12 Bolt axle play

[SFTorange]

Hi All,

I was installing the rear wheel on my truck today, when I heard a clunk come from the differential when I pulled in and out on the wheel. I pulled the tire and brake drum off, and there is between 1/8 and 1/16 of an inch of play in the axle. When it bottoms out on either side, it makes the audible clunk. There is no gear oil in the differential, which would probably quiet down the noise, but I'm not sure what is normal. The driver's side has no play that I can tell. The axle is a junkyard piece, so I've never driven with it. Should there be any slop or play in the axles? It kind of makes sense given the c-clip setup, but the play seems odd.

Thanks!

[skoffice]

There should be a little play, from my experience. But 1/8" seems like too much. Maybe put a dial indicator on it and see if you can get an actual measurement. I'd say 1/16" is normal. But realistically both sides should have the same amount of play, seems odd the other side has none. If it were me, I'd pull the shafts out and check them since it's easy enough to do.

[Bugeyev8]

sounds like you need to replace the c clips on the axles, while you are there replace the axle seals too, I just did the ones on my 12 bolt and the axles move very very little now, don't go to Kragen or any big chain store for the c clips...they have no clue what you are talking about, I got mine from a rear end shop

[Rooster's 67]

I concur the C-clips are worn, allowing the axle to have a little more play than meant from the factory.

also check the axle clip groove for excessive wear. and replace the seals too

[**grumpy**]

Anyone have pics of how do pull n replace c-clips and seals? Ive done alot of things but never tore into a rearend. I just got a 72 12bolt to swap into my 66.
And best places to buy the needed parts
Thanks

[A.T. RockDriller]

No pic's, but it's a simple undertaking.
I'll walk you through it real quick.

1'st thing is to pull the cover.....duhh.
I should add.....jack it up to a comfortable height and put it on jack stands.

You don't need to pull the tires if you don't feel like it.
Roll the carrier around so that you can see the spider gears through the opening.
Locate the spider gear shaft (pin) and then look on the side of the carrier for the threaded allen head bolt that secures the pin in the carrier.
I think it takes a 3/16 allen wrench. Take out the allen head bolt all the way and set it aside. With the bolt out of the way, you should easily be able to slide the spider gear pin all of the way out of the carrier.
It's been a long time.....but going on memory, I think the pin only comes out one direction. Can't remember for sure.
Anyway, once you have the pin on the floor, you should be able to "roll" the spider gears out of the carrier. Keep take note of which gear was on the top (pin side) and which was on the bottom. Replace them as they were on re-assembly. Any way, under each spider gear, there is a concave thrust washer....Keep track of them....as sometimes they fall out into the drain pan and you might not notice....
So....Now, with the spider pin & gears out of the way, you can go around to the tire or brake drum....or end of axle and push it in....Towards the third member. that will push the C-clip out where you can slip it out of the groove in the end of the axle...Do it, replace with new clips and re-assemble in backwards order....Top it off with 90W stinky oil and drive it.
Good luck..

[Bugeyev8]

on most you will need to remove the drums to allow the axle to push in enough to get the c clips out, without doing so the drum hits the back plate before having enough room to get the c clip out, so the wheels do need to come off

Originally Posted by A.T. RockDriller

No pic's, but it's a simple undertaking.
I'll walk you through it real quick.

1'st thing is to pull the cover.....duhh.
I should add.....jack it up to a comfortable height and put it on jack stands.

You don't need to pull the tires if you don't feel like it.
Roll the carrier around so that you can see the spider gears through the opening.
Locate the spider gear shaft (pin) and then look on the side of the carrier for the threaded allen head bolt that secures the pin in the carrier.
I think it takes a 3/16 allen wrench. Take out the allen head bolt all the way and set it aside. With the bolt out of the way, you should easily be able to slide the spider gear pin all of the way out of the carrier.
It's been a long time.....but going on memory, I think the pin only comes out one direction. Can't remember for sure.
Anyway, once you have the pin on the floor, you should be able to "roll" the spider gears out of the carrier. Keep take note of which gear was on the top (pin side) and which was on the bottom. Replace them as they were on re-assembly. Any way, under each spider gear, there is a concave thrust washer....Keep track of them....as sometimes they fall out into the drain pan and you might not notice....
So....Now, with the spider pin & gears out of the way, you can go around to the tire or brake drum....or end of axle and push it in....Towards the third member. that will push the C-clip out where you can slip it out of the groove in the end of the axle...Do it, replace with new clips and re-assemble in backwards order....Top it off with 90W stinky oil and drive it.
Good luck..