Jump to content

Welcome to Ultimate Subaru Message Board, my lurker friend!

Welcome to Ultimate Subaru Message Board, an unparalleled Subaru community full of the greatest Subaru gurus and modders on the planet! We offer technical information and discussion about all things Subaru, the best and most popular all wheel drive vehicles ever created.

We offer all this information for free to everyone, even lurkers like you! All we ask in return is that you sign up and give back some of what you get out - without our awesome registered users none of this would be possible! Plus, you get way more great stuff as a member! Lurk to lose, participate to WIN*!
  • Say hello and join the conversation
  • Subscribe to topics and forums to get automatic updates
  • Get your own profile and make new friends
  • Classifieds with all sorts of Subaru goodies
  • Photo hosting in our gallery
  • Meet other cool people with cool cars
Seriously, what are you waiting for? Make your life more fulfilling and join today! You and your Subaru won't regret it, we guarantee** it.

* The joy of participation and being generally awesome constitutes winning
** Not an actual guarantee, but seriously, you probably won't regret it!

Serving the Subaru Community since May 18th, 1998!

Guest Message by DevFuse

- - - - -

Recommended Sealant for Diff Plugs??

  • Please log in to reply
9 replies to this topic

#1 Chip Hedrick

Chip Hedrick

    USMB Regular

  • Members
  • PipPipPip
  • 87 posts
  • New Gloucester

Posted 14 May 2004 - 11:58 AM

The rear diff cover on my '98 OBW is covered with oil. I intent to check the diff oil level this weekend (and probably just go ahead and change the fluid again). No, I do not hear any screeching noises coming from the rear diff, so there must still be oil in it.

I changed the diff oil last year. I did not put any sealant on the diff plugs. I wonder if that caused some of the diff oil to leak out.

Is sealant recommended? If so, can anyone recommend a type or brand?

Does anyone else have this problem? Could the diff oil be coming out of a vent hole somewhere on the top of the diff? I don't think that the gasket behind the diff cover is the reason, but I'll give it a closer look this weekend.

#2 Strakes


    Kaboom? Kaboom?

  • Members
  • 520 posts
  • Knoxville

Posted 14 May 2004 - 12:13 PM

I had a similar problem and it turned out that I hadn't tightened the plug enough. I tightened it a little more and the leak stopped. Maybe someone here knows what torque it should be tightened to...now that I own a torque wrench.

#3 archemitis


    guy smiley

  • Members
  • 3,554 posts
  • the big minnie

Posted 14 May 2004 - 12:35 PM

i think its a tapered pipe thread, so being loose would make it leak. they gotta be very tight. but teflon tape, or pipe dope (sealant white stuff) should work great.

#4 Chip Hedrick

Chip Hedrick

    USMB Regular

  • Members
  • PipPipPip
  • 87 posts
  • New Gloucester

Posted 14 May 2004 - 04:28 PM

Earlier this year I changed the diff fluid on my wife's '03 H6 Sedan, and I noticed that the factory had used some sort of black sealant around the diff plugs. There was still some on the plugs when I reinstalled them. The rear diff on her car is not leaking.

Does anyone know what that black compound on the diff plugs is? It has to be some sort of sealant.

#5 theotherskip


    Eat, Live, Breath Subaru

  • Members
  • 329 posts
  • Philly, PA

Posted 14 May 2004 - 04:47 PM

i think the air vent tends to get clogged and then leak. mine has been doing the same for about 10k miles. but i've cracked the fill plug and checked it every couple thousand or so and haven't seen a noticable drop. a little bit of oil leaking can make a really big mess...

as for the recommended sealant, here is what subaru recommends for a bunch of different applications. i used some permatex 599 the first time (ultra gray), and haven't used any on the recent times i have checked it. i think if it is tight enough, it doesn't leak at all. torque spec for a 97 is 32 ft-lbs.

Posted Image

#6 Chip Hedrick

Chip Hedrick

    USMB Regular

  • Members
  • PipPipPip
  • 87 posts
  • New Gloucester

Posted 14 May 2004 - 07:24 PM

The Other Skip: Thanks for your post. That's the info I was looking for.

#7 Strakes


    Kaboom? Kaboom?

  • Members
  • 520 posts
  • Knoxville

Posted 15 May 2004 - 12:19 PM

To theotherskip: Thank you!!!

#8 blitz



  • Banned
  • 1,091 posts
  • Warren, Michigan

Posted 15 May 2004 - 03:57 PM

I had the same experience as Strakes. Very wet rear diff which was cured by another quarter turn in on the drain plug.

#9 99obw


    this space for rent

  • Members
  • 1,595 posts
  • Ithaca area

Posted 15 May 2004 - 05:02 PM

I would be very carerful using sealant on those plugs, you don't want to contaminate the gear lube.

I have never had a leak, I just torque it to spec and coat the outside with never sieze.

#10 Crashton


    USMB Regular

  • Members
  • PipPipPip
  • 55 posts
  • Ohio

Posted 15 May 2004 - 07:29 PM

I used Permatex thead sealer with teflon. It's a thick paste that won't creap past the threads into the diff oil.

A little bit goes a long way.:)

0 user(s) are reading this topic

0 members, 0 guests, 0 anonymous users