8 3/4 ring and pinion swapout

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Since you are disassembling, can you heat the nut with a torch or mapp gas, and try the cordless impact? My DeWalt impact probably wouldn't work, but my Snap -On of Milwaukee would
 

mopower440 said:
This is a 741 case, no crush sleeve.
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My bad, I thought I was responding to this comment,

" I did set up a 8 3/4 489 housing for a friend once, that I had the pinion nut torqued to 450' lbs and still had no pinion bearing preload. I tried tightening more, and pulled the threads out of the nut."
 
Illahe said:
My bad, I thought I was responding to this comment,

" I did set up a 8 3/4 489 housing for a friend once, that I had the pinion nut torqued to 450' lbs and still had no pinion bearing preload. I tried tightening more, and pulled the threads out of the nut."
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oh i got ya..lol..no worries
 
Illahe said:
A) do you have access to a welder?

B) be patient.

Weld a 3-4' piece of 1 1/4' black pipe to the Mancini yoke tool by slotting the pipe and welding on both sides.

Then get a 3/4 drive breaker at HF and the proper socket. Place the yoke tooling extension against your abdomen and fix the 3/4 breaker with pipe extension so you pulling towards yourself. Or rent a 3/4 drive impact from a tool yard.

Differentials are not scientific, they are just a pain in the ***.
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alright so i took your advice except the welding part because i dont have a welder. Last night i ordered a breaker bar from amazon and it got here this morning. I took a long piece of old exhaust pipe and cut it in half and put one half on thew breaker bar to hold the yoke and the other over the breaker bar breaking the pinion nut loose to make it longer for more leverage and put the pipe holding the yolk against my abdomen and was finally able to break it loose!! Thank you for the advice on that!! Got it all torn down including knocking out the races in about 15 mins. Now for the next dilemma..Trying to remove the pinion inner bearing without destroying it because i want to hone it out for mock up until i get the pattern correct. I bought this tool from Harbor freight and it sucks! The first problem is that the rampmis too steep to get under the inner race and its grabbing the cage so it will ruin the bearing. Second issue is that the threaded rods in the tool are not log enough to install the nuts to even use it! It might work on small bearings but not this.. Now what..I really need that pinion bearing off in good shape.

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You have the chunk removed. You have the correct socket. Run it by a tire shop and let someone zing the nut off with an impact. Then, buy yourself an air compressor and some air tools. Working on cars is an all or nothing proposal. In for a penny, in for a pound. I think the torque spec on that is somewhere between 240 and 300 FTLB. It AIN'T comin off with an electric impact.
 
mopower440 said:
man, theres no way i can swing another 200 for that tool. Gotta be another way
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I don't know what to tell you. If you were closer, you could bring it by here and I'd show you the way step by step. How close are you to the Murpheesboro area? I'm sure Tony Defeo would be glad to help if you asked.
 
mopower440 said:
alright so i took your advice except the welding part because i dont have a welder. Last night i ordered a breaker bar from amazon and it got here this morning. I took a long piece of old exhaust pipe and cut it in half and put one half on thew breaker bar to hold the yoke and the other over the breaker bar breaking the pinion nut loose to make it longer for more leverage and put the pipe holding the yolk against my abdomen and was finally able to break it loose!! Thank you for the advice on that!! Got it all torn down including knocking out the races in about 15 mins. Now for the next dilemma..Trying to remove the pinion inner bearing without destroying it because i want to hone it out for mock up until i get the pattern correct. I bought this tool from Harbor freight and it sucks! The first problem is that the rampmis too steep to get under the inner race and its grabbing the cage so it will ruin the bearing. Second issue is that the threaded rods in the tool are not log enough to install the nuts to even use it! It might work on small bearings but not this.. Now what..I really need that pinion bearing off in good shape.

View attachment 1716510467

View attachment 1716510468

View attachment 1716510469
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CLEAN the pinion bearing and gear good. Put them in the oven (while the o'l lady is making a grocery run) at 450+ and get some welding gloves on and slam the pinion threads down on a board with the nut on to protect the threads.

I've seen video's of mechanics heating a pinion bearing up and drooping it on the pinion.

Good luck!
 
mopower440 said:
Found this on amazon but not sure it will work with the 8 3/4 pinion bearing as its not labeled for that rearend and none listed for that
https://www.amazon.com/GXL-Carrier-Pinion-Bearing-Clamshell/dp/B01NAV0LUY/?tag=fabo03-20
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Seriously? 100 bucks? Boy, I can tell some of these guys givin you advice haven't a CLUE what they're doin and have probably NEVER touched a rear differential. All you need is something like this.

 
RustyRatRod said:
Seriously? 100 bucks? Boy, I can tell some of these guys givin you advice haven't a CLUE what they're doin and have probably NEVER touched a rear differential. All you need is something like this.

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RR, look at my post #31, i have that very kit and it doesnt work. The ramps are too steep so it grabs the cage instead of wedging under the inner race of the bearing and im trying to save the bearing so i can hone it out for setting up the contact pattern.
 
mopower440 said:
RR, look at my post up a few posts, i have that very kit and it doesnt work. The ramps are too steep so it grabs the cage instead of wedging under the inner race of the bearing and im trying to save the bearing so i can hone it out for setting up the contact pattern.
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You're not tightening it up enough You have to hunker down on it to get it to wedge under the bearing. I've been doin rear end work since about 1979. Some of yall are just unhelpable. Good luck!
 
RustyRatRod said:
You're not tightening it up enough You have to hunker down on it to get it to wedge under the bearing. I've been doin rear end work since about 1979. Some of yall are just unhelpable. Good luck!
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hell, you cant tighten it up because the threaded rods arent even long enough to put the nuts on it.. that kit is worthless on this! Im telling you, the ramp on it is so steep it will tear the cage up before it gets under the inner race. Yes, there are kits like this that will work but more expensive
 
mopower440 said:
hell, you cant tighten it up because the threaded rods arent even long enough to put the nuts on it.. that kit is worthless on this! Im telling you, the ramp on it is so steep it will tear the cage up before it gets under the inner race. Yes, there are kits like this that will work but more expensive
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So go to the hardware store and get some all thread rod and nuts and make it work.
 
Illahe said:
Hunt up an import bearing $11.40.

Cone: HM89449 & Race: HM89410 - Tapered Roller Bearing Set
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Im wondering if its even worth trying to hone the bearing to use for setup being its going to be different from the final new bearing i use so it will probably change measurements from the setup bearing.. Trying to figure out how to do this and get it close from the start so i dont have to tear it apart and press and unpress a hundred times to get it right..
 
mopower440 said:
Im wondering if its even worth trying to hone the bearing to use for setup being its going to be different from the final new bearing i use so it will probably change measurements from the setup bearing.. Trying to figure out how to do this and get it close from the start so i dont have to tear it apart and press and unpress a hundred times to get it right..
Click to expand...
mopower440 said:
Im wondering if its even worth trying to hone the bearing to use for setup being its going to be different from the final new bearing i use so it will probably change measurements from the setup bearing.. Trying to figure out how to do this and get it close from the start so i dont have to tear it apart and press and unpress a hundred times to get it right..
Click to expand...
Look on your new pinion gear, there is a measurement etched into the face above the pinion teeth. That measurement is the depth of the pinion that matches your ring gear (I'm assuming your using a new gear set).

The inner pinion bearing (honed) will allow you to manipulate the depth by shimming it or removing shims.

I'm confident that you understand the pinion depth procedure controls the initial 'set up' by now.

Once your confident that your pinion depth is in the ball park, put the outer bearing and a spacer then the nut. Install your ring gear and set the backlash. Past up the ring gear teeth and run a pattern. Then look at the engagement chart to see if the pinion is "patterning at the right depth."

Once the pattern is repeating itself at the right pinion depth, Pull the pinion out and press the "new bearing on" with the same shim stack that was under the honed inner bearing.

Re-install the pinion and ring gear, set backlash and run a pattern.
 
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Illahe said:
Look on your new pinion gear, there is a measurement etched into the face above the pinion teeth. That measurement is the depth of the pinion that matches your ring gear (I'm assuming your using a new gear set).

The inner pinion bearing (honed) will allow you to manipulate the depth by shimming it or removing shims.

I'm confident that you understand the pinion depth procedure controls the initial 'set up' by now.

Once your confident that your pinion depth is in the ball park, put the outer bearing and a spacer then the nut. Install your ring gear and set the backlash. Past up the ring gear teeth and run a pattern. Then look at the engagement chart to see if the pinion is "patterning at the right depth."

Once the pattern is repeating itself at the right pinion depth, Pull the pinion out and press the "new bearing on" with the same shim stack that was under the honed inner bearing.

Re-install the pinion and ring gear, set backlash and run a pattern.
Click to expand...
How do i use that etched number for setting this thing up?
 
mopower440 said:
How do i use that etched number for setting this thing up?
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That's the "ballpark" figure you shoot for regarding pinion gear depth. It's ballpark, because you don't go by that number, you go by the gear pattern. That number is just to get you close.
 
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