5 lug Axles Swap & disc conversion 68 complete posi

[zicc1835]

There are numerous older posts on this
I have read a lot of old posts and done much reaserch on this still have questions.
here is I want to do
replace 1968 6 lug axles with 5X5 axles c-clip 30 spline
convert to Discs that will recieve my 15" rallies
I dont want to use a different rear this one is in great shape 3.73
I dont want to source later model OEM parts from parts store
I dont want the big brakes ( not opposed to them,but pretty pricey)
autocityclassics.com has a reasonably priced conv. kit that works for me
There are many vendors to get the Axles from Mosner, CCP, ECE,POL Brothers etc. I have looked at them all
I looked into having my 6 lug axles converted ...this is a little bigger process than meets the eye weld up the 6 holes and drill the 5X5 pattern machine the center bore on a lathe to 3.08 get it to recieve the rotor and so it will center the rim on the axle..... may be less dollars and better fit if i just buy the conv. axles
So the questions
if anyone has done this dance can you tell me what the center bore diameter is on the 5X5 30 spline 30 1/4 length c clip axle and who you purchased it from?
I have a e-mail in to Auto City Classics to make sure the diameter of the slotted drilled rotor with e brake kit will be compatible with the axles .... so any info anyone can offer on this.. I got to believe someone has done this more recently than the old posts i have read thru ....
none that i have read say what size that center bore is on the conv. axles
Thanks for the help Happy New Year
Jess

[doc74021]

I bought a whole kit from early classic. On the rear end all I had to do was pull the 6 lug axles put new bearings in and slid in the 5 lug axles. That was it.

[yellowrallys]

I bought 5 lug axles from Early Classic years ago. I kept my drums until just a few weeks ago. Master Power Brakes in Mooresville, NC used my truck as a guina pig to put together a kit using late model Mustang calipers. It's compact enough to use with a 15 inch wheel. The rotor is about 11.5 or so in diameter They also hooked up the e-brake.

[Robznob11]

Well i actually went with the car bolt pattern and used 68 chevy car 11x2 drums from local parts store. Just opened up the holes for my 1/2 screw in studs with a hand drill. All the brake hardware is stock. If you call moser and tell them the year and make of the rear they will make the axles with any bolt pattern you want and they know what size to make the center. Same price. You can even opt for long screw in studs like i did. If you go 5 on 5 you can use stock 70+ drums. My advice is if you truly plan to keep it drag with 15's go with the car bolt pattern there are many more wide wheels that are lighter and cheaper for that bolt pattern. They also have better back space options. I dont remember the full part # but i got my car drums from mapa. I think the last 4 #'s was 1060.

[dell72]

Originally Posted by Robznob11

Well i actually went with the car bolt pattern and used 68 chevy car 11x2 drums from local parts store. Just opened up the holes for my 1/2 screw in studs with a hand drill. All the brake hardware is stock. If you call moser and tell them the year and make of the rear they will make the axles with any bolt pattern you want and they know what size to make the center. Same price. You can even opt for long screw in studs like i did. If you go 5 on 5 you can use stock 70+ drums. My advice is if you truly plan to keep it drag with 15's go with the car bolt pattern there are many more wide wheels that are lighter and cheaper for that bolt pattern. They also have better back space options. I dont remember the full part # but i got my car drums from mapa. I think the last 4 #'s was 1060.

Where did you find a front rotor with the 5x4.75 bolt pattern?

[GASoline71]

I bought Moser 5 lug conversion axles for my 1969 housing. $260 bucks with free shipping from Summit Racing.

Gary

[Robznob11]

Originally Posted by dell72

Where did you find a front rotor with the 5x4.75 bolt pattern?

I didn't need to I have a set of 15x8 draglites that are older and 5 on 5 bolt pattern. But if i change wheels I plan to re drill the front rotors if i choose to run drag style. If i go new updated I will pull the axles and moser will re drill them with the extra 5 on 5 pattern for 60 bucks. If you are debating. Have them drill both patterns and you can swap if you choose later.

[Robznob11]

Originally Posted by GASoline71

I bought Moser 5 lug conversion axles for my 1969 housing. $260 bucks with free shipping from Summit Racing.

Gary

Mine were just a tad more caus i pu 1/2 screw in long race style studs. If you talk to moser personally they can help you with the custom stuff😁

[68Gold/white]

Originally Posted by dell72

Where did you find a front rotor with the 5x4.75 bolt pattern?

Mid 68 til 70 full size chevy cars had disc as an option, and had the 4-3/4 stud pattern. I do NOT know though, if they are a bolt on deal...

There's plenty of room on stock 71-up rotors to drill 5 holes in the 4-3/4 pattern (the 71 and 72 rotors are the same as the 73-up...Make sure you have a competent machine shop do this, take them the studs you plan to use when doing so, AND make sure the studs have the proper shank length (the part in the hole of the rotor)

[ga-stepside]

Originally Posted by yellowrallys

I bought 5 lug axles from Early Classic years ago. I kept my drums until just a few weeks ago. Master Power Brakes in Mooresville, NC used my truck as a guina pig to put together a kit using late model Mustang calipers. It's compact enough to use with a 15 inch wheel. The rotor is about 11.5 or so in diameter They also hooked up the e-brake.

What year mustang calipers and what rotors did they use, are the 5x5 bolt pattern? I put Mustang calipers and rotors on my AMX but it uses the Ford bolt pattern, Better yet how can I get in contact with Master Power Brakes in Mooresville, NC to see if they are marketing this setup. ,

[zicc1835]

one more question ...what size are the stock rotors 11.5 ?

[CC69Rat]

( Not assuming you dont know.. but)

There were two different axle housings in these trucks. 67 through about the middle part of the year in 1970 had a more narrow axle than later in the 70 model year on through 87 I believe. The reason for the wider housing (.75" wider on either side, 1.5" total) for 70-72. .. (87?) was the introduction of front disc in 71. My opinion, in the later part of the year in 70 the plant just used what they had. I've had a 70 with the wider housing in it. Who knew .. of course it could have been changed at some point but it was still 6 lug.

Anyway, the first thing you want to find out is which axle housing you have. The way I measure is from the back side of one brake backing plate over to the other side in the same spot. If it's 55.5" long, it's an early housing. If it's 57" long it's a later housing. That's just an easy way to tell without even taking the wheels off the truck. (or for those pick-a-part trips)

The early 67-70 housings take a 30.5" axle if you measure from the end of the splines to the wheel mounting surface. (That's how Moser and others sell them, measured from those points)

70-up takes a 31 5/16 long axle. I know people swap them over all the time but there wasnt really ever a factory 5 lug early axle built as far as I know. Ive never seen one anyway. So if you have an early housing, really the only way you'll do it and do it right is to get conversion axles. I know they can be re-drilled.. but while youre rebuilding the axle, why not replace the seals, etc. internally. Also, the if the pin bolt breaks let us know there's an easy fix for that too.

Measure your housing first. It looks like the brake backing plates are already off.. so lets see which axles you need. I'm guessing early housing. I'd just go with Moser, have them machined down, it just takes a sec. Get the seal kit, and be done with it.

[zicc1835]

thanks to all ....ordered the Mosers....

[GASoline71]

Originally Posted by Robznob11

Mine were just a tad more caus i pu 1/2 screw in long race style studs. If you talk to moser personally they can help you with the custom stuff😁

One of the things I wish I would have done. Because the truck is gonna see track time this year and I will need longer studs. Have dealt with Moser in the past (before the internet) and anything you need is just a phone call away.

Gary

[lolife99]

Originally Posted by CC69Rat

( Not assuming you dont know.. but)

There were two different axle housings in these trucks. 67 through about the middle part of the year in 1970 had a more narrow axle than later in the 70 model year on through 87 I believe. The reason for the wider housing (.75" wider on either side, 1.5" total) for 70-72. .. (87?) was the introduction of front disc in 71. My opinion, in the later part of the year in 70 the plant just used what they had. I've had a 70 with the wider housing in it. Who knew .. of course it could have been changed at some point but it was still 6 lug.

Anyway, the first thing you want to find out is which axle housing you have. The way I measure is from the back side of one brake backing plate over to the other side in the same spot. If it's 55.5" long, it's an early housing. If it's 57" long it's a later housing. That's just an easy way to tell without even taking the wheels off the truck. (or for those pick-a-part trips)

The early 67-70 housings take a 30.5" axle if you measure from the end of the splines to the wheel mounting surface. (That's how Moser and others sell them, measured from those points)

70-up takes a 31 5/16 long axle. I know people swap them over all the time but there wasnt really ever a factory 5 lug early axle built as far as I know. Ive never seen one anyway. So if you have an early housing, really the only way you'll do it and do it right is to get conversion axles. I know they can be re-drilled.. but while youre rebuilding the axle, why not replace the seals, etc. internally. Also, the if the pin bolt breaks let us know there's an easy fix for that too.

Measure your housing first. It looks like the brake backing plates are already off.. so lets see which axles you need. I'm guessing early housing. I'd just go with Moser, have them machined down, it just takes a sec. Get the seal kit, and be done with it.

Excellent info.
You can also order Moser Engineering axles through Summit Racing.
And many times they have FREE shipping, which makes them cheaper than ordering direct from Moser.

[zicc1835]

Originally Posted by lolife99

Excellent info.
You can also order Moser Engineering axles through Summit Racing.
And many times they have FREE shipping, which makes them cheaper than ordering direct from Moser.

thanks to all who have responded... I have ordered everything specific to my application based on the info you have all taken the time to share
thank you