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Rear diff & manual tran fluid change


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I'm wondering if there is anyone out there willing to give me the best directions on changing out differential fluid and manual transmission fluid on my '95 Legacy Outback? I honestly don't know of the last time either one of these has done, much less if they were even done by the previous owners.

 

Also- any ideas on the exact types and amounts of fluid I'll need?

 

 

Thanks!!!

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What the heck, I'll give it a try!

 

Before you start, figure out how you're going to add new gear oil. The front has to be refilled through dipstick tube--the rear diff through the top plug hole. (I made a rig with small plastic tubing siliconed to the snout of a small plastic bottle, cut off the bottom of the bottle and hang it up high so the fluid can slowly flow down.)

 

Drain the transaxle just like you change motor oil, just make sure it's the transaxle sump that you're draining!

 

Rear diff has two plugs, one over the other, that unscrew with a 1/2" drive (1/2" breaker bar fits perfectly.) Two warnings here:

 

1) Make sure you loosen the top plug first--to make sure you can add fresh oil after you drain the old out of the bottom hole!

 

2) The plugs are gonna' be tight! You'll probably need an extension pipe for leverage. If that doesn't work I've had good luck using the car's scissor jack to put pressure on the breaker bar (be very careful to apply the force perpendicular to the bar--if it slipped it would be very dangerous.)

 

My homemade filler tube worked well for the rear diff too--suspended the bottle by the rear wheel and snaked the tube through the wheel well to the top (fill) hole.

 

Fluids: A good quality gear oil--API GL-5 SAE 80W-90 front & rear.

(Although some of us swear by Red Line 75W-90ns for smooth shifting! Front end only, not in the rear diff.)

 

Quantities: 3.7 qts for the transaxle, 0.8 qts for the rear diff.

 

Good luck.

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What the heck, I'll give it a try!

 

Before you start, figure out how you're going to add new gear oil. The front has to be refilled through dipstick tube--the rear diff through the top plug hole. (I made a rig with small plastic tubing siliconed to the snout of a small plastic bottle, cut off the bottom of the bottle and hang it up high so the fluid can slowly flow down.)

 

Drain the transaxle just like you change motor oil, just make sure it's the transaxle sump that you're draining!

 

Rear diff has two plugs, one over the other, that unscrew with a 1/2" drive (1/2" breaker bar fits perfectly.) Two warnings here:

 

1) Make sure you loosen the top plug first--to make sure you can add fresh oil after you drain the old out of the bottom hole!

 

2) The plugs are gonna' be tight! You'll probably need an extension pipe for leverage. If that doesn't work I've had good luck using the car's scissor jack to put pressure on the breaker bar (be very careful to apply the force perpendicular to the bar--if it slipped it would be very dangerous.)

 

My homemade filler tube worked well for the rear diff too--suspended the bottle by the rear wheel and snaked the tube through the wheel well to the top (fill) hole.

 

Fluids: A good quality gear oil--API GL-5 SAE 80W-90 front & rear.

(Although some of us swear by Red Line 75W-90ns for smooth shifting! Front end only, not in the rear diff.)

 

Quantities: 3.7 qts for the transaxle, 0.8 qts for the rear diff.

 

Good luck.

 

Hey, that was perfect, thank you so much!

 

I've read a few things about Redline's fluid and most people seem to gravitate towards that... I'm actually quite conflicted about which fluid would be the best.

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Hey, that was perfect, thank you so much!

 

I've read a few things about Redline's fluid and most people seem to gravitate towards that... I'm actually quite conflicted about which fluid would be the best.

Check your owner's manual; I believe they specify 75W-90. I like the Redline (without the NS for lower mileage transmissions AND the rear diff). NS for high mileage transmissions; but stick with the non NS for the rear diff.
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Filling the rear diff is a bit tricky, because of the limited overhead clearance.

 

First, screw in the lower drain plug.

 

I use a 1 litre plastic bottle (1 US quart would work just as well). I use the type that has a tapered top, with a small nozzle in the cap (looks a bit like the top end of a caulking tube).

 

With this bottle full, or nearly full, of oil, I aim the 'nozzle' into the top filler plug-hole, and squeeze the bottle. I can only just about get the bottle to the horizontal, or slightly above horizontal.

After a few squeezes, I am blowing air; so the bottle needs to be refilled.

I keep filling the diff this way, until the oil starts to flow back out of the filler plug-hole.

 

That tells me that the oil level is correct. So then I screw in the top plug.

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