swapping out ring and pinion 7 1/4

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Slantsix64

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What tools will be needed? to swap the gear ratio out? also wanted to rebulild it with new seals are they still avaliable? bearing splicer, axle puller. and is it difficult to do, would i need a press? etc let me know thanks
 
According to the manual, you need a differential spreader to remove and reinstall the carrier in order to get the correct preload on the bearing.

There is also a special tool for measuring and setting the pinion depth, but I did my by trial and error with gear pattern marking grease.

Bearings and seals are available. You might have trouble finding shims.
 
According to the manual, you need a differential spreader to remove and reinstall the carrier in order to get the correct preload on the bearing.

There is also a special tool for measuring and setting the pinion depth, but I did my by trial and error with gear pattern marking grease.

Bearings and seals are available. You might have trouble finding shims.
I have a bunch of shims when you get to that point. All other parts are out there. I blew mine and took a year to finally find a new sure grip cheap.
 
Good luck this is not a simple task bought all new from US Gear and couldn't even get the radio to drown it out. Would start singing at 35mph no matter what we did or how we adjusted the shims. Grease showed a perfect trac. Complained and they sent a new one but got disgusted and put the original back in and quiet as a church mouse on the first try. Still sitting on that new gear. Had it apart so I decided to replace it with new guess new isn't always better. Try a fellow who calls himself Dr. Diff. If you cant find him on computer I will ck my records and come up with some contact info. He knows his stuff.
 
Good luck this is not a simple task bought all new from US Gear and couldn't even get the radio to drown it out. Would start singing at 35mph no matter what we did or how we adjusted the shims. Grease showed a perfect trac. Complained and they sent a new one but got disgusted and put the original back in and quiet as a church mouse on the first try. Still sitting on that new gear. Had it apart so I decided to replace it with new guess new isn't always better. Try a fellow who calls himself Dr. Diff. If you cant find him on computer I will ck my records and come up with some contact info. He knows his stuff.
What ratio?
 
The one I have is 3.55 brand new never installed. that's what is in my 64 cuda PM me if u want
 
I know the FSM says you need a case spreader, BUT!!! I have never seen a 7 1/4 that did not have carrier bearing adjusters. Just pull the axles, remove the adjuster locks from the bearing caps. Insert a "E" body torsion bar (or a rod with a 1 3/8 hex size nut welded to the rod) into the axle tube and loosen the bearing adjuster.
 
There were no adjusters in the housing in my 1965 Dart. I know this because I cleaned out the inside of the axle tubes with some gasoline and a toilet brush attached to a piece of pipe. Also the bearing caps did not have the threaded hole for the adjuster locks. There was also no mention of them in the 65 Factory Service Manual.

It sure would have been easier to get the backlash and preload set correctly with those adjusters.

I'd be curious to know what year the adjusters were added. And also to know if differentials will interchange between the two different style of housing.
 
I have no idea, what years had what. No way to tell if the rears were the same year as the cars. My 65 Valiant stock eliminator car, had the adjusters, and I bought the car in 1974. As for interchance, I would say yes, but have no personal experiance with the shim style housing.
 
MTSC says in '63 a spreader was needed, and the 7-1/4" was still a shims-type unit in '69. The '72 FPC shows the use of a spreader for disassembly, but the '72 FPC has a little box on page 3-1 (exploded view of 7-1/4" rear axle) captioned "1972 LATE TYPE" which shows an adjustor, lock pawl, and bolt. The '73 FPC shows only the type with the adjustor, lock pawl, and bolt, so there it is.
 
Once again Dan is the man with the straight dope. Thanks!

Any way to know for sure if the differentials interchange? I do know there is only one rebuild kit listed at Yukon Gear for a 7.25 which tells me they use the same bearings.
 
'70-'71 FPC says the 7-1/4" differential case is 2404 193 through "approx Aug '71" (then 3507 166), and the differential side gears are 2404 194 right on through.

'72 FPC says the 7-1/4" differential case is 3507 166.

'73 FPC says the 7-1/4" differential case is 3621 981 (side gears still 2404 194)

Given Chrysler's tendency to assign new part numbers to fit-and-functionally identical parts, this doesn't definitely answer the question; maybe give Dr. Diff or Randy's Ring & Pinion a call and ask.
 
'70-'71 FPC says the 7-1/4" differential case is 2404 193 through "approx Aug '71" (then 3507 166), and the differential side gears are 2404 194 right on through.

'72 FPC says the 7-1/4" differential case is 3507 166.

'73 FPC says the 7-1/4" differential case is 3621 981 (side gears still 2404 194)

Given Chrysler's tendency to assign new part numbers to fit-and-functionally identical parts, this doesn't definitely answer the question; maybe give Dr. Diff or Randy's Ring & Pinion a call and ask.
I always thought the changeover from shims was 73, but I recently broke down one from a 72 Dart..original to the car as far as I could tell, and it had the collars.
 
I have to question the change over years, for the shims. My 65 Valiant was bought in 1974, as a one previous owner car, with only 47,*** miles. I'm not saying the rear was never changed for a later unit, but think it is unlikely.
 
Um…Charlie, what you're saying, based on just a guess/assumption that one particular car probably might not have had a rear axle swap, is that all the evidence is wrong and Chrysler printed up detailed and completely inaccurate parts, service, and tech information year after year after year, for most of a decade. Nope, don't think so. The simplest explanation is most likely the correct one, and the simplest explanation is that your car had a later rear axle swapped in.
 
Dan, I agree. The only thing I know for sure is, I have been playing with 63-66 "A" bodies, since 1974. I have never seen a "shim" type 7 1/4. I have also never seen a cone type SG for the 7 1/4. Do you know if there is any number on the axle housing that could point to a year? I still have several 7 1/4 years, I could look at.
 
Several years ago, I purchased a cone type 7.25 Sure Grip from a member on this site. I can't remember what year he said it came from. He threw the bearing caps in the box and I don't remember them having the third hole for the adjuster locks.
 
Well, casting numbers aren't part numbers, but they're often close. Here are the A-body 7-1/4" housing P/Ns:

'63: 2404 073
'65: 2467 414
'67, 69: 2800 443
'70, '71: 3432 647
'72: 3432 647 "Without adjustor-type axle"
'72: 3683 958 "With adjustor-type axle"
'73, '74: 3683 958
 
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