• When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.

Rear end clunking

scaputo3

Active Member
Local time
10:53 AM
Joined
Aug 22, 2012
Messages
36
Reaction score
3
Location
new jersey
I have a 69 roadrunner with 323 posi. When I make left turns I hear a double “clunk” coming from the right rear (sounds like the axle..not sure) this only happens on left turns. No gear whining or other noises. Gear oil changed about 1000 miles ago. No leaks from the pumpkin or rear axles/ wheels

Any suggestions/recommendations are appreciated
 
Depending on the style differential it may need an anti friction additive.
 
Sure Grip clutch going, or is it the cone style...and I suppose that would just stop working and not make a noise?
 
Clunk from right rear axle? You changed the gear oil 1000mi ago? I assume you pulled axles and drained the pumpkin? Did you set the axle end play?
Hi.. yes pulled the axles, drained the pumpkin. Did not set end play by dial. Axles went back in without issue and were snug. After c clamps installed axles seemed fine.

Would not setting by dial cause an issue after this much time has gone by?
 
'69 'Runner would have 489 rear end with cone clutches. They can wear in such a way that that cone bottoms out in the carrier. This could be the cause of your noise.
 
'69 'Runner would have 489 rear end with cone clutches. They can wear in such a way that that cone bottoms out in the carrier. This could be the cause of your noise.
Thank you! Would I feel it if the rear is suspended and I try to move the wheel up/down/side to side?

If that’s the issue what is the fix?

Thanks in advance for the feedback
 
You might have one tire that does not hook up: one wheel peel. I saw an article in an old Mopar magazine that mentioned facing off the small end of the tapered cone, so it could fall deeper into the carrier without bottoming out. Another article did not recommend doing this, because this can allow the mating side gear in the differential to move out of proper mesh. They said there was no real good fix for the cone-stye carrier, other than replacing it. If this is the problem, it might be time to change to the clutch disc style SureGrip carrier found in 742 cases. They are interchangable.
 
You might have one tire that does not hook up: one wheel peel. I saw an article in an old Mopar magazine that mentioned facing off the small end of the tapered cone, so it could fall deeper into the carrier without bottoming out. Another article did not recommend doing this, because this can allow the mating side gear in the differential to move out of proper mesh. They said there was no real good fix for the cone-stye carrier, other than replacing it. If this is the problem, it might be time to change to the clutch disc style SureGrip carrier found in 742 cases. They are interchangable.
Thanks again!
 
Hi.. yes pulled the axles, drained the pumpkin. Did not set end play by dial. Axles went back in without issue and were snug. After c clamps installed axles seemed fine.

Would not setting by dial cause an issue after this much time has gone by?

By a dial indicator is good to get it if you are not comfortable doing it by feel. My FSM lists the procedure as removing all end play, then backing the adjuster off by 2-4 notches.

I'd get your end play sorted and then see if you still have noise from the right rear.

Edit: this is assuming you have regular and not "green" bearings.
 
Last edited:
I think ‘cranky’ knows the answer. He’ll probably chime in soon. Little bit of machining is needed.
 
Yeah, I believe that @Cranky mentioned that he had revived a few cone style units in the past.
 
Auto Transport Service
Back
Top