I just bought a used 10 bolt from a buddy for dirt cheap. it has about 60k on it.... but a lot of 1.7 and 1.8 60 foots behind an auto within the last 10k miles.

I know the posi is strong, and the gears are in good shape, but what im worried about is worn axles. i have my current axle out of the car right now, and it seems that both axles have the same ammount of 'play' between the axleshaft and the pinion, however the new one makes a "clank" sound whenever the forces are reversed. I dont think it is full on fluid so that might be the cause. Is there anything i can check or is this just a roll of the dice?

I plan on re-gearing this rear end but i want to make sure its OK before i do. its going to take some punishment this season.

 

Do you mean the axle shafts and the side carrier (spider) gears? The "pinion" will remain rather constant along with the ring gear.

These tolerances tend to open up in time and contribute to the clunking out of the 10 bolt especially on the M6. I just installed a new 9" and was surprised how much tighter things were when they are new.

I am sure you already know this but punishment and 10 bolts do NOT go hand in hand. Good luck.

 

sorry i didnt word that the best.

rear end A: rear i just purchased
rear end B: rea from my car

On rear A, if i hold one of the axles in place and turn the pinion back and forth, there is a small ammount of play, along with a 'clanking' sound

On rear B, if i do the same thing, there is an equal ammount of play to rear A, but no clank.

My buddy (i bought it from) said he thought the gears on the axles were somewhat worn from his launches at the track, so im wondering if this is what the clunk is. And if so, is this an indication that this rear is not a good candidate for some more punishment?

Also the posi tests stronger on rear A than rear B.

 

that is play in the gears no the axles....

the only play axles should have is toward the center/straight out of the rear end...

you should also inspect bearing wear and pitting of the axles while you have them out...but what your talking about is the gear play. you can grab the part where the driveshaft goes and you should get the same amount of play in it...

 

I disagree with this. Again on a used rear end there will be slop where the axle inserts into side diff gear.

Pull the cover off, wedge or hold the carrier solid and turn the axles and you will see what I am talikng about.

My 10 bolt had a tight .004" BL and a ton of axle slop.
My 9" has a looser .010" BL and tight axles.
The 10 bolt rear had 3X the slop of my 9" due to the worn axles which caused clunking.

 

hmmm well ive had 2 years of 1.4 60' on my 10 bolt and theres no slop in th carrier....

ive got some gear play though

 

You should have gear play and it should be very near the backlash spec to which it was set up, this is normal.

If your axles have no slop where the splines insert into the side diff gears then you are clearly the exception and not the rule. I never measured mine but if I locked my carrier and slightly turned the axle back and forth there was a noticable and equal amount of slop in both. Its normal for them to wear like this.

Oh well.

 

im pretty sure any slop while locking the carrier and twisting the axle could be associated with movement of the spider gears within the diff.

if you are wearing out the splines of the axles to the point where there is any play whatsoever between the axle and the recieving splines on the spider gears, the rear is most likely junk.

 

yikes. replacing axles wouldnt fix this?

Next weekend i go home ill pull the cover and inspect it.