legacycentral bbs

Sorry if this has been covered before but my search didn't get me anywhere but to a ton of matching threads with little relavence. I just wondering what everyone's opinions are on synthetic vs. conventional oils is? I used to run Havoline Max Life 10W-40 in my old Colt Vista but I am currently running Valvoline Durablend 10W-40 in my Legacy. Opinions?

Lee

Synthetic on an old engine is bbbaaaadddd.

With a dino oil, a layer of varnish builds up over the low-flow areas around gaskets and such. This isn't really bad, but it's not good. This varnish seals the gasket, but also prevents it from getting fresh oil. So with the lack of good oil, the gasket cracks and dries out. But the varnish prevents it from leaking.

When you switch to synthetic, the varnish is cleaned out (thanks to those lovely cleaners in there). The varnish is cleared out, and the dry cracked gaskets are exposed for oil to leak from.

A gasket swap and synthetic is just fine to run in an old engine.

I stick with Castrol GTX 10W-30, dino oil.

I believe Phil's right as the engine was clean until maybe 20k after I switched. I've replaced a few seals, but it still leaks elsewhere.

Steve

Well it sounds like when I do my oil change in a few days I should be switching back to a dino. You don't suppose I've done any harm running a synthetic (been doing so for about 12k)? Oh, and any opinions or experiences on which dino to go with? Thanks guys.

Lee

if you've been using it for 12k and havent had any leaks or been burning anything I don't think I'd switch back, but then again I've never used synthetic...

I've switched to synthetic twice in two ej22s w/ 100k+ miles. The first had leaky seals before i switched and the second hasn't had any problems. I say switch if you want to and if the seals do leak just replace them, they're cheap and not hard to replace.

MK

If you read my burning oil thread here, you'll see that I was actually burning oil, and a lot of it, using the identical partial synthetic oil you are using Lee, Valvoline DuraBlend 10W40. I have now concluded that oil was not actually making it directly into the cylinders, but instead seeping through the exhaust manifold gaskets and burning in there, sending blue smoke out the tailpipe. The evidence is that there were zero oil deposits on my spark plugs...

The synthetic oil was leaking so bad from my cam seals that it was dripping down onto the manifolds. I switched to full Valvoline 10W40 dino oil and have not seen one single puff of blue smoke since, and I leak oil a lot less.

If you were to do as Phil suggested, completely reseal the engine and run synthetic, you would indeed benefit from having less friction in the bottom end and valvetrain, and would not have to worry about leaking/burning oil.

The previous owner of my car ran Castrol Syntec and I continued... it hasn't leaked or burned a discernable drop in the 18 months I have had it.

I have seen your thread subyluvr and was one of the reasons why I asked about oils. I leak a fair bit of oil (drips down onto the top of the exhast and after I park I can see the oil burning off) and thought that it was my synthetic. I'll definately make the switch to dino now. I'd prefere to reseal the engine but don't have the time or money to do such. Out of curiosity, how much difference do people notice between dino vs synthetic?

Lee

I was using Mobil's semi-synthetic for around 10k miles and most of my leaks seemed worse then they were with dino. I was going to work my way into Mobil 1 full synthetic. My plan was to use the semi-synthetic for around 15k then switch full synth. but I ended up switching back to Mobil's 10-30 dino oil after fixing my valve cover gaskets and I'm much happier with it. I had some other small leaks that seem to have cleared up.

What Phil said about the cleaning agents in the oil is true, however, that is only brand to brand. If you are using Mobil dino and switch to Mobil 1 synthetic, it should have the same detergents. Because of this I try not to ever switch brands of oil. Just my .02

If you drive a car hard or have big leaks already I would recommend the synth. Otherwise, save your money. I do believe the synth to be worth it in the circumstances I mentioned. My 1983 Sedan leaked horribly and may've burned a little (although I never saw blue smoke) using 15W-50 Mobil1 (I had tried the 0W, but whoa did that piss through!) and I drove over 3 hrs. to go camping and it was low when I left. Could not find anything but 2-stroke oil in the middle-of-nowhere Vermont, so the car had to deal with it. On the way back a Jeep Grand Cherokee started some shit with my ex who was driving her car so I pulled some some very angry shit on him that I like to think of myself as mellow enough now not to do. Anyway, with duelling with him for about forty minutes with the speedometer at 'P' (as in MPH) on the 85 mph speedo and the rest of the weekend driving I used a lot of oil. When I got back there was less than a quart in the crank case. Drove the car without any issues for another year (~25k miles) before a tree fell on it and I had to get my Legacy.

Steve

subyluvr2212 wrote:If you read my burning oil thread.....

Did you see blue smoke out the back when you gunned the accelerator when standing still?

If so, you were burning it....either way.....I don't think the exhaust manifold is hot enough to burn oil to create the smoke you saw.

The smoke I see is coming from the engine compartment and when the hood is up you can look down and see smoke coming from underneath the engine. It's been worse than it used to when I ran dino, I think, it's been a little while. Any how I'm putting in Valvoline Max life 10W-40 today while doing a general tune up.

BTW, I loved the story Steve and sorry about the tree.

Lee

Legacy777 wrote:

subyluvr2212 wrote:If you read my burning oil thread.....

Did you see blue smoke out the back when you gunned the accelerator when standing still?

If so, you were burning it....either way.....I don't think the exhaust manifold is hot enough to burn oil to create the smoke you saw.

I never saw any while I was driving, but I had a friend drive the car away from me and told him to get on it, in between the 1-2 shift, I saw a little puff pop out. No other time though.

Now I would think if oil can burn on the outside of the exhaust, it should have no problem burning inside contacting 1000-deg exhaust fumes... My plugs looked perfectly normal anyway, not one sign of oil deposits.

When I bought my Legacy in '98 it had organic oil in it (assuming that it'd always had organic). I think I changed my oil using organic only a few times after that until my friends dad sold me on Amsoil full Synthetic.

I've been using Amsoil Synthetic for as long as I can remember now and I've been very impressed. I would switch to 5W sometimes but then I read that 5W can be bad in summer and/or hard driving. I'm back to 10W now.

I tried out Mobil Synthetic once (it was a little cheaper) and within 6 months switched back to Amsoil after I really felt that my car was not running as well. I was not happy with Mobil's sythetic, I dont think it does as well as Amsoil's. Plus, Amsoil's synthetic goes for a full year (6 month filter change) before you need to change the oil. If you dont have to change for a year, you end up coming out on top anyway. I'm paying $5.85 a quart for it. I also attribute some of my fuel efficiency to Amsoils synthetic. I'm getting 28 city.

Matt - Dino oil almost always has less detergents than synthetic, even from the same company. Synthetic is lab-bred and has all of the detergents engineered into the mix. Dino oil has those detergents added in. Initially, when the oil is new, they have the same detergents. But over time, thermal breakdown occurs, and any detergents in the dino oil will be gone, while the synthetic will be good.

All of that aside, either go for the gold and use Mobil 1 Full Synthetic (arguably the best oil on the market) and replace your seals once they leak. OR, use Castrol GTX or Mobil 1 Full-Dino oil. I've always used Castrol GTX (if you care what I use).

Dont use Pennzoil. That stuff is horrible. ESPICALLY the "high mileage" stuff. That stuff is "designed" to keep the seals lubed and free of varnish (not a synthetic or blend, but it's a full dino oil). It "reconditions" the seals by essentially gumming them up. Not like a varnish, but like a sticky gummy substance. I remember my neighbor telling be about pictures he saw comparing Mobil 1 to Pennzoil in his Autotech class. The Pennzoil engine was all nasty. The Mobil 1 looked just fine.

Despite my hatred for Mobil, I use Mobil 1 as it's a product that I swear saved my last car's engine.

Notice the commercials for the Pennzoil high mileage shows cars with a whole 70k! Oo, wow. I don't even buy cars until they've hit 100k+.

Steve

Wow, I'm definately learning a lot about engine oils, keep the info flowing. You all mention the Penzoil high milage, what about the Valvoline max life?

hehe, I sell that penzoil higher mileage daily

I don't know much about valvoline. It's probably good stuff. Valvoline makes some other good products, so I don't see why their oil wouldn't meet the same standards. I'd still recomend Castrol GTX High Mileage.

Hardy, are you a part of the J-Team?

I've been using Mobil 1 for about 4,000 miles, and i've had very little problems from it, and the car has 188k miles on it. When I start having problems, I will probally replace the seals, and whatever else is causing the problems, and they don't go away, I will switch over to probally some dino 10w-40...

BAC5.2 wrote:Hardy, are you a part of the J-Team?

better believe it. Though I really want to start working for solberg's team

What's down in the pit? Anything exciting? I've always wanted to go down there.

tools, oil filters, fuel filters, rags, gear oil guns, a filter crusher, some lights, a trash can and a rag can that's about it

Sounds like it could be a fun torture chamber if you just added some big rings to the wall to attach chains.