please check backlash

[aznpoopy]

http://i10.photobucket.com/albums/a104/kirinpoopy/Image031.jpg

does this look right to you guys?

seems like what the fsm calls 'face contact'
but shit i've never done this before

[clark]

well what is the background?

did you swap the ring gear to a different differential unit? have you changed bearings?

did you pull out the pinion gear/shaft?

are you re-shimming?

you need many special tools and very precise measurements.

i tried to swap it myself as well, i got it shimmed perfectly but it turns out one of the bearings pitted to shit. i had to take it to a transmission shop.

you will honestly be better off taking it to a shop and having them do it the right way. you won't have some ghetto rigged differential.

i know it's not what you want to hear but it really pays off in the end.

but judging from the face contact, looks like your pinion shaft needs a spacer so it sits "deeper" in the ring gear

[aznpoopy]

its original ring gear / shims / etc all from an old open unit. pinion was untouched.

appreciate the input.

i think i will end up taking it to a shop to get it done.

[Def]

Looks a little toe heavy to me. Notice how the dye is much more prominent on the lower portion of the gear face, and almost gone all the way up to the top - that lets you know it's really putting pressure up top.

You ideally want an almost elliptical undyed area in the middle of the gear face, with dye on ALL sides of the contact area.

[Row]

Looks like the contact point is too high on the coast side.

[JRas]

that's tooth contact, backlash is different

[!Zar!]

Tooth contact IS backlash.

[Def]

Tooth contact IS backlash.

No - it's not, but it does influence it.

Pinion height also influences backlash even with the same tooth contact place.

[aznpoopy]

You ideally want an almost elliptical undyed area in the middle of the gear face, with dye on ALL sides of the contact area.

interesting. i had that pattern to start with then someone on the internet told me the actual contact patch should be shown by the dye (rather than absence of dye), which is what it says on the prussia blue bottle. so i redid it a few times to get the pattern you see above. i'll do it again tonight and post pics

hopefully it's alright. because i've called a couple transmission shops and while they do differentials, they refuse to touch it as soon as they hear the diff is out of the car and i just need it set. :confused:

[Def]

Well, are you putting dye on the ring gear or pinion gear? Putting it on the ring gear then rotating it will tend to press the dye out of contact areas(not completely, but those dark edges are the boundary of engagement).

It should be very obvious WHERE it is contact regardless of the dye/no dye thing.

To me, it definitely looks like the greatest pressure is up at the tip of the ring gear which is bad.

[aznpoopy]

going on the ring gear. as for dye / no dye that's what i thought as well, but honestly i'm a noob at this.

i went ahead and did it the other way. didn't come out as clear as i'd like but i think it's obvious shit isn't right.

coast
http://i10.photobucket.com/albums/a104/kirinpoopy/Image033.jpg
drive
http://i10.photobucket.com/albums/a104/kirinpoopy/Image034.jpg

[JRas]

Tooth contact IS backlash.

tooth contact is hows the gear mesh together when they touch each other, while backlash is the slop or play between the gears.

to the OP this may help:
http://img397.imageshack.us/img397/9203/92742644vy7.jpg

[Def]

Looks like you might need to adjust pinion height, but it might be due to side shims.


Are those the stock shims? What diff is that?

[Jtuned_andy]

Like someone mentioned earlier, you should take it to a shop and have them do all this for you. If you don't know anything about gear mesh, proper contact patches and backlash settings your diff WILL NOT LAST.

You need to put pressure on the differential with a pry bar and spin it about 4 times forward and backward to get good paint transfer on the teeth

[aznpoopy]

it's an open diff with whatever shims came in it.

i'd love to take it to a shop and probably will, as soon as i can find one that will actually take it.

if it comes down to it, i'll just buy all the tools and a set of shims from courtesy and do it step by step from the FSM.

[S14DB]

What kind of marking compound / grease is that? ICCS...

[aznpoopy]

permatex prussian blue