Determining rear diff health

[guitarguy]

While my 'Runner is up on blocks, is there a way to tell what condition the rear end is in? For example, "Turn this way and the other wheel does THIS, turn it the other way and it's supposed to do THAT", etc. And also guidelines for acceptable amounts of slop & play. Any help is appreciated!

It's a '74 with an 8-1/4, I don't think it's sure-grip because the car has very few options... but I don't know how to tell that up on blocks either.

Thanks everyone!

 

[mopar367]

The way I have checked open differentials was when the rear end is up in the air. I turned one wheel back and fourth to determine how much play is in the diff. And between the wheels. If there's any play it means your carrier pin is worn in the housing. I have had many of the 8 1/4 diffs and they all have had the sloppiness and it was the carrier pin.

 

[Meep-Meep]

About all you can do is check for slop in the gear train like 365 said. You can also remove the rear cover and have a peek inside for anything obvious, but if you don't know what you are looking for it might as well be Greek to you. With the rear end up on blocks and the trans not in park, turn one wheel and see if the other turns the same direction. If the trans is in park you shouldn't be able to move the wheel or have resistance while trying to do so.

 

[Supershafts]

If you aren't going to take the cover off and REALLY look and inspect, might as well find something more constructive to do then waste time playing guessing games.

 

[HEMI-ITIS]

Does it even have a rear cover??:confused4:

 

[Supershafts]

op says he's got a 8.25

 

[ply64post]

rear diff identify

Does it even have a rear cover??:confused4:

Hemi

Just as it says spotters guide.

 

[HEMI-ITIS]

See what happenz when I post without puttin me glasses on:icon_dwarf::laughing6:

 

[guitarguy]

If you aren't going to take the cover off and REALLY look and inspect, might as well find something more constructive to do then waste time playing guessing games.

Ok, how about this?

:toothy5:

Maybe you could tell me what to look for? I obviously don't know. Might be more constructive of you to share some knowledge with me since that's what I'm here for.

 

[Supershafts]

Take the cover off inspect the ring for any chips, cracked teeth and the same with the pinion, remove the driveshaft and check for any play at the pinion up/down, side to side, in and out (if you have any noise coming from the diff this may be one reason why) then inspect the spiders turning them completely looking for any chip or excessive wear, cracks, take the spider cross pin and see if you have excessive movement and can rock it in the carrier bore.
Using a dial indicator check the BL at the ring (factory set was .008) and see how much metal you have in the housing and oil, take a bar and use it to see if you have any movement (using the dial indicator against the side of the carrier or ring and at the top) up and down and side to side in the carrier.

 

[guitarguy]

Well thank you, Supershafts, I do appreciate that.

 

[HEMI-ITIS]

Well thank you, Supershafts, I do appreciate that.

You've been SUPERSHAFTED:blush: