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95 Impreza L AWD
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I was wondering if you are supposed to clean the diff's out with anything when changing fluids? I know they have the magnetic drain plugs but I was wondering if anything else is necessary? Also, what is the best value on higher-end stuff and what is the best regardless of price. Finally, can somebody tell me what differences I could expect if I switched to a synthetic? Thanks. :)
 
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I switched to Mobil 1 in the tranny and rear diff. The shifts seem a little faster or something. I don't know how to explain it exactly, but it's like everything seems to slide better, like there's a liquid in there instead of a soft paste. I was grinding the synchros on the 2-1 upshift when rolling about 2-5mph, but tonight I installed the STi tranny mount and it seems to have cured that problem. Other than that... maybe slightly better fuel economy.
 

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95 Impreza L AWD
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Discussion Starter #3
Do the tranny and diffs take the same type of fluid? I'm too lazy to run and check the manual. Also, did you use anything to clean out the differential or did you just drain it and refill it?
 

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Yep, 75W-90 for both. I didn't flush either out when I changed fluids, and I don't think there would be anything to allow to do that, but I could be wrong.
Make sure to do allot of research when picking a tranny fluid. I bought NEO 75W-90HD, and now it seems like my 1st gear syncro doesn't spin for sh*t.:curse: I think I'll try redline next, I've heard that it works well in our cars. But then again, NEO was supposed to be the best, so who knows...
 
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Loomis - my first gear syncro gave me crap too, but driving it around last night after installing the STi tranny mount it seems to be behaving itself much better!

And the only way I could see being able to flush the diff out would be to squirt oil in there under compression and let it drain out. Sounds messy to me, and not worth the hassle. Ooh. And expensive, since you wouldn't really want to use dirty oil again. ~$7/quart for Mobil 1, I assume more for Redline, Neo, Amsoil, etc.

I liked being able to pick it up at any auto parts store in the country, so I got the Mobil 1.
 
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Um. What year car do you have? I know the '01 RS uses the same fluid in both transaxle and rear diff, but I think they might be different in the older ones.
 

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95 Impreza L AWD
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Discussion Starter #7
I have a '95 L AWD with the :curse: 1.8. I probably should get my lazy ass up and check the manual!
 

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horatio - Where'd you get the mount, and for how much? Did you install it yourself, was it a PITA? Thanks
 
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I got the motor and tranny mount from Cobb, because I enjoy their service.

tranny only = 69.95
full set = 169ish

But Challenger Deep is a little cheaper @ 69/159
http://www.challengerdeep.com/

It was a PITA to install, but only because I managed to catch the edge of the front crossmember on my floor jack when I was raising the tranny up. :rolleyes:
It's a bunch of 12mm and two 17mm nuts to loosen. I loosened the exhaust at the manifold, then the point where it meets the tranny, then the two crossmembers. four bolts and two nuts and the stock one pops out. It's amazing how squishy the stock one is... and the new one isn't any louder really.. not as bad as I thought it would be.
 
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Loomis - Unfortunately tonight I found the first gear grindies again. Hmm. I'm just going to have to adjust my driving so that I don't go for first until I'm stopped. Next time I change the tranny fluid I'll try a different brand.
 

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horatio102 said:
Loomis - Unfortunately tonight I found the first gear grindies again. Hmm. I'm just going to have to adjust my driving so that I don't go for first until I'm stopped. Next time I change the tranny fluid I'll try a different brand.
Damn, sorry to hear that. I'll probably get the mounts anyways. I take it that the shifter doesn't wobble around anymore right? Like under hard acceleration.

Kickin_81: I put MT-90 in my last car, and I think it prematurely wore something out because I was getting all kinds of odd noises, and I later discovered that a few other people had the same problem. So it totally figures that MT-90 would work well with my scooby:rolleyes:. Cobb has way more experience than me, so I'll probably go MT-90 next time. At least I don't need to mail order it...
 

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05 Saabaru, 01 Legacy wagon
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Actually just finished the second half of my tranny/diff fluid change, diff last week, tranny today.

I used Redline 75w-90 in the diff (orange stuff) and put Amsoil 75w-90 in the tranny (cool blue color). Along with the normal golden-brown color of the oil I think I now have as many colors of fluids IN my car as Eric has ON his car... :biggest:

Took the car out to break it in, and already feel a difference. The tranny is a little smoother while under normal moving, and the shifting (both up and down) is nice and smooth. Ground third once, but I think I messed up clutching.

I'll know by this upcoming weekend how well it holds up for my daily driving (I do over 500 miles a week), but first indications are that it feels great and will doo a world of good for the car.

-Gary
 

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95 Impreza L AWD
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Discussion Starter #15
How much did you pay for the fluids? I want to change mine when it gets warmer but I don't know how much to expect to pay. I was thinking of Mobil 1 for the diff, but I keep hearing about Redline and Amsoil. Also, why didn't you just use the same fluid all around since they are the same weight? Thanks.
 
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Depending on what you buy, and how good of a deal you get, expect to pay $5-10/quart.
IIRC, the mobil 1 was like $7/q, and you need 5 quarts. (3.7 for front, 1 for rear - but that's just from memory)

So be prepared for $50 or so.
 

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I_H8_1.8 said:
How much did you pay for the fluids? I want to change mine when it gets warmer but I don't know how much to expect to pay. I was thinking of Mobil 1 for the diff, but I keep hearing about Redline and Amsoil. Also, why didn't you just use the same fluid all around since they are the same weight? Thanks.
Well, I didn't pay anything for the fluids, so I can't tell you exact. Friend of mine bought a couple cases through a group buy in the Supra club he belongs to. He said it averaged about $4/quart, and I got it free (he owed me a favor anyways).

He only had 2 quarts of the Redline fluid left, and almost a whole case of Amsoil, so that's why I used 2 different kinds. I had also been reading around where some poeple didn't like the 'normal' Redline fluid in the tranny - the shockproof stuff gets great reviews, but not the regular 75w-90. I was going to wait and order a bunch of the shockproof specifically for the tranny, but I figured if the Supra guys are running the Amsoil stuff, it's gotta be decent enough... their tranny's alone are about half of what I paid for my car :eek: !

So, since I've had a morning's commute under my belt, I still think the car is doing better. I have a little trouble when cold getting the car from 2nd to 1st, but no grinding, just patience works fine.

Hope this helps, any other questions, just lemme know.

-Gary
 

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MY00 Impreza 2.5RS, Aspen Whit
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Well I was going to change my Rear diff fluid today to the Mobil1, but I could not get the plug (bolt) off. Anyone got any ideas to make it easier to unscrew. I tryed so freakin hard but I couldn't budge it. I have never changed it before and I have about 60000 miles on my car so I would say its long overdue. Its called really being lazy. :happynow:
 
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