can anybody please confirm this a 8 3/4 rear differential and name a part?

[Michael_]

See pictures.
I think its a 8 3/4 rear axle/differential, right?

And how is the other pictured part called?
Would need that replaced including a new seal.

 

[Photon440]

You have outlined the universal joint, part of the driveshaft, the output yoke and the axle yoke dust shield. If you are only removing the universal joint, no seal is needed.

 

[beanhead]

Yes, that is the 8-3/4. Looks to be the '489' casting. Beefy.

 

[Fran Blacker]

If the last 3 numbers on driver's side are 742 I would contact drdiff for that pinion yoke seal.

 

[451Mopar]

I think you mean the pinon yoke and pinon seal?
https://www.doctordiff.com/8-3-4-pinion-seal.html

Mark the pinion nut location and number of threads showing above the nut (a picture helps too) before removing the yoke.
You should get this yoke holder and puller tool for this job:
https://www.summitracing.com/parts/...MIi97b0uux6gIVDtvACh2v5wOyEAQYCSABEgI7APD_BwE

You can remove the yoke with a different puller or carefully tapping the pinion off, and hold the pinion from turning with the emergency brake, but for $23, the tool is nice to use.

after replacing the seal, Re-install the yoke and tighten the nut to the original position you marked originally to keep the same pinion pre-load.

 

[Bad B-rad]

Be aware if its a 489 rear they use crush sleeves for bearing preload.
So use caution when replacing this seal and re torqueing the nut on the yoke.
ONLY on the 489 housing has crush sleeves.

 

[khryslerkid]

We need the last three numbers in the casted numbers on the driver's side Before anyone can give you advice.

 

[khryslerkid]

I think you mean the pinon yoke and pinon seal?
https://www.doctordiff.com/8-3-4-pinion-seal.html

Mark the pinion nut location and number of threads showing above the nut (a picture helps too) before removing the yoke.
You should get this yoke holder and puller tool for this job:
https://www.summitracing.com/parts/...MIi97b0uux6gIVDtvACh2v5wOyEAQYCSABEgI7APD_BwE

You can remove the yoke with a different puller or carefully tapping the pinion off, and hold the pinion from turning with the emergency brake, but for $23, the tool is nice to use.

after replacing the seal, Re-install the yoke and tighten the nut to the original position you marked originally to keep the same pinion pre-load.

Only if it's a 489

 

[dadsbee]

First picture you can see the 28314..

 

[451Mopar]

Only if it's a 489

What does that mean?

On the Dr Diff web suite, you can select either seal depending on the case number.

When re-installing the yoke, you want the same pinion pre-load. Crush sleeve or shims, you want to put the same pre-load back.

 

[DeltaV]

See pictures.
I think its a 8 3/4 rear axle/differential, right?

And how is the other pictured part called?
Would need that replaced including a new seal.

View attachment 970683 View attachment 970684 View attachment 970685 View attachment 970686

We are looking for a picture with the full casting number like this:

 

[Michael_]

Unfortunately i did not took a photo from that area and the shop is about 45min away.
I will let them know hopefully they can send me a picture or at least the number.

They told me the marked area in the first picture is one part + seal.
well seems like they have been wrong about that.

 

[Thrashingcows]

If the shop does not know what what those parts are I'd be taking it to another shop....

 

[Michael_]

If the shop does not know what what those parts are I'd be taking it to another shop....

They know what it is but i live in germany. They dont know what its called in english.
But yes they assumed its just 1 part + seal which is as i now know not the case.

They are also specialised in corvettes and mustangs. But i already let them perform work on my cutlass in the past. They do a good job.
But despite they doing this since the 80s he says its the first 69 charger he had in his shop. Seems they are more rare in germany than i thought.

Most people in germany buy corvettes and mustangs if they buy an american car at all.

 

[Bb70charger500]

What is the problem exactly yokes don't usually need to be replaced and it looks dry
Are they just wanting to replace the u-joint?

 

[Michael_]

They say it leaks. I guess they cleaned it up.
I want them to perform a full service including change of differential oil and seal.
So they want to make it properly.

 

[khryslerkid]

What does that mean?

On the Dr Diff web suite, you can select either seal depending on the case number.

When re-installing the yoke, you want the same pinion pre-load. Crush sleeve or shims, you want to put the same pre-load back.

Preload on the 489 is done with a crush sleeve. Over tightening it will change the pre load. You are correct to mark the nut.

741/742 preload is set with shims and the nut is torqued to 150 + ft lbs. (I know fms says 240 ft lbs but thats overkill or just incorrect) The shims won't let the backlash change unless you add or remove them. Just tighten the nut.

 

[DeltaV]

Overall comment, @Michael_ should get a Factory Service Manual and a Parts catalog. Originals, as well as reprints can be found on line. They might be available on digital media too.

 

[Michael_]

I already have that service manual. I lend it to the shop while the car is there.

 

[POMONAMISSEL]

could be the seal or the yokes leak sometimes as well . down the splines out through the washer nut combo .