HELP 8-3/4 741 case new stuff - price for setup - options

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RhinoMan68

if its for a 1968 cuda 'vert I probably need it.
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So rear end gurus of the FABO and Mopar REALM... Did I just REALLY screw up? What I've done...I bought a 741 case years ago had 3:23 gears non-SG, (I think I paid 50 bux)...was intact but even turning by hand I knew the front pinion bearing would have groaned. I took it apart and pressed out the tapered races. I bought a 3:73 Richmond set (everything I've got I bought from Dr. Diff (Cass is great))...and Timkin rebuild kit and shims as well as a SG-II from him and have been reluctant to press the races in the case again because not sure of too many things. So I reached out to a local (Front Royal Virginia) guy and he wants 730 bux to put all back and I guess I messed up by taking it down to nothing, if I hadn't he would charge me 450 bux...

I'm in need of a sanity check guys please tell me how stupid I am (already know) and maybe offer some options, opinions, thoughts??? Thanks!
 
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Wow. I'm thinking you should look for a different shop to put this together. I had a 489, 3.55 and SG assembled locally for $175.
 
Wow. I'm thinking you should look for a different shop to put this together. I had a 489, 3.55 and SG assembled locally for $175.
I hear you...that's part of what I'm asking about. How long ago was that? Did you have it apart (exploded view already) or together?
 
1650.00
  1. Check and streighten 4x 8 3/4 a body housings only 2 needed streightening
  2. Check 7 OEM axels
  3. Disassemble and reassemble 742 with new 3.23 ring and pinion, bearings, clutch disks, reused spider gears.
  4. Assemble, ready to bolt in.
I supplied the parts (thanks Dr. Diff)

Checking and streightening ($300 to $375)

So about 1300.00 ready to bolt in

I felt good about the price and outcome.
 
Read over and over the factory service manual until you can run the whole process through your mind. Not so daunting then.
Next, buy, borrow, parts store loan-a-tool as needed the dial indicator, a vice grip style indicator base, a seal/race installer set, caliper/depth gauge and go to town.

Drift/drive the races in carefully by hand with the installer vs. using a press.

Getting the pinion depth correct is the only tricky part (but there are ways to get it right using a honed out spare “new” pinion bearing and improvised measuring techniques) Believe it or not all you need to read and study is right there in the FSM section on the differential. Add any additional sources to supplement what you’ve already read in that. Once the pinion bearing is shimmed right all the rest you can just set up by the book, check, adjust and recheck and do it until right. For not much money. Time and effort, pride in doing it yourself. If so inclined :)
 
. Time and effort, pride in doing it yourself. If so inclined
I was going to do it myself too....

I had the parts for 4 years, I kept chickening out, yes im disappointed in myself but I can drive my dart with out fear I screwed something up.
 
I was going to do it myself too....

I had the parts for 4 years, I kept chickening out, yes im disappointed in myself but I can drive my dart with out fear I screwed something up.
Nothing wrong with that. Piece of mind:thumbsup:
 
Read over and over the factory service manual until you can run the whole process through your mind. Not so daunting then.
Next, buy, borrow, parts store loan-a-tool as needed the dial indicator, a vice grip style indicator base, a seal/race installer set, caliper/depth gauge and go to town.

Drift/drive the races in carefully by hand with the installer vs. using a press.

Getting the pinion depth correct is the only tricky part (but there are ways to get it right using a honed out spare “new” pinion bearing and improvised measuring techniques) Believe it or not all you need to read and study is right there in the FSM section on the differential. Add any additional sources to supplement what you’ve already read in that. Once the pinion bearing is shimmed right all the rest you can just set up by the book, check, adjust and recheck and do it until right. For not much money. Time and effort, pride in doing it yourself. If so inclined :)
Thanks as much as I get from reading, my dyslexia, my need to "feel it", and the amount of money I have already spent (I'm a cheap rat "bastage" and don't want to break anything) make it daunting. However I sincerely appreciate the words of wisdom and confidence you inspire....
 
Wow. I'm thinking you should look for a different shop to put this together. I had a 489, 3.55 and SG assembled locally for $175.
Man, 175 for setting up gears? Man, wish you weren't so far away as I'd let you set up gears for me and then give them to my customers after marking them up lol. All the shops around me (which isn't very many and I live near a very big city) charge double that at least these days and I haven't checked on their prices in the past year! And that's just for setting up the pig ready to bolt in and no more.
 
Just paid $300 in Connecticut. I supplied 3.73 gears, bearings and new sure-grip all from Dr. Diff. I was thinking of swapping them to 3.23’s though and I bet it would be less then the first $300
 
Taking it apart is irrelevant to the new set up. Nothing in the old set up really matters a bit other than possibly pinion shim thickness to start out with.

Most places have set up bearing or in the case you are dealing with, load the shims behind the rear race to set depth.

Shop rates are 60+ and most closer to $100/hr now. If it takes 4 hours, you have a number to work from.

They are not hard to set up. Just takes time and a decent spanner/press
 
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Not long ago I sold a; known to be quiet, very low mileage, 489 cased 4.30 chunk, with a 7290 Yoke, and a reconditioned "posi" in it, that I had personally set up and broke in;
for $450 Canadian ....................
The reconditioned Suregrip was worth almost that much.
I got NOTHING for my time.
But it was just collecting dust in the corner so, IDK .............
 
Not long ago I sold a; known to be quiet, very low mileage, 489 cased 4.30 chunk, with a 7290 Yoke, and a reconditioned "posi" in it, that I had personally set up and broke in;
for $450 Canadian ....................
The reconditioned Suregrip was worth almost that much.
I got NOTHING for my time.
But it was just collecting dust in the corner so, IDK .............
Dang...yup I think it was worth at least couple hundred more US than that.
 
IF you were local to me, I'd put it together for you and share a beer.
 
Going rate for a gear install around me is usually about $275-350. Without the prior pinion in it, it might be more since they have to actually measure to set the depth, but surely it shouldn't cost that much.

I've done a few myself over the years, I think when I switch to 3.23s next winter, I might just pay the guy this time. It's not a 'hard' DIY job, but you need to have a couple special tools for it, a dial indicator and a inch pound torque wrench to measure pinion rotating force, and it can sure take more than a few tries to get everything dialed in jsut right.
 
Call around to some Jeep/4x4 shops. They usually rebuild a lot of diffs and are more knowledgeable than the average shop.
 
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