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Discussion Starter · #1 ·
Lots of people mention the subject, but maybe it needs it's own thread.

Change your gear oil to synthetic as soon as you can. I used Mobil 1. One gentleman (he inspired me) used Redline. It might be better but its hard to find, here.

Keep the car level (no ramps, you can reach the drain) and drain every drop of the old oil. Mine only has a few K miles on it. Since my car is lowered, I needed my skinny son to get at the drain plug. Don't lose the washer!

You'll need a long a$$ funnel. Then dump in that Mobil 1.

I think the owners' manual is wrong in the capacity. It calls for 3.75 quarts. I used 4.

Then go for a drive and be prepared for a seriously dramatic change in your shifting and transmission behavior. It's hard to believe it's the same machine.

Go figure.

:) :)
 

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Russ,

Previously, I have used Amsoil in my transmission in my old Acura GSR. It was better in many ways, but I did notice that there didn't seem to be enough friction for the synchros to function properly. I found that a half and half mixture seemed to be right.

Do your synchros still function with full synthetic?

Bill
 

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Discussion Starter · #3 ·
Bill,

I only have a few miles on it since I changed the oil and haven't noticed a problem yet. I'll watch out for it though.

Russ
 

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lots of people use mobil 1 gear oil with no problems....but all the mechanics I talked to say wait till about 30K miles so the gears wear in properly.
 

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Discussion Starter · #5 ·
Just ran 180 mi. to a SCCA rally (the sooby won) over some of the greatest road I've ever driven. Rt 522 Nort from Rt 60 in VA. What a road. Lots and lots of shifting. No synchro problems. Skinny son an I loved it.:D :) :D
 

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gear oil

What about vibrations/noise when you down shift gears?
does anyone think that the fluid could be related to that?





Maury red wrx
10k
 

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HATE that "sounds like i'm in reverse" noise...reminds me of the sound the cars on the Jetsons made. bleah
 

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I'm sure this has been mentioned, but check out this article:

http://www.cobbtuning.com/tech/gearoil/index.html

I really like my Redline ShockProof Superlite - box and rear diff. We put Lightweight in my buddy's Impreza L yesterday. He says it's great but I haven't tried it yet. For him it fixed some synchro problems he was having.

edit: tried it. he's right. it's great.
 

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There are enough documented "grinding problems with synthetic" on i-club that I ended up putting regular gear oil back in the trans, while changing to Red Line synthetic for the rear diff.
 

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I was also wondering if synthetic oil of mobil 1 is as good as it used to be considering that they now use "hydrocracking" to produce a "synthetic" base from petrolium. They sued Castrol for doing in the same thing with their "synthetic" oil but Mobil lost the suit, and afterwards also adopted the practice which is MUCH cheaper than producing a true synthetic base (and since the price hasn't changed, they just pocket the difference). the old Mobil 1 was rated for jet engine use...the new one is not. From what I've read, it still a better base than regular oil, but it no longer provides NEARLY the performance it used to (like extended temperature resistence since its now back to being hydrocarbon based rather than graphite) and is really not worth it anymore...and if you change your oil every 3000 miles there is NO noticable difference in wear and performance.
 

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russ said:
I think the owners' manual is wrong in the capacity. It calls for 3.75 quarts. I used 4.
:) :)
Sorry I didn't get to this thread sooner, but BE CAREFUL:

Overfilling your tranny or differentials can cause serious problems like blown seals and such. The cases are not meant to be completely full.

An extra 1/4 quart shouldn't hurt anything, but I just wanted to make this point clear to everyone!

-Jim
 

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Discussion Starter · #15 ·
Jim,

After a day or two of running, I rechecked the level and it was 1/4 qt. high. I took the Mitey Vac and removed the excess.

Russ
 

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according to an article i read, its good for the diffs, it doesn't offer enough friction for quick shifts in the trans. (make if last for ever if you want to granny-shift though).
 

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I just put in redline MT-90 in my car. It is 3.7 qts btw.
It does make a big difference. My car would scratch going into 2nd gear, but that is gone now.
 
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