corp 12 bolt axle shaft length needed to purchase new axles

[pheengurs]

I need the stock length of the 6 lug 30 spline corp 12 bolt axle shaft length in order to purchase new axles...

I'm having trouble sourcing such specific info... and it's needed in order to purchase shafts...

any source that sells 6 lug axles seems to have around 3 different lengths of axle shafts ranging from 30-33 inches ...

anyone with a corp 12 bolt, 6 lug, 30 spline out there replace your axles? what lengths and company and strength type did you end up with?

thanks!

[Clyde65]

Call Summit Racing

https://www.summitracing.com/parts/c...CABEgJ69_D_BwE

[61K10]

stock k10 12bolt? staying with 6 lug?

[pheengurs]

thanks Clyde, the one you listed is for a C10, and is 5 bolt, but you are wise sir!

summit is listing the axle lengths on those and 'more' correct versions I'm looking for...

seems according to summit, the magic number is 30-3/4" ... I'm just not certain I believe it, and I don't feel like wasting gear oil trying to find out for sure, but perhaps that will end up being the case...


mine is a version 4 chev 12 bolt, and pretty darn sure its stock to my truck. I don't have all the data and numbers with me, but its a stock 3.73 geared truck, and I'm sure I matched the stamping on the axle... have it all written down somewhere...


and yeah 61K10, I'm sticking with the 6 bolt. For me I get no benefit from a 5 lug conversion. My other truck is an 07 canyon, runs the same 6 bolt pattern... I can swap rims and tires between my 64 and 07... how cool is that?

when I do get the new axles, I'll upgrade the lug size to the big fat ARP long studs (1/2"???) and she's also getting the old lift blocks removed and springs sized large enuf to compensate for that.


mainly I'm asking the community is because I am not trusting what I'm finding online... I've seen ranges of 30-1/2" to over 33" and when I dig further I see websites mixing sizes between a year range of 60-87, and 4 different carrier types for the chev 12 bolt...

currently, only yukon seems to list YA G3893605 as being the 'correct' length at 30-3/4" ... I'd like to somehow confirm that...

I've searched the site and the sticky's and haven't found what I need thus far... hoping y'all can knock it out of the park for me...

[mongocanfly]

I'm thinking the best thing would be pull your axle and measure....then there wont be any question
You can catch your dope in a clean container and reuse it if it's still fresh...

[Captainfab]

Starting with the axle flange to axle flange width of 62" for the '60 to early '70 differentials, subtracting the 1" diameter center pin and dividing by 2, I come up with 30.5" for a axle length. Without the correct length axles, your rear disc conversion will not line up.

[VictoriaHardware]

30.5" is correct. I purchased new axles from Moser for my '66 C10 and they did fit together as planned.

https://www.moserengineering.com/196...spline-30.item

They can also custom build them with different wheel studs, bolt centers, or 5-lug

[pheengurs]

well thanks for all the help identifying this folks!

axle length of 30-1/2 inches seems to be the consensus. Though it seems 30-3/4 inches are the only ones I can get my hands on, up here in Canada. Very frustrating...


I'm broke out the tape measure and trouble light and used CaptainFab's specs there... a rough 62" length was eyeballed from measuring under the truck with wheels still on, from outer brake drum to drum... ish... best I can do right now.

the reason I don't want to simply drop the fluid and pull the axles for an accurate measurement as I've just recently put a detroit tru-trac in, and am still during the new ring & pinion breakin 500 mile term... got 400 miles more to go, which for me is difficult as the specs say avoid highway miles. driving in town here in Calgary, with this old girl's currently sketchy brake setup, is stressful, the idiot factor on the roads is rather high here...

(thanks again CaptainFab for making those rear disc and brake booster bracketry, I'm eagerly awaiting their arrival so that brake upgrade project can get underway!)

and thanks everyone for the speedy and useful and informative responses that I always see here on the forum!