After reading all the posts, I didn't quite get the answers I was looking for, so wondering if you people could provide some insight.

the scenario:
I'm driving a '99 infiniti i30 w/ ~55k miles on it
I live in VA
My trips are usually a 70city/30highway driving, w/ city driving between 4-11 miles.
My driving usually sees redline everyday.

I was going to use 5w-30, and keep the change intervals at probably 8k miles w/ no oil filter change. I was wondering if it's safe to go higher then 8k, and what interval i should change my oil filter if i keep the oil in longer? any other tips welcome

thanks all

 

hmmmm, where's Bill?

Well, I wouldn't suggest going over 6k on any type of oil. I would also recommend AMSOIL or Royal Purple oil instead of Mobil 1. 5W-30 is fine.

 

Does your drive to work involve a trip to the track every day?

 

if you go with mobil 1 you might want to put some oil additives in there. mobil1 has no detergents so that's about the only draw back to such a good synthetic. I just stick with the Valvoline Synpower. Best of both worlds and you're still getting a full synthetic.

 

I personally use Mobil 1 5w30 with a Mobil 1 filter. Both get changed every 7K, which is usually about every 4 months. Started doing this with 37K on the car. Now at 62K, one year and two months later. SWo many miles in so little time.

 

Empirically, my baseline oil results in my spreadsheet on both oils back up your claim.

However, in the real world where people use the products, Mobil 1's SuperSyn formulation seems to remain more stable from a viscosity (almost no thinning on SuperSyn) and TBN standpoint than Valvoline SynPower. SuperSyn's lack of thinning over several thousand miles tends to allude to its better shear resistance and overall stability compared to SynPower, which has a relatively high initial viscosity but does thin down to the low side of a 30 weight oil.

I was very skeptical of the new SuperSyn formulation, but it looks to be the best Mobil 1 synthetic yet based on real world results.

Both oils are good choices.


Saying Mobil 1 has "no detergents" is false. Who gave you that idea?

 

Given your intentions, this is what you should do:

Use a 10W/30 synthetic.

Use a STP S6941 oil filter.

CHANGE the oil filter at 4k.

Go 8k intervals.


The very first thing you should do is have your current oil analyzed to see where your engine stands now, as you may have elevated wear metals that necessitate you going 3k intervals a couple of times to "flush" out any extranneous particales. Shoot me an e-mail or follow the link in my sig if you have other questions.

 

sorry, i meant mobil 1 has fewer detergents then synpower. i'm quoting from palmerwmd on NICO..he has an unending wealth of oil data for some reason.

 

Valvoline Synpower is a true "full" synthetic. It is a Group III oil just like Castrol Syntec.

From the MSDS for it:

PETROLEUM HYDROCARBON 64742-54-7 52.0- 62.0
ZINC COMPOUNDS 0.7- 1.4

 

Hi, Bill!

 

 

so then what do you guys think about Royal Purple? Is it a waste of time money?
Would you prefer Royal Purple, Mobile 1, or Valvoline Synpower?

 

Man its nothing but open roads out here! I redline all day long!!
One of our most traveled roads in this area is I95! go figure!

 

[i]Or

 

Thanks Bill, appreciate all the info. I was going to try and skimp on having the oil analyzed, but it's looking like more of a necessity. I still have about another ~1k miles to go before my next oil change and will have it analyzed at that time, we'll see how pennzoil holds up in 3k.


I've grown fond of that sound at WOT (darn intake). I don't ALWAYS floor it though...I'll get on the pedal for a few seconds maybe once or twice a day. So it's not like I'm drag racing everywhere I go.

EDIT: btw, how much are you guys paying for AMSOIL?

-John

 

It's always good to see where you stand initially and how your vehicle has faired with your current drain interval habits and choices in oil and oil filter.

If you can't get a sample kit from Blackstone Labs when you need it, let me know a few days before your oil change and I'll ship you one of mine personally. To order a sample kit, go here:


http://forums.maxima.org/showthread....hreadid=100060



E-mail or PM Mark (member iwannabmw) for Amsoil prices, as he passes along his discount to .org members. My guess is $4 to $5 a quart including shipping.