Rear differential fluid

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ncktuley1
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Rear differential fluid

Post by ncktuley1 » Tue Apr 23, 2019 3:03 pm

Im trying to figure out the correct fluid I need for my transmission & differential. I keep getting conflicting results, but does my baja have a rear LSD in it?
It's a 2003 sport, 5 speed. I was gonna buy a gallon of redline lightweight shockproof, but do I need to add an LSD additive to the rear diff?

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anarchy1024
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Re: Rear differential fluid

Post by anarchy1024 » Tue Apr 23, 2019 3:08 pm

Everything I read online says, no, don't put in an LSD additive. Yes, you do have a rear LSD (from the factory, anyway), but it's a sealed unit. The gear oil isn't getting to the LSD-specific parts. You just use the same 75W90 oil that's used for the transmission.

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kamesama980
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Re: Rear differential fluid

Post by kamesama980 » Wed Apr 24, 2019 9:23 am

anarchy1024 wrote:
Tue Apr 23, 2019 3:08 pm
Everything I read online says, no, don't put in an LSD additive. Yes, you do have a rear LSD (from the factory, anyway), but it's a sealed unit. The gear oil isn't getting to the LSD-specific parts. You just use the same 75W90 oil that's used for the transmission.
This is correct. Even if you have a LSD, subaru uses a sealed viscous LSD. LSD additive is for clutch-type LSDs.
-Russell
"You don't get to judge me for how I fix what you break"
03 sport 5mt
05 turbo 5mt vf39 and other STI bits, 3" turbo-back

walfredo
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Re: Rear differential fluid

Post by walfredo » Fri May 03, 2019 8:01 am

+1 75W90

greymud
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Re: Rear differential fluid

Post by greymud » Sat May 04, 2019 9:18 am

This seems like a good place to ask a stupid question that's related.

I have an 050 MT with manual tranny. The tranny is also the front diff, correct? I'm planning on changing them out, just not sure I'm reading the manual right.
05 NA 5MT

HaHaBajAlcyone
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Re: Rear differential fluid

Post by HaHaBajAlcyone » Sat May 04, 2019 10:56 am

Yes, the front differential and the transmission share the fluid.

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