my new 9" rear has a Strange yolk that requires a 1350 u-joint. My driveshaft now is the stock driveshaft that connects my c4 to my stock 8inch rear. To connect this driveshaft to my new 9" rear do i just go to the auto parts store and buy a universal u-joint? I don't have to have anything welded on do i? i want to drive it around now but im eventually getting an aluminum driveshaft which is why i'd just like to buy a universal u-joint if that's possible.

 

you'll probably need a conversion U-joint from 1350 to probably 1310
one axis of the U-joint you currently have is just hel dwith c-clips in the driveshaft. The other axis sits in the pinion yoke and is clamped there with U-bolts.

you will need to measure what you currently have in the driveshaft and just buy a conversion U-joint from that to 1350.

in a 8" rear I suspect a 1310, but the problem here is that 1310 can have two different measurements.


the length from cap end to cap end is 3-7/32" (most people measure incorrect and claim it's 3.25")
then the other important bit. the diameter of the cap.
It can be either 1-1/16" and 1-1/8". I've seen both with 1310 spicers

so lets assume you measure 1-1/16" at the cap diameter in driveshaft and 3-7/32" overall length (from cap end to cap end) then you probably need somethiong like this:
http://cgi.ebay.co.uk/220741659774/?...389831&afsrc=1
how to measure is explained in article.
you should be able to get such joints in any car part place in the states

Kalli

 

I don't know what U joint you need but I got a good chuckle when you spoke of a Universal U-Joint which would be a Universal Universal Joint. I thought that was pretty funny.

 

You want a hybrid u-joint

https://www.napaonline.com/Catalog/C...010270151&An=0

 

thanks guys. so kalli, i have to measure the axis that is sitting in the pinion yolk and connected with u-bolts? i havent gotten a chance to get under the car yet so it's hard to picture what you're talking about. i do understand the measuring instructions you gave me. ill get back to u with those measurements asap

 

unless i know for a fact im keeping my c4, then i can just get an aluminum drive shaft with a 1350 u-joint on the end and i won't need a conversion right? does anyone know where to get a balanced aluminum driveshaft?

 

Hiya,
yes you can get a balanced aluminum driveshaft at Dennys driveshaft.
However they are measured to size. you cannot order one before you have the rear end in place. and it'll take a few weeks to make up.
But for putting the new rear end in there you won't need that.

The new rear axle you say is 1350. so we don't need any measurements from there
The old rear axle is uninteresting to measure as you are going to remove it.

So what you need to do is to match the current driveshaft to the new rear axle.
the axis of pinion is uninteresting (as said this is going to be removed). you only need to figure what you have sitting in the driveshaft. The axis that sits at rear of driveshaft. you need to get exactly that with a conversion to 1350 (your new rear).

What you need to measure is the diameter of the eye that holds the u-joint in driveshaft. It's either 1-1/16" or 1-1/8"
if it's 1-1/16" then 99% sure the part BA Mustang quoted will suit you.
if you want to be 100% sure, measure the length of the U-joint axis in the driveshaft as well. from cap end to cap end. It should be 3-7/32"

kalli

 

thanks kalli. ill let you know how it turns out!

 

Let me tell you a quick story. A few years back I upgraded my center section to a Strange Nodual with the Daytona bearing package. Great rearend. I also upgraded my toploader to the large output shaft and upgraded the u joints because of torque monster issues. That gave me a 1330, I think on the front and a 1350 on the back. Every since, I have had issues with some strange vibrations and noise. A month a go, I got mad at it and started fixing rattles looking for the issue. It looks like the culprit was the drive shaft being a big too long for that setup. I am having the driveshaft shortened and balanced today. I will know Thursday if that fixed the issue after I replace u joints and get it remounted. My point is you may want to check the length of your driveshaft if you are upgrading u joints. The 1350 is very strong, but it is bigger and so is the strange housing so you may have some yoke slip issues that you need to check. My drive shaft is so tight, it is very hard to get it in and out currently.

 

Cowboy, thanks for that information! i will definitely look into that. Im just not sure what im going to do with my driveshaft. I've read that for high horsepower motors, even though aluminum helps reduce rotating mass, steel is better because it flexes less. I also don't know what im going to do with my transmission. I have a c4 now but i truly want a top loader. i just dont know where to find one that wont break my wallet and im a little unsure if i can handle the conversion myself