Nothing snapped and nut still on. Never had a hard time with u joints unless they were rusted so I included the pic.
8 3/4 Clunk/Yoke Tightening Advice...
- Thread starter mrmolding
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Ah! Thanks!!! That would have been bad!!!
68-500
Well-Known Member
Don’t tighten the nut to 175lb ft I did that after replacing pinion seal and ended up snapping the pinion shaft bearing preload to tight and welded bearing to race. 175 lb ft is to crush the crush sleeve. Good and snug for the nut in pinion.
STOP. This unit needs to come apart if it actually has 1/8"-1/4" fore/aft movement. There is no crush. Ask yourself why? You need to take it apart and look. Is the crush sleeve over crushed, loose, is there pinion bearing damage, did the pinion shim disintegrate? All are possibility's that need to be addressed if you don't want issues that will occur shortly.
Doug
Doug
Thanks! I think I’m going to remove the unit and take a look. Holding the yoke and trying to tighten nut on ground is challenging without help. Seems easier to fix removed and reinstall in my case. Very glad all of the responses told me that something is wrong!
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Anything new on this?
I bit the bullet and bought a new Dr Diff 489 case and his Sure Trac II. Should be getting here in a few days. I crawled under the car after my last message and figured I’d have an easier time just replacing everything since all paperwork from last 20 years does not mention rear end work. I’m also massively distracted by my 73 “Driveway Find” Roadrunner (see other thread by me). The 73 was completely apart with no parts and I’ve been hunting for literally everything from door rods to good hinges to bumper guards. Really looking forward to Spring Fling this weekend too so I’ll post updates on the new rear once I get it back together. Thanks again for all of the help!!!
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Ok, can't believe it's been a month since I started this thread, but here are some updates. Got the original one out last night and the Dr Diff with Sure-Trac II is ready to go in. The original didn't have too much play but enough that I could rock the yoke a little so it seems like it was ready for refurb. I am wondering if this is the original set of gears...any thoughts are welcome!
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Jan 18th '73 is the mfg date on them..
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Yup, I'd say original gears....and looks like a cone type SureGrip. Uh, don't scrap it. I (and others here) refurb those....
I was wondering that! So it is a 70 Road Runner, must have been swapped at some point! Thanks!
It's the one in this post:
https://www.forbbodiesonly.com/mopa...lsey-goodyear-polyglas-radial-fr70-14.211553/
I actually got it from mowch1 about 1.5 years ago. Been a lot of fun!
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The vast majority of the 'high performance' cars were bought off the lot and most dealers were more interested in making a buck than outfitting the cars with the 'right' performance add ons like a limited slip differential and most kids that were fortunate to acquire these cars back in the day had no idea what an LSD was (maybe they knew what the drug was) and if they did, they ordered the car with one. Heck, I didn't really know what a 'positrac' was let alone what a SureGrip was when I was 18 lol but I quickly found out. So yeah, it was common for someone to find one at a wrecking yard and buy it and add it to the car. When I did an engine swap in my 66 Belvedere in 70, I found a 3.91 along with a 727, and headers from a totaled 69 Bee in a wrecking yard but it wasn't an SG. Also found out that adding weight to the right rear helped then installing air shocks and filling the right rear with 20 or so psi vs the left rear also helped. The car laid down twin tire marks more often than not and much more than not on a level surface.
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The Sure Grip was a very inexpensive option on the cars in the 60's put
pretty expensive to put together thru parts. I only occasionally found a
car on the lot ordered by any of our local dealers with Sure Grip! We bought
a 70 Cuda with a 440/6 with no Track Pack and 3:23 Open Rear new in 70.
pretty expensive to put together thru parts. I only occasionally found a
car on the lot ordered by any of our local dealers with Sure Grip! We bought
a 70 Cuda with a 440/6 with no Track Pack and 3:23 Open Rear new in 70.
I think they were about 55 bucks.
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I've ordered two trucks in recent times (if you call 92 and 2000 recent) and both were ordered with limited slip rear ends and 3.92 gears. One was a 92 Dakota and the other was a 2000 Durango both with the 5.2 engines. Back then, there wasn't many American vehicles that got either one of them off the line.....including the Mudstain GT.
I used one of these, and it helped A LOT.
Got my build sheet and after a little searching here, it looks like the car did come with a 3.23 Sure Grip. But at some point someone replaced part of the gears due to the date stamp of 1973. Once again, thanks for all of the help with this everyone!
Found this here in another post here:
056 = axle assembly number = B body, 8.75 rear end with 3.23 gears and Sure Grip, 11" drum brakes
and on the build sheet:
Found this here in another post here:
056 = axle assembly number = B body, 8.75 rear end with 3.23 gears and Sure Grip, 11" drum brakes
and on the build sheet:
Hey everyone, I wanted to give an update. New Dr Diff unit and clunk is gone. That turned into a transmission mount issue and tranny mount bolt issue from work done by a PO. All fixed and now done and the Tranny shifts are great! Amazed it’s been this long since I finally got it out for a test drive, but I wanted to say thanks again for all of the help!!!
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