Is anyone running synthetic fluids in their subies?

[busdriver]

Now I've never had a subie worth putting synthetic fluids into, they've all been on the junker side of things, but now that I have a decent subie, I'm going to give it the royal treatment and go completely syn. I have been running Valvoline Syn power 10w-30 in my VW GTI for almost three years now, and realize how much my Vdub appreciates it. It's nice knowing your oil is going the extra mile for you with seal swell agents, and sticky molecules to keep everything buttery smooth. Did I mention the horsepower increase? My butt dyno noticed a serge in power after going synth...me likey!

 

My second choice for a high quality lube is the Mobil 1 synthetic 10w-30. It's not as slippery as the valvoline, but in comparison to regular oils, Mobil 1 blows their doors off.

 

So just wondering if anyone else is running synth, and if so...what kind?

Also, what weight oil/ lube goes into the tranny. I believe it was 80, but I do not remember. Thanks and any help or replies.

[subiemech85]

could you be more specific as to which trans you have?

 

if it's a justy, run the thinnest you can find

 

I have synthetic turn signal fluid, now it sounds good! :cool:

[subyrally]

look into getting amsoil, its what i use when i can afford it, that and they have a huge change interval selection. they have motor oils that range from 7500 to 25000 miles between changes.not that i would go that long tough, i try to do mine every 5000miles. its some good stuff,

[Snowman]

Engine: Mobil 1 synthetic 10w-30

 

Gears: Quaker State synthetic 75w-90

 

 

I still testify that Mobil 1 is the only thing that kept one of my engines alive. Last year I had #1 lose all its rings. 75 psi compared to 150 in the others. I had to run it another 6000 miles, and it didn't complain one bit. It burned a quart every 400 miles or so. I'm positive that if I were running dino oil, it would have been much much worse and likely wouldn't have made it that long. I think it would have burned off faster, possibly running out of oil, and the reduced thermal stability of the dino oil wounldn't have been good for an engine like that.

 

 

Just be very careful with switching to synthetics in an older engine. If it's got more than 20 or 30k after a rebuild, reseal, etc. it's most likely going to start leaking.

[subyrally]

as a testament to amsoil, well, synthetic oil in general(possibly) my old boss's wire hit a rock in her mercedese and ripped the opil pan open, then drove from her home to the garage with no oil in the engine, about 25 miles. they always used amsoil in the car, there was no damage to the engine when they got it fixed. i wouldnt reccomend going out and trying to proove or disproove this though, some engines are different tthan others

[rallyruss]

I have run red line products in my cars with good results.

 

the trany fluid MTL (manual trans. lube) is by far some of the best out there. helps the synchros work smoothly for really nice shifts.

 

I was using the red line engine oil too but it is rather expensive and I went back to good old castrol recently.

[subiemech85]

reminds me of the slick 50 commercials!

[busdriver]

could you be more specific as to which trans you have?

 

if it's a justy, run the thinnest you can find

 

I have synthetic turn signal fluid, now it sounds good! :cool:

I'm rockin the GL10 5 spd tranny. I wonder where I can get some of that turn signal fluid, my blinkers are getting sticky

[rallyruss]

 

Just be very careful with switching to synthetics in an older engine. If it's got more than 20 or 30k after a rebuild, reseal, etc. it's most likely going to start leaking.

I dont know. I think this is an urban shade tree mechanic myth. I have never seen any proof of synthetic oil causing the engine to leak. I have used synthetic in motors with well over 100k on them that did not leak before or after synthetic. I have also seen plenty of low mile motors run on regular oil leaking. now is the oil to blame? or is it just a crappy seal job?

[DeathHatch]

i run a 15w-40 half synthetic and it runs great

[carfreak85]

We're running Mobil 1 10W30 synthetic motor oil in my old man's Rex. I might run it in my wagon after everything gets rebuilt. I don't see the need in my non-LSD rear end, non-RX tranny, and my engine with only rebuilt heads.

[Snowman]

Rallyruss:

 

Although the whole synthetic=leaks is often considered a myth, there is some substantiation. I've had many discussions with my automotive and diesel professors on the subject, and they agree. Here's why: In dino oil, the molecules are all different lengths. The larger molecules plug up the tiny gaps that develop around seals, gaskets, etc over time. The increased detergent properties of synthetics clean out these large molecules, and since the synthetic oil molecules are all the same size, there are no large ones to fill those gaps again, and you get leaks.

[Adam N.D.J.]

Royal Purple, this stuff is awsome, makes Mobil 1 look like Pennzoil. There are a good number of the race car guys here that run it, and have dyno graphs to show, my buddy got 4hp increase swithing from regular to Mobil 1 then he got 12hp increase switching up Royal Purple, so a total of 16hp from the engine oil. Then there is the tranny and diff fluid, he gained another 20Hp to the wheels by changing out the gear lube in the running gear. I run it in the turbo and in the Brat, and HP increase is way noticable, that, and it's PURPLE!!!

[Snowman]

Isn't that stuff really expensive?

[edrach]

My Legacy had 98K on the engine when I got it. I was using Castrol GTX 10W-30 and changing it every 2000 miles; I got tired of changing oil every two to three weeks so I switched to Amsoil 10W-30 at 120K which I change every 6000 miles. I didn't notice any change in the car, but I only need to add a quart of oil between 6K changes (as opposed to adding 1 quart every 2K between changes). I use Redline 75W-90NS in the gearbox.

 

My 1980 camper (Toyota 20R engine) is hauling around a slidein camper and I went to the Amsoil also. I only put 3000 miles on the car every summer so I only change the oil every spring. The engine runs slightly cooler and I've noticed a slight sheen of oil on the outside of the engine since I started using it. I don't lose any oil between changes anymore.

 

My Brat's new engine only has 3000 miles on it and I'm still running the Castrol; when I get to 10K or so I'll switch to the Amsoil. The tranny also has the Redline 75W-90NS. I used Kendall's LSD diff oil in the rear.

[rallyruss]

Rallyruss:

 

Although the whole synthetic=leaks is often considered a myth, there is some substantiation. I've had many discussions with my automotive and diesel professors on the subject, and they agree. Here's why: In dino oil, the molecules are all different lengths. The larger molecules plug up the tiny gaps that develop around seals, gaskets, etc over time. The increased detergent properties of synthetics clean out these large molecules, and since the synthetic oil molecules are all the same size, there are no large ones to fill those gaps again, and you get leaks.

ok I will bite. the supperior detergent packages in synthetic oil is the best part about them or and standard oil with a good detergent package.

now you mention larger molecules in gaps. that sounds like poor sealing to me. there should be no "gaps" in a properly sealed motor. trust me I have done both good sealing jobs and bad ones. and on the bad job any kind of fluid would have leaked out.

so ok lets say this is true. then if you have a motor with some amount of "normal seapage" and you really dont want to mess with resealing it you may see some increase in the leakage if you swith to synthetic. I would buy that scenario.

ok point taken.

 

as for the expense of the stuff? if you find cheap synthetic oil its probably just that "cheap"

I personally dont run with the Royal purple crowd. I used to sell it. there were some fishy aspects to it. I dont really trust them. its a red line knock off in my opinion.

I have heard lots of testamonials about Amsoil from people who swear by it. hey that must mean somthing.

I chose Red line because they are a local company (to me) and have been verry helpfull in the past when tring to find a special oil or specifications on the products. they also are used alot in racing.

[subiemech85]

so then, any difference with royal purple purple ice and redline water wetter?

[dptyrob]

I use synthetic in everything I own. I've got an old 83 Crown Vic with a 302 from an 84 Grand Marquis. That engine had 130k miles on it when I dropped it in over 6 years ago and she's now well over 200k. It's still running great and I probably don't add more than 1-1 1/2 quarts of oil over the 5k miles between changes. With the extended change intervals with the synthetic the expense of using syn should have you at least breaking even with dino oil.

[84Scoobaroo]

I know it may be Pennzoil, but its synthetic and its free, change it every 3k, got me home with no coolant, and no damage to the bearings. Did cause a few leaks, mostly due to the fact that my valve cover gaskets were gunked up with old dino oil. Fixed those and no leaks until it Blew a HG, BAD when boost spiked. Now water pours out the tailpipe. Yay.

[bratman2]

Switched the Brat to Mobile 1 at 143k now has 191k with a change every year, that's 8k per change and add about 8 ozs. at 4k. Also have Redline in the transmission, it took care of a minor gear scrapping issue that I couldn't resolve. Legacy 93, switched to Mobile 1 at 115k currentily has 175k and change it every 10k adding about 8-12ozs at 5 k, no problems with either Sub and no leaks.

[subaru_styles]

Mobile 1 in the engine, Redline in the tranny

[busdriver]

Engine: Mobil 1 synthetic 10w-30

 

Gears: Quaker State synthetic 75w-90

 

 

I still testify that Mobil 1 is the only thing that kept one of my engines alive. Last year I had #1 lose all its rings. 75 psi compared to 150 in the others. I had to run it another 6000 miles, and it didn't complain one bit. It burned a quart every 400 miles or so. I'm positive that if I were running dino oil, it would have been much much worse and likely wouldn't have made it that long. I think it would have burned off faster, possibly running out of oil, and the reduced thermal stability of the dino oil wounldn't have been good for an engine like that.

 

 

Just be very careful with switching to synthetics in an older engine. If it's got more than 20 or 30k after a rebuild, reseal, etc. it's most likely going to start leaking.

actually, That is not correct. Any decent quality synth will have seal swell additives that will out perform normal oils. It's suggested to use a synth. after your engine has clocked 75k miles. since after that point the wear on your engine is increasingly multiplying. The seal swell will actually absorb into the seals and inflate them to their original size and increase elasticity making the seals more pliable. just like having the sticky molecules to help protect against wear when your low or out of oil, synth. oil just plain rocks the house no matter how you look at it.

[Snowman]

Hmmm...... I'll have to ask about that. That does make sense.