Scored a 8 3/4 help please

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DartThis74

DartThis74

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And now I need some help from y'all. This rear end obviously need to be fixed up with new bearings and gaskets, but I don't want to spend $200+ for the local shop to work on it. Where about on the internet or local auto supplies stores would I be able to get the axle bearings, gaskets, seals and things needed to rebuild this rear end to get my Duster on the road. This is an 8 3/4 741 housing out of a '66 Charger, and never done this before, could anyone try to attempt at directing me toward some simple procedure in rebuilding it. Any websites that can tell/show me how to go through one of these? Thank you for any help I appreciate it !!
 
Talk to Dr. Diff for bearing and seals http://www.doctordiff.com/ but a word of caution, if you're planning on replacing the carrier and pinion gear bearings and haven't done this before I would seriously recommend letting a reputable shop handle the task. When it comes to setting the ring gear and pinion gear tooth contact it's really not something you want to be doing for the first time. You'll also have to have the axle tubes shortened to A body dimensions, again Dr Diff.

Terry
 
Thanks, but would anyone know where to get the bearings, gaskets, seals so I can attempt to replace the old ones?
 
simply stated...Dr Diff... Cass is great...
 
DartThis74 said:
Thanks, but would anyone know where to get the bearings, gaskets, seals so I can attempt to replace the old ones?
Click to expand...

Dr. Diff can help you, great guy! or if your looking locally, Im sure an auto parts store can help with the wheel bearings, gaskets and wheel seals. Dr. Diff can get you the "green bearings" which is personally the way to go...others opinions may vary....Good luck!
:cheers:
 
You've got a a-body..thats a b-body rearend,you'll need to move the spring perches in, b-bodies perches are spaced wider apart...
 
Realistically I don't think you can get this done CORRECTLY for under $200. Are you sure it only needs bearings & seals or is that what you were told? The green bearings are about $100 by themselves. Differential kits are about $100. Can you press the carrier & axle bearings on & off yourself? Are the gears worn? See the $$$$$ adding up? Just my .02.
 
Pick up a copy of the Feb 2008 Mopar Action. There's an article called "When Pigs Fly" beginning on page 56 that will give you an idea on an 8-3/4 rebuild to evaluate if you want to tackle the job.
 
You don't HAVE to move the spring perches. One nice thing about moving perches is you can get the rear centered up in the wells. IMO, from an availability standpoint, the 66-67 B rear is the best alternative and closest width to an A rear in standard form.

Tons of cars have been running for years with the stock B spring perch location spread, 44" on centers, in an A body car 43" spring pin centers. Pull the spring out a bit and you can run it.

Why specifically do you feel it needs to be rebearinged? Is it locked up or really rusty inside?
 
Aaron and I picked up the rear end about 9:00 last night in the dark. We tossed it in my pickup and have not yet had time to look it over really good. The carrier was out of it, and the rear end was sitting out in the open in the trunk of a car.

I believe his questions are based upon our experience four years ago with the 7-1/4" for his Dart Sport we had done by a local shop. It cost Aaron about $200 for them to sand blast, paint, and freshen up with new seals (and I believe new axle bearings, but I'm not certain). We were quoted about $210 for them to do basically the same thing to an 8-1/4" rear end we pulled from our '73 Duster parts car. We thought we would use it before finding this 8-3/4".

Aaron and I were hoping to learn something with this 8-3/4" about working on rear ends (what makes them tick). If we can replace bearings and seals, and if we can install the pumpkin ourselves, then he will be money ahead on his project. Plus, we will learn something new in the process.

What he wanted to know is if there are any available resources (websites, books, service manuals, etc.) that someone can point us towards. I'm sure Dr. Diff can do a great job, but we have someone local to use, if we want someone else to do the job for us. Also, Aaron was wanting to determine whether the parts are readily available at Advance Auto, Mopar Performance, dealer, or aftermarket?

Anyone with experience or knowledge in working on rear ends (specifically the 8-3/4") please contact us.

Thanks much,
Jerry
 
If you don't have to change the pinion bearings it's cake to do on an 8 3/4.

You need a magnetic base, dial indicator and a stand for the pumpkin. Take a backlash reading, pull the caps/adjusters. replace the carrier bearings and reset backlash to the reading you got earlier.

If you have to pull the pinion, you need to get a depth reading before pulling it and reset it to the same afterchanging the bearings. Sometimes just swapping the shim pack will work, other times not.

If you have a Factory Service Manual, it will have detailed instructions.

This will give you a rough idea.

http://www.pirate4x4.com/tech/billa...Ring and Pinion installation instructions.pdf

Talks about how to adjust the 8.75 carrier bearing adjusters.
http://www.differentials.com/install.html
 
There ya go, that's what I'm talking about. Good information. That gives us a starting point.

Thanks
 
Are there any offset spring hangers or shackles available that will achieve the same results? We're only talking about 1/2" movement on each spring.
 
stroked 340 said:
If you want to do it halfass you don't.. if you want to do it correctly you move them!!!
Click to expand...

Spoken like the great learned person you are.

So mr. halfass himself... How those SIR rods working that you glowing suggested weren't an issue? :thebirdm:
 
'74 Sport said:
Are there any offset spring hangers or shackles available that will achieve the same results? We're only talking about 1/2" movement on each spring.
Click to expand...

To answer your question, please ignore the blowhard.

There have been quite a few A body cars run 10's, with a b rear, and not move the perches. I guess that's not good enough for some a-holes that know it all on this board. So why bore you with the facts.

To add to this, I guess I need to move the perches on my GTX because the pins are 43.75 apart and the perches are 44.08... QC was a strong point in 1968-69.

As mentioned you don't have to move them. If you choose to, that not a bad choice. You get the benefit of centering the axle in the wheelwells.

Sucks to have people that have real world knowledge and application of things in here and others that blow hot wind.
 
crackedback said:
Spoken like the great learned person you are.

So mr. halfass himself... How those SIR rods working that you glowing suggested weren't an issue? :thebirdm:
Click to expand...

Well mr. thinks he knows something,the rods are just FINE seems it was rod BOLT failure..and anyone who knows or seen my car will tell ya' nothing on it is halfassed..:thebirdm::thebirdm: right back at ya'...
 
crackedback said:
To answer your question, please ignore the blowhard.

There have been quite a few A body cars run 10's, with a b rear, and not move the perches. I guess that's not good enough for some a-holes that know it all on this board. So why bore you with the facts.

To add to this, I guess I need to move the perches on my GTX because the pins are 43.75 apart and the perches are 44.08... QC was a strong point in 1968-69.

As mentioned you don't have to move them. If you choose to, that not a bad choice. You get the benefit of centering the axle in the wheelwells.

Sucks to have people that have real world knowledge and application of things in here and others that blow hot wind.
Click to expand...


Yes,but its always best to do things the RIGHT way..from the way you talk your cars must be all mickey moused..:thebirdm::thebirdm:
 
I did my first R&P change and suregrip rebuild on a 741 and b-body housing - all after studying the types of articles and information already suggested. I bought an inexpensive dial indicator and made a spanner wrench for the adjusters. All of the parts came from Dr. Diff and yes I had the housing narrowed (for better wheel offset) and the perches moved. (By the way, not moving the perches simply puts more load on the bushings which is something to consider). I had old bearings removed and new ones pressed on by a machine shop.

Demon Seeds suggestion for help is wise. For me, everything turned out fine and if I can do it, so can you.

If you're not replacing the R&P it does simplify things quite a bit. That's because, on a 741 to set the pinion depth and bearing pre-load for new gears you have to R&R the pinion from the housing a number of times to try different shims. (Other rears use a crush sleeve to set the preload). The big main bearing on the pinion is pressed on. If a shim needs to be added under that bearing for proper pinion depth it can become a real chore. I took the old bearing that the machine shop removed and hogged out the center until it would just slip over the pinion. That way, I could try different shims until I got the depth right - then have the machine shop press the new bearing on with that shim. Pinion bearing preload is also adjusted using shims under the small bearing, but it can be removed by hand.
 
If it's just a case and axles, it's easy. Clean it, degrease it, sand/scuff the exterior, and paint it. The seals area easy to remove if you have a screw gun. Drill two small holes thru the existing steel seal body. Thread in a couple #8 2" screws, and use a pry bar or pliers to grab the screws. Pull easy and evenly, and it will come right out. No special tools. The bearings will require a press to properly remove and install. Also, make sure to order the seals on the axle flanges/end play adjusters, and gaskets for those flanges too. I'm assuming you have a center section for it already. I hope so, because they do take special tools, and if you havent done any, it's going to be frustrating...lol.
 
Yes, we got the pumpkin, but it was pulled out and sitting in the guy's shop floor. If I found the correct numbers stamped in the edge of the ring gear, it should be a 2.94 ratio. Not exactly what we hoped for (3.23), but it should be fine until something better comes along. It should be OK for those occasional trips between home and college Aaron will be making the next few years.

If it wasn't going to be a major undertaking, our intent was to freshen up what we can while everything is apart, before putting this car on the road for a test run. We've gotten good leads from some of you on resources to begin researching. Looks like we have a few days of homework to do. Aaron better get used to that real quick - he goes back to college next week.

Thanks for your input,
Jerry
 
Maybe these pics will illustrate why we believe that new seals are in order for this rear end. Ya think there was a leak, or what?

Seal Leak 01.JPG


Seal Leak 02.JPG
 
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