Traded center section out today.need some help identifying

[65fordguy]

I met a guy at a mustang car show a few weeks ago.. he mentioned he wanted a 3.70 rear end.. I couldn't help but ask what he had.. he replied about a 3.08.. ( did they make those in 9" ) so I of course said.. hey thats what I got.. he returned with wanna trade.. so we struck a deal.. and made good on it today.. once I got there his noticeably looked beefier.. thicker.. stronger.. he called it a Daytona center section.. but, I think he really is referring to the pinion support style...?? anyway.. my truck from the factory had a 240 6 cylinder and it was a plain jane truck.. the axle was not as stout looking at all.. My guess is being that its a 31 spline axle housing, may of came out of a muscle car or FE powered car or larger truck.... maybe 4x4 ?

can you guys tell me more about what this thing is? as far as I can tell it will fit fine.. just looks different.

Thanks.

[6166 Junkyard Dog]

Ford did not do a 3.08 in Ford 9", also if its a 31 spline will not work in your truck,, also blowing smoke a Daytona center section thats a joke if it was special one thing it would have a big N on the housing, not here unless its a posi then be worth something even if its a good ratio I don't think you can exhange the ring and pinion from 28 to 31 spline 31 spline center sections we throw away since so many of them unless its a low gear for 4x4 trucks

[banjopicker66]

A little more information about your trade will help, can you post the casting number of the case?
Have you tried to count the number of teeth on the gears? That will tell you the ratio.
Check this website out, it is full of good stuff, but I do not know enough to verify everything he says.
http://www.kevinstang.com/Ninecase.htm
I bet that hooded lip on the pinion prompted the seller's "daytona" comment.
Tom is right about the spline count.
Our Slicks came with 28 spline axles, and trucks after '72 had a mix of 28 and 31 spline. We can't use axle shafts made after '72 (mostly 31) axles because they are too long.
The only 31 spline axle that would have the correct length would be one from a '68-'72 9" axle housing - but I have never seen a 31 spline axle made before '73. It would be a very rare piece indeed.

[65fordguy]

ok.. my bad...I was told our trucks were 31 spline..I never counted them.. just went off what I was told years ago.. I put my axles in it.. so whatever mine was, it is. I took the axles with me to the swap to make sure of that. I sorta assumed a lot of it was smoke blowing.. and not that I really cared about any of that.. I was just interested in the gear... so, after inspection and counting the teeth and doing the math... 44 ring 16 pinion.. It looks like I have a 2.75 .. which I am ok with.. whole reason Im doing this is so I can keep up with my buds in there AODs ... casting numbers.. on the back of the case just inside the lip.. c7aw E 45... on the carrier? ( what the gears are attached to ) c6aw dwacc <--that last bit was hard to read..may of not got it 100% . . . I attached a couple markings on the case that I found.. one looks like casting information other looks almost like a trademark.. or crap in the mold.. but above that mark is an upside down 45... which also on the inside of the case as well.

[Hawkrod]

Just a minor point, not all special center sections have an N on them. The heavy duty centers came out in 62 and the N was not added until late in the fall of 68. Many "experienced" Ford guys have walked right past a pot of gold by looking for the N. If the casting number on the inside of a 9 inch center housing starts C2AW or C4AW it is special whether it has an N on it or not. Also note that the Daytona pinion support is very special and has nothing to do with the housing (it is the smaller part bolted on that the yoke is on). The one in the picture is not a Daytona style but many trucks did have them (especially heavy duty 4X4's) and I will buy them! They have a C5AW number on them and a machined ring around the bolts. They also use a special yoke. Hawkrod

[65fordguy]

Thanks for the info hawkrod ... about that special yoke! ... I obviously knew it was different but failed to measure it.... once I got the section mounted I noticed the u joint I had was a good bit smaller... my first reaction was well crap.. I gotta get a different end on my driveshaft.... which isn't a horrible thing, I am going to have to have it rebuilt... dang exhaust people mounted a muffler too close and it rubbed the shaft while articulating.. has a nice worn spot on the shaft..... that all said.. is there a u joint that I'm not aware of that will mate these two or will I just need to have a new rear put on my shaft? if so do you know any info about the yoke so when I take it to the shaft guy he will know what I'm working with?

Thanks for the info.

[65fordguy]

I may of answered my own question... after many visits to an old time driveline guy.. he has to be 80 nearly.. and still kicking out shafts daily ... he made reference to a hybrid 1310 to 1330.. is it likely that the yoke on my new rear end is a 1330? assuming I remember correctly that the old one was 1310..( shaft came from a 75 f100) Guess I'll have to measure it up when I get back home from work. That would make life easier.

[banjopicker66]

Several U-joint sizes have been standardized for years; there are only a couple.
Various sized yokes like this one have been used for years on the same pieces of equipment such as driveshafts, transmissions and rear axles.
The 4x4 rock crawler and Jeep guys often use mis-matched transmissions and rear axles in the attempt to make the "perfect" machine, and therefore end up needing U-joints that can mate up to differences between driveshafts and yokes that normally wouldn't be found together.
The solution is what your friend called a hybrid U-joint, and what I know as a conversion joint. It is made so that one crossmember is one dimension, length and diameter of the cap, but the other cross is made to a different size. This other one may be shorter, or with a different cap size.
This allows mis-matched connections to be made without having to change the yokes.
On your differential yoke: Measure the length of the shaft inside the yoke, and the diameter of the cap across the open half. You will also need a set of U-bolts.
On the driveshaft - Take the same measurements.
Take these down to the parts store and they can get you what you need - 1330 is just one designation of one of these conversion joints.
The box auto parts stores will probably not be able to get you what you need, you will most likely have to go to a machine shop, or a store like NAPA or CarQuest.

[65fordguy]

Thanks Banjopicker... I may give our napa a shot.. but in past they haven't been much, if any, better than autozone or oriellys ... but, they do have the books and what not to find stuff.. just not sure they have the know how to find it.. There is a couple driveline shops including my friend around.. but he is around an hour away. The one in town is more of a large truck service shop... but, has a spin off that does drive line and springs.. I'll go out and measure the yoke and shaft tonight.

[62galxe]

this will give you some reading. conversion ujoints are at the bottom of the page.
http://www.therangerstation.com/Magazin ... joints.htm