Oil?

[eastbaysubaru]

Tough topic it seems. What oil should I be using on a car with 110,000 miles? I've heard all the talk about staying away from synthetics at this high mileage too, so what's the best non-synthetic? Thoughts?

-Brian

[ciper]

Fully synthetic 10w-30 Mobil 1. If you'd like, since you are local I will show you my car which is currently on about 4600 miles since last oil change and the oil level has dropped maybe 1/8 to 1/4 inch max.....

Btw I have almost 150k on the car and I drive it very hard, I used to autox and now I prefer rallyx.

Anyone who tells you not to use synth doesnt know what they are talking about.

You want to get together some time to chew the fat? I live near the SF Zoo and work in Fremont.

[Aaron's ej22t]

yeah, someone one here told me not to use synthetic cause my cause has 102.000miles. I was going to switch cause i know it is better oil, but he said all my gaskets and seals would start leaking oil if i did switch.

[eastbaysubaru]

I'm currently using Mobil 1 in my g/f's '00 RS. I also recently had the valve cover gaskets replaced, so I'm not too worried about those leaking, it's the head gasket I'm worried about. The other thing that I've noticed lately is that Mobil 1 has changed their formula. It seems there's only the "higher mileage" formula around now. I've heard that this new stuff is no longer fully synthetic which made me a little concerned. Any thoughts on the new Mobil 1? Is the old fully synthetic stuff still around?

-Brian

Ciper, we should get together sometime. I'm in Oakland and was at the first rallyX. We talked briefly and I even mentioned there was a "Ciper" on the i-Club. I was just driving my g/f's '00 RS at the time.

[ciper]

None of the synths are fully synthetic. Most of the time they have the 80%+ of the lab created molecules then 15%- of dino that also has all the additives.

I have seen both the high mileage and the new car formula around here. Usually the 10w-30 is high miles while the 15w-40 and others are new car.

I doubt your car would start leaking because of the oil, if it did you could always switch back but think of it as an indicator that the gaskets have already failed. Synth oil doesnt shorten the life or damage the gaskets.

I checked my oil and in 4700 miles using a tape measure it has dropped just under 1/4 inch (say 3/16?)

[Legacy777]

using the syn motor oil is pretty much ok on high mile cars.......I would not recommend switching back and forth. That is what is going to cause your leaks.

Syn oils use a different type of seal conditioner polymers & such. Switching back and forth is something I'd advise against.

Use one or the other, & stick with it. You should really stick with the same brand of oil as well.

Each oil manufact is goin to have different additives. Over time of using the same type of oil. The additives/oil molecules adhear to the metal surfaces. When you switch brands of oil. The different set of cleaners/additives come in there, strip down the old oil's extra barrier.....and has to build it's own back up again.

[ciper]

eastbaysubaru: I think I remember you, all the ciper's you see are me. Where are you at in the daytime during the week?

[eastbaysubaru]

I'm in Montclair up in the Oakland hills. That's where my office is. What about yourself?

-Brian

[ciper]

Usually Im not a mile away from the 880 and 84 interchange. I usually take 92 going home.

Id like to have you drive my car and give feedback, Im so used to it now I cant tell anymore. Depending on when we get together I may have different rear springs (15 pound increase, 1/2 inch drop) new rear strut tops and a new rear wheel bearing over what I had previously

[scoobiedoo22]

About the synthetics and causing seals to leak, I emailed an Amsoil tech to see what I could dig up if this was true or not.

This is what I wrote to them:


>Comments
>I have a 1990 Subaru Legacy 2.2L non-turbo, manual trans, 160,000 miles,
>that I am looking to swich from conventional oil to either your SAE 5W-30
>Full Synth or 10W-30 High Perf. Synth, along with using your Engine Flush
>before swithching oils. My concern is that I have heard on several accounts
>that higher mileage engines (mine having 160,000 miles) have had problems
>with seals and gaskets starting to leak after switching to a full synthetic
>because your products works so well at removing deposits that have built up
>around these seals, thus causing them to leak. Do you have any
>information/related data on the posibility of this happening (or not
>happening) in higher mileage engines. Thank you, john k



Their reply was:

>From: Tech@Amsoil.com
>To: "'scoobiedoo22@hotmail.com'" <scoobiedoo22@hotmail.com>
>Subject: RE: Technical Service Contact Form
>Date: Tue, 22 Oct 2002 09:47:02 -0500
>
>John,
>
>There is some truth to your concern about sludge and seals. The fact of
>the
>matter is that if your Subaru is not leaking now changing to a synthetic
>will more than likely not cause any leaks. I highly recommend our AMSOIL
>ATM 10W30 for this application.
>
>Thanks,
>Ed
>

[eastbaysubaru]

I'd also like to have you drive my car as well. Email me and we can get something figured out.

-Brian

[entirelyturbo]

Just to get my opinion in here, I use Valvoline 10W30 SynBlend in my car, not just engine oil but gear oil, too. I haven't noticed any changes in performance, but I looked at my valvetrain when changing valve cover gaskets and found everything to look like brand new after 113k. I'm not gonna fix it if it ain't broke!!!

[Aaron's ej22t]

well, my car has 103k on it. i just switched to castrol fully syntec 10w-30. i love it! the only leak i have is from my bosch oil filter. i recommend only using the oem. purolator oil filters. they fit & seal the best.

[kelley]

I will only use neo 10/30 fully synthetic oil. neo and redline are the only true synthetics. the idea is that it keeps the seals plyable so they don't become brittle. just my .02

[ciper]

I was wrong in one of my posts, some of the synth oils are fully synth. A few use a synthetic additive package. My bad.