Hey guys, i am investigating an issue with the rear end of my 1970 chevelle. It has been down for about a year and a half with no motor while i build the new one. I have also moved twice. Well now the car is in the garage next to the finished motor and things are moving.

When looking at the car though it appears that one of the axles is sticking out of the rear end housing further than the other. I first noticed it by the tire sticking further out. I then checked and the brake drum is also sitting further off the backing plate than the other side. I am going to pull apart the rear end to make sure nothing is catastrophically wrong and measure the axles. I ran this rear end for about 3-4 months before the car went down, but i dont ever remember it being off length wise, i never experienced any problems with it. What is the proper length of a standard 12 bolt axle in a 70 Chevelle. This rear end has an eaton posi with standard c-clips, thanks guys!

Daniel

a 66-67 is 29 5/8"

I think I recall that 68 on has a wider track

Doh, forgot to mention its a 1970 dated 12 bolt, so it has the 68 and above length. Editted, Thanks!

Bump, anyone know?

According to the Hollander, it should be 30 5/32 " . I'm not sure how it is measured though. I would think it would be over all length, but may be C-clip to flange.

Axle lenght 64-67 29 9/16", 68-72 30 1/16. Itīs measured over all lenght.

It may be because someone put an axle saver on it. When I tore mine down, I found one and it protruded from the end of the axle about 1/8th of an inch or so. (Took several hours to extract that puppy!)

Interesting, what exactly is an axle saver?

Daniel

The axle bearing will have nothing to do with how far the axle sticks out. The c clip and axle length controll that. Malibu ss 64 has the lengths correct.

Possibly, that side does not have the c-clip eliminator pressed on where it should be - it may need to be pressed in a touch further.

Hey guys, i posted the other day asking about proper axle length for a rear end in a 70 Chevelle. The codes on it at CKD 122B2 i believe. Now i noticed one of my brake drums sticking of the rear end further than the other so i decided to pull them. As you can see below both of the axels are sitting on the ground and the bottom plates are even. I also showed a pic of the brake drums to show you how each one of the rotors sit on the brake pads. The longer axle as you can see actually rides on the outside edge of the drum, while the shorter axle runs inside the area on the drum like i think its supposed to.

Notice the length difference, you can use the line of the tool box for reference.
http://www.chevelles.com/showroom/data/500/Pictures_001_Editted.jpg

Notice how this one runs on the outside edge
http://www.chevelles.com/showroom/data/500/Pictures_003_Editted.jpg

Notice how this one runs more inside the drum
http://www.chevelles.com/showroom/data/500/Pictures_006_Editted.jpg

Now the confusing part here is that supposedly the correct axle for my rear end is the longer one that makes the brakes not even fit in the drum. When taking it apart though i didn't have a lot of clearance getting the c-clip out of the shorter one, where as i had lots of clearance to shove in the longer one and get the clip out.

I dont know of any or the shorter (before 68) rear ends with CKD codes on them, that fits a 70, but it seems to work better with the shorter axle for the brakes! It also keeps my tires from rubbing on the wheelwell whereas the side with the longer axle has problems. I dont think there would be any detriment to running the shorter axle style, all the bearing surfaces seem to be in the right spot.

The axles are overall 1/4 of an inch in length different. From the end of the axle face where the drum sits, to the opposite tip the shorter one is 29 15/16 and the longer is 30 3/16. Let me know what you guys think on what to go with and what to do. Obviously i need new axles whatever happens, need to have a matched set. Thanks guys!

Daniel

I beleive the shorter axle is from a 67-69 camaro. the 30" is the correct length for the rear end. You can go to Toms differentials.com and do some further research and get replacements. Moser also sells some stronger axles that are better also

RandyB..
71 chevelle 468
67 camaro rs/ss

I had bought a used '68-'72 12 bolt rear in 1980 with the exact same problem. While I was installing it I noticed one axle rode the brake pad approx .375 furthur out on the driver side. You could see daylight between the drum and the backing plate. I never found out why because the side that stuck out furthur snapped the first weekend I raced it. It came apart 4" from the inside end which was not good since I did not have c-clip eliminators. I slipped a new axle from an old '68 - '72 rear and it fit correctly.

I learned never to race if every part of the car does not look 100%. The only thought that I had at the time was that it was not a 12 bolt Chevelle axle. I thought that it might have been from the Olds 12 bolt that has a 10 bolt carrier or from a full size car. Maybe now I will find out.

Tom

Daniel, don't know if this will help you or not but I have a set of 10 bolt 68-72 axles that you can measure yours off of if you wanted to? I am just a few min from your house and can run one over, let me know.

Oh, I am having a pot luck BBQ for this swap meet at the end of the month as well. Think about attending, it's a good time :)

The axle bearing will have nothing to do with how far the axle sticks out. The c clip and axle length controll that. Malibu ss 64 has the lengths correct.

Duh! I wasn't thinkin' straight when I posted about the axle saver - my bad!:clonk:

Thor, that might be a good idea. I dont know if i can do it today because of some plans, but let me know and i might just swing by and hold one up against the other or to compare and see what is right. I appreciate all your guys help and feedback.

Daniel

Tom S, The Olds axle will not fit in the Chevy 12 bolt because the Olds axle has a pressed on axle bearing, where the Chevy axle is retained by a c clip.

Daniel, If your 12 bolt is a '68 to '72 then the axle should be 30 1/8 inches measured by hooking a tape on the axle flange and going to the end of the button on the other end. Stick the tape in the axle tube and hold it against the cross shaft in the differential. Measure to the outside edge of the brake flange (not the end of the tube) and add 2 3/4 inches to that. This will give you the correct axle length for your rear end.

BGH,

I forgot that the olds bolted on from the end. They probably have 28 splins also.

Using you supplied measuments the overall length of the housing should be 54.75 plus the diameter of the cross shaft. The overall length of the assembled rear from wheel mounting surface to wheel mounting surface should be 60.25 plus the diameter of the cross shaft, plus two times the thickness of the drum.

Would you know the cross shaft size and do these measurments seem correct. The reason I ask is I am having a rear cut down and I made all my measurements off a 10 bolt that was in the car. The calculations are 'amout to be removed' and now I want to make sure the 12 bolt is calculated as over finished size.

Thanks
Tom

The cross shaft is 3/4 inch. This will give you a total width of 61 inches without the drums. I think your measurements are correct.

Alright, so i am going to buy new axles. Now what brand do you guys recommend? I was just searching the summit website for reference and they had moser's and superior's. I have heard of the mosers before and hear they are reputable stuff. Now the superiors i have also heard of but dont necessarily remember any opinions on. The superiors also come with new bearings and wheel studs for abotu $10 more than the mosers bare. Is there a brand/source you guys prefer for axles. This is a 427 BBC car with a 2400 stall in front of a th400. 3.55 gears with a posi. I plan on racing the car as a weekend warrior and i plan on putting slicks on it, but even then i dont think i need somthing beyond a basic performance aftermarket axle. Thanks for your help so far guys!

Daniel

I recently installed the Superiors in my car. The bearings were Timken (a good thing). I had to install the studs which was no big deal as I have a hydraulic press. I am pleased with these axles. They do not taper in the middle like the originals. The reason I went with this brand is that I've read more than a few posts about the axle studs breaking on the Mosers.

I have sold a lot of Moser axles, and as far as I know there have been no problems with any of them. I usually sell them with the studs installed.

Is it feasible to just install the studs with a hammer and some type of anvil, or do i need to find someone with a press, or just order them that way. I also checked out Tim's Differentials and their KA Axles. The pricing is very similar between all the brands.

Daniel

You can install them with a hammer, but there is a better chance that you could damage the axle.

buy a wheel stud installer tool. It is no big deal and takes a lot less space than a press.