Rear end clunk turning left

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340Duster247

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Hey guys jumped in the duster today and notice every now and then when making a hard left turn from a stop I get a clunk from the rear drivers side. Feels like rear end noise. It only clunks/pops once during the turn
Also I sometimes notice black tire marks on the ground following that tire.( rear end isn't welded locked).
I bought the rear used. 489 case. Posi clutch style. 4.30 gear. Running 315/60/15 tire.
Any thoughts?
 
Did it work ok for a while then just start doing this or did you just install it and it's doing it? Does it have limited slip additive in the gear lube?
 
How about a little history. Was this plug and play? Did you have it apart?
 
If it worked for a while and just started it's apparently locking up. Why is the question. A common failure area is the spider cross pin. If it has broken it could let the spider gears walk and lock up. That's my only guess.
 
Thanks fishy. I'll dive more into it tomorrow after work. Put the rear end in last season,(barly drove it, just broke in engine) everything worked fine. Been working good this season no noise at all , just notice it last night, now did it a couple times tonight. Oie :s
 
Still doing it every now and then on sharp slow turns. When it's happening I'll look back at the tire, and it's acting as if the rear end is welded locked. Today I went for a burn and it did the loudest pop, bang , clank yet. ... I've lifted one side of the car of the ground(rear) so one tire was touching and one tire free to spin, put it in neutral and could not get the free tire to spin(slip) at all. My buddie says this isn't normal what are your thoughts.
Don't know a lot of history on rear. Got it from a local reputable used parts guru,
 
How old are the leaf spring front eye bushings?

Mine does the same thing, I have clapped out old leaf springs. Might be time for some new ones!


It could also be all that circle tracking your doing!


[ame]http://youtu.be/mnutXjBt6LU[/ame]
 
Hahaha well bushings are new but ill check for wear. I have a feeling something is broken too. If I open this rear up what should I be looking for?
 
Pull your axles ( and I mean all the way out) don't leave them hang on the inner seal.

Pull the pig and look for chipped gears, could be R&P or something inside of the suregrip itself.

IF your R&P appear to be in good shape, STOP, there are some steps that you need to do BEFORE you pull the suregrip out if you intend to run those gears again. You might be able to see inside it enough without pulling it from the pig to see if something is broke.

Is this a clutch or cone?
 
Look here:

http://www.moparts.org/Tech/Archive/axle/13.html

This will give you a general idea of how each one is designed. It's quite possible the clutches are shot, one or more of the gears inside is broke etc.

Like I said ( I can't say it enough) if you have to tear into it and have never done one, there are a few steps to take before you remove it from the carrier if your R&P are in good shape and you want to reuse them, quietly I should say.
 
Ok thanks My buddy has rebuilt a clutch style before so ill have a little help. I'll keep you guys posted
 
Just a few things to do:

Mark bearing caps so they go back on in the same orientation.

Using a dial indicator fixed to the center section get a backlash reading on R&P. When you assemble try and get it as close as possible to what you had or you will be howling.

If it's in the suregrip itself, there won't be any need to disturb the pinion (good thing).
 
my guess is chipped spiders in the clutch posi....symptoms match mine and when i pulled mine i could spot chipped teeth through the small openings in the unit.

i hope not tho because i have no idea where to get good replacements.
good luck!
 
The best and most affordable place to buy parts for the 8 3/4 is Dr. Diff, he ships to Canada no problem, google him. Sounds like broken spider gears for sure and they are reasonably easy to change for anyone with a little bit of mechanical ability.

Good luck
 
Thanks a lot guys!! Gonna pop it out tomorrow. I'll let everyone know and we can go from there
 
I'm going to guess it is clutches not releasing. I would add another tube of Posi lube or fish oil and take it to a parking lot and do figure 8's. If it still pops on the turns I would then pull it out and inspect for some sort of mechanical damage.
 
Ok I'll try that too... It came out of nowhere, and only does it once in a while. Would you guys recommend adding more additive or draining it all and using synthetic?
 
Ok I'll try that too... It came out of nowhere, and only does it once in a while. Would you guys recommend adding more additive or draining it all and using synthetic?

Add more additive. Why spend $25 on 2 bottles of synthetic when a $5 bottle of additive will accomplish the same thing? If the additive doesn't do it something mechanical is wrong and if that's the case I'd bet on spider gears or a cross shaft is broke. Dr. Diff sells a kit to replace them if you need it
 
Ok I'll try that too... It came out of nowhere, and only does it once in a while. Would you guys recommend adding more additive or draining it all and using synthetic?

My 95 3500 Cummins 4x4 would do this from time to time. It had a clutch type Dana 80, I would add a bottle of additive to it and it would be fine. They tend to grab or chatter more when under load and turning.
 
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