Differential oil level

[DeVilliers]

Hi all,

Happy new year to all of the TAC members.

How do I know if there's enough oil in the rear diff?
There's no filler hole in the cover plate, so can't use that. I've filled oil through the breather hole at the top, but how do I know if it's enough? I thought about some form of dipstick (a simple zip tie will do) and them perhaps try and measure so fluid is just over halfway.

Any better suggestions?

Regards,

[Wallington]

From memory it's just below the fill plug level, you can only poke finger tip half way in and when the fluid touches, close enough.

[DeVilliers]

From memory it's just below the fill plug level, you can only poke finger tip half way in and when the fluid touches, close enough.

Like I said, I don't have a fill plug in the cover plate.

[Wallington]

Not in the cover plate, in the side of the casting. Fill at the breather, at worst it will start to weep when it gets to the hole. Button it up.

Diff restored by Ben, on Flickr

[5th T/A]

I wish my differential looked that nice, almost too pretty to hide underneath the care. As Wallington said it should be just up to the plug on the side, assuming the diff is level when filling it. Not just side to side but also front to back as it would sit in the car on level ground.

[nUcLeArEnVoY]

Saved me from asking this question, haha.

Don't forget to add friction modifier additive to whatever gear oil you choose.

[DeVilliers]

Not in the cover plate, in the side of the casting. Fill at the breather, at worst it will start to weep when it gets to the hole. Button it up.

Diff restored by Ben, on Flickr

Completely forgot that plug is there 

Thanks

[DeVilliers]

Quick question.
What size is the plug "square"?

[Wallington]

I'm thinking 3/8 or 1/2 as per socket set, think that's all I used.

[DeVilliers]

I'm thinking 3/8 or 1/2 as per socket set, think that's all I used.

Both set's I have don't fit, hence the question. I'll have to mill something to fit. Guess it's measure, measure and measure some more.

Thanks

[sreta]

What about the clip between the vent plug and the oil plug, I guess another hard to find parts ?!

[Wallington]

That's not my diff photo above, but the brake line and spiraling has been redone and copies the transverse muffler type.

There's a second retainer bracket that comes off the helmet cover and offset brake hose bracket on the twin muffler versions.

Diff restoration complete 3_12 8 by Ben, on Flickr

Firebird diff brakeline retainer replated spare (2) by Ben, on Flickr

I've had 4 diffs, to come up with 2 of the clip, 1.5 of the offset bracket and 1 of the cover bracket. Not the sort of thing that gets pulled to sell online but anyone parting these things out will likely remove a few clips here and there if someone gives them a shopping list, like I did way back for trivial items.

Sorry, I can't recall the filler size, many years ago now.

[sreta]

Thanks Ben !

[sreta]

Btw, my rear end has a threaded hole on top, maybe someone know what is it for ?

[sreta]

It came from '76 Camaro, if matters.

[wheels78ta]

Does the hole go all the way through the case?

If not, it's probably for a clamp to hold the brake cable.

[Wallington]

My 2x 78 and 1x 79 model Firebird diffs didn't have the casting there at all.