used oil analysis). The results were good every time. You just have to know what your driving does to the engine and adjust your oil change interval according to that.
I drive pretty hard so my oil is usually shot in about half the miles/time that most people do it in.

 

I've been running 5w30 MaxLife (either full syn or blend, depending on sales) for several years now in my '01. Never had a single problem. I use Pure-1 filters, too.

More important than the brand of oil, is how religious you are about changing the oil. I've tried to stay in the 6000-8000 mile range for changes.

 

I run rotella t6 0/5w-40 and it cut my oil consumption by half. also run the pure one pl1469 as its twice the media as the 610 but only fits if you have the oil cooler for the 5.5

 

I hope you have done some UOA's with that long of an oci. With my driving there is no oil out there that lasts past 6k miles

 

I've never done a UOA and don't plan on it. IMHO, UOAs are useless geekery.

 

Ummm. . . ok. . .

 

Roll your eyes elsewhere. I've never seen any practical use for a UOA on a passenger car.