drive line/u-joint help

[dukcaln]

so I swapped motors and transmissions this week. I ditched the TH350 and replaced with a TH400. Same size motor, sb350. I found a complete drive line out of a 72 that had a factory TH400 and figured it will match right up.Which it did other than the u-joints on the factory TH400 are larger than the ones on mine that I removed.

So the situation is the rear end has the smaller spline for the smaller u-joint. I was told napa auto sales a u-joint that has the two sizes built into one u-joint. Anybody ever done this?
I thought I might be able to split the drive lines and use the back half of mine with the front of the factory th400 section but it looks like the spline with the carrier bearings are different?

Hope I am clear with waht I am trying to explain without pics

[mixermike]

I believe they are called a combination joint....I have one on in my 57 chev truck. My rear u joint is 2 different sizes because I have a mustang rearend under it.
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[dukcaln]

combination u-joint, ok thats a start, we dropped it off at the local napa auto parts/machine shop in hopes they can match it.... anybody know the standars c10 and c20 and or small block th350 vs th400 size. long bed

[Shyguy]

Some places also call them a "Jump Joint".

[PanelDeland]

If you have both U joints out,you should be able to measure them and cross in a U joint manufacturers data.The parts store should be able to do it EZ.If they can't,look for an old school parts guy.The other place to find them is in a 4X4 shop.They do axle swaps all the time and run into the same issue.

[dukcaln]

om thanks..... I was hoping someone had the standard u-joint size for the rear u-joint on a th350 drive shaft vs the th400 shaft... the th350 shaft is a smaller ujoint compared to the th400 shaft.... is the ujoint on the th350 shaft a 1310?

[brad_man_72]

You probably need a 1310 to 1330 conversion joint. I'm sure you can find a decent quality neapco or spicer made joint someplace besides your local auto supply. If not try online, precision and house brands SUCK!

You may be better off taking your shaft to a driveline shop to have it checked out. It may need more work than you know. Have them check the joints, support bearing, straightness and ballance.

I've been building driveshafts for about 5 years. I don't know everything but I know way too much about driveshafts.
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[dukcaln]

brad, I have been searching the internet all night and came to the conclusion I need either the 1310-1330 or 1310-1350. But it seems the 1350 were 14 bolt rear ends and more likley the combo is 1310-1330. However, the drive line I picked up is a complete driveline from tail to shaft from a 67-72 long bed with th400, so its hard to say if its 1330 or 1350, but at least I am pretty positive its one or the other.... napa has them in stock in my town, the precision PUJ353 premium universal 1310-1330 and or the PUJ348 1310-1350.

thank you. I figured somebody on this board has done the th350 to a th400 swap and had to do the drive line swap using a driveline from a 67-72 that had the factory th400....

[huahuamick]

Think I may be in love with this

[jjzepplin]

I am doing this swap too. I went to Napa and got the 1310-1350 and it was the right size on one end but the caps were too big on the other. My old u joint was pretty new so I took two caps off it and put them on the new joint and boom there you go. So I think 1310=1330 is the one. However I am not impressed with the quality of the new joint so it will be replaced with a spicer or neapco. The new caps were loose. All of them. Go figure. Put the old caps on the new joint and they were much better than the new ones. Never again!

[mixermike]

I agree with brad,the percission joints suck....get neapco if you can
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[dukcaln]

thanks all, the precisision will be to get here going and on the road, I will swap to a better u joint as mentioned...... seems the choice will most likley be the 1310/1330.... they have the driveline at the shop so I am sure it will be matched... dand Holiday today and all will delay a coiuple days... but hope she is back and running by Monday!

[brad_man_72]

1310 and 1330 have the same size caps.
1330 and 1350 are the same width.

For those planning to swap out your precision joints keep the box, they have a lifetime warranty so you can go get your money back from the parts store.

It also helps to have a shop install the joints, someone experienced will be able to easily get the play out of a good ujoint wich will make the joint last longer and the ballance will be more accurate.
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[dukcaln]

so got it figured out and the drive shaft is in... turns out I needed a 1310/1350 combination ujoint

now we hope to fire the ole truck back up tomorrow

[mixermike]

Good to hear
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