usmc320

iTrader: (3)

I did a search for the u-joint size needed for the slip yoke for my 4l80e using the stock driveshaft. Some threads said 1310, some said 1330, and one even said not quite a 1310 but didn't list a size. Can someone tell me what is the correct size? I think it is probably a 1330 but am not positive.

BTW, I talked to Drive Train Specialists today and they gave me this as the correct yoke for the 4l80e if the u-joint is a 1330 series. (This is for the output shafts splined all the way.)

http://www.drivetrainspecialists.com...duct-2464.html

This is the one that was referenced through the stickies as the correct one:

http://www.drivetrainspecialists.com...duct-5557.html

There are 2 key differences that I see.

1. The u-joint sizes are different 1330 series vs. mechanics 3r series

2. Length 6.76" center to end vs. 8" center to end (which would make sense the OP from that thread had to cut the yoke down, because it was too long)

Anyway, I thought I would pass that info along. I am getting ready to order, so if anyone could verify the u-joint size it would be greatly appreciated.

ShevrolayZ28

iTrader: (4)

I'm hoping that these will work for me. (stock drive shaft to 4l80)

1350 yoke:

http://store.summitracing.com/partde...5&autoview=sku


conversion u-joint (3r to 1350):

http://www.actionmachineinc.com/1350...leu-joint.aspx

usmc320

iTrader: (3)

Thanks for the links. So you're under the impression that the stock driveshaft u-joint is the mechanics 3R, i take it?

The guy at drive train specialists seemed pretty adamant that the 2 were not the same or interchangable.

Anyone that can clear this up? I'm surprised nobody can answer this with a definite.

ShevrolayZ28

iTrader: (4)

I know the 3r and the s44 use the same size u-joint. The 3r is an Inland Empire part (Same co that makes our aluminum drive shaft.) and the S44 is a Saginaw part.

But why do you want to stick with the 3r or S44? You can go with most any yoke that is the correct length and spline. 1310, 1330, 1350 etc. The conversion is made via the u-joint, with one end fitting the 3r drive shaft and the other end fitting whatever size yoke you choose.

usmc320

iTrader: (3)

Right, but I still need to know the stock u-joint size even to get the correct u-joint conversion to fit the driveshaft side. Plus if I'm ordering a yoke I might as well just order the correct size, so I don't have to have oddball u-joints. If I already had a yoke for the 4l80e I would go conversion u-joint to make it work.

I'll have to check with the local auto parts stores and see if they stock the conversion u-joints for 1330 to 3R. Thanks.

ShevrolayZ28

iTrader: (4)

Are you also planning to upgrade the drive shaft or the rear end someday?

What I did was buy the 1350 yoke and installed it on the stock 3r drive shaft with a conversion u-joint. I'll run the car like this for a short time, then, once I have the 9" installed, which also uses a 1350 yoke, I'll measure length and order a Strange chrome moly shaft with some nice 1350 u-joints. When I get the drive shaft, I'll swap over the 1350 slip yoke.

FWIW, the part number for Neapco 1330 to 3r conversion u-joint is 2-1569 for greaseable, and 2-0793 for sealed.

http://press.kscdirect.com/?p=843

Good luck...

Mike101

iTrader: (3)

very informative I am in the middle of my 80 swap hoping to have it running in a week or soo

usmc320

iTrader: (3)

Thanks again for the info.

MRZ28

iTrader: (15)

So....What would be the corect U-Joint using the Stock DS?

ShevrolayZ28

iTrader: (4)

With which yoke?

MRZ28

iTrader: (15)

I believe the one i would need is the 1310. the one that isnt splined all the way.

usmc320

iTrader: (3)

Well it appears the driveshaft size is mechanics 3R. If you want a yoke to match the stock driveshaft that's the u-joint size you should look for.

I think I'm going to take ShevrolayZ28's advise and get the 1350 yoke and appropriate u-joint conversion, since I will eventually upgrade the rear axle and driveshaft.

MRZ28

iTrader: (15)

Does that yoke come splined all the way?

usmc320

iTrader: (3)

I am assuming so. You might want to call Summit or Drivetrain Specialists to confirm.