Driveshaft help
 

trying get a new drive shaft for my 67 suburban with the LS swap 4l60e. I'm thinking the best thing is to get the yokes and u joints ordered and then have the tube made. I still have the original donor truck driveshaft and the original suburban driveshaft, but I'm thinking new yokes would be best? does anyone know the part numbers for these? the slip yoke from the trans and the corresponding driveshaft yokes (trans and diff)?

also, will a 1 piece driveshaft be ok to replace the original 2 piece?

Re: Driveshaft help
 

You can run a 1 PC shaft, but its gonna be larger diameter than a 2 piece..I'd always use 1 shaft if possible...less moving parts..I'd get up with whoever is gonna build your shaft..they'd be the best info on what you need..I went all new when I had mine built..

Re: Driveshaft help
 

The shaft needs to be welded and balanced. Maybe you can do some of the work. Are you trying to save cost by buying the parts yourself? Unless you are a certified welder and have the means to balance the shaft, just find someone to do the shaft for you and tell them what you want. Only exception if the vehicle is off road only. Whomever you get to do finish work on shaft will probably eliminate any difference in savings if there are any. Common practice adding cost to estimates on projects where customer provided their own parts or labor due to unknown problems. I do pretty much everything myself. The driveshafts for my truck were ordered and not done by me.

Re: Driveshaft help
 

oh... right when I said get the tube, I meant get it welded it up too. I don't know why I didn't say that the first time. I just feel sometimes when you let a shop gather the parts they charge you more for those parts than if I found them on my own

how much in diameter do you guys think would work with the stock TA crossmember? the truck is on air ride too so it seems like a big diameter driveshaft would be a tight squeeze

Re: Driveshaft help
 

When I took my driveshaft in to have it shortened a bit, the shop said I needed a 3.5" diameter and it was 54" long on a SWB C10 with 6L80 trans. Mine is currently 3". He said with 3.73 gears and 28" tires, it would hit critical RPM at 80mph. After that, it could start whipping like a jump rope. I did not get a new one as I rarely go above 80, but I had it to 90 with no vibration.

So I am guessing with a Suburban and the length of your shaft, you are looking 3.5" - 4".

Re: Driveshaft help
 

A friend of mine ordered one from this company and it worked out great behind his 4L60e and 12 bolt rear.

https://www.southwestspeed.com/index...ub=Driveshafts

Re: Driveshaft help
 

I was going to order one from southwest speed, but ended up ordering mine from Action Machine

https://www.actionmachineinc.com/pag...oke-order-form

I got a 3.5" aluminum with upgraded 1350 size U-Joints to go from 4L80E to my 12 bolt rear that I swapped to a 1350 size yoke. It didn't cost too much more except for the upgrade to forged chromoly yoke

Re: Driveshaft help
 

On my hot rod projects I always upgrade to 1350 u-joints and yokes. A good drive shop will ask the length, max engine rpm and do you want solid or greaseable u-joints? I would buy the trans/rear axle yokes from some place like Summit. Let the drive shaft shop supply the u-joints and the yoke ends of the drive shaft.

Re: Driveshaft help
 

I checked around summit and found the slip yoke for the trans. they had a bunch listed but this one says 27 spline 1350 and it's a decent price

https://www.summitracing.com/parts/str-u1662


for the diff yoke I put a filter on for 67 suburban and found this one with also the 1350... not entirely sure what spline mine is

https://www.summitracing.com/parts/s...rban/year/1967

Re: Driveshaft help
 

i sent a message to dennys driveshaft and they recommended i run a 2 piece because of clearance with the stock TA crossmember, but they do not make 2 peice driveshafts. i also checked the above 2 links and did not see any 2 piece on there either. i think the air ride and the stock clearance for the TA crossmember is causing some odd problems. i really wanted to go with a 1 piece but doesnt seem ideal

Re: Driveshaft help
 

When I shortened the C30 frame ,I used a 2pc ...I only shortened the rear section of it..the 1st section stayed as it was...maybe you could do similar

Re: Driveshaft help
 

well, to be honest... I was thinking about that. but how would a slip yoke for a 4l60 be welded to the smaller diameter stock driveshaft? I mean, technically I could bolt up the carrier bearing and the rear yoke should bolt up too. the front one would need to be shortened I guess?

but my original concern with a 2 piece was that I thought it made it much harder to get the drive angles correct... as opposed to just trying to match the front u joint angle to the rear u joint angle?

this truck will never be amped up to high horsepower or some crazy driving and burnouts, I don't really care for that stuff. I just want something that works and won't break lol

Re: Driveshaft help
 

Somebody mentioned it above, but try this place. They made me special driveshafts for my Jag rear end.

https://www.actionmachineinc.com

Maybe they can weld a yoke on the front driveshaft that uses a u-joint with different sized caps. I see a lot of those lately.

Re: Driveshaft help
 

Kev2809, there is a guy on the north side of Houston that does all my driveshafts and he has never done a bad job. He is a small one man shop that is very affordable. Been around for over 30 years. The name of the shop is Gilberts driveshafts. Berry rd and Fulton just north of berry. He does it all.

Re: Driveshaft help
 

If I were you, I would take some measurements of your setup and take the driveshaft you have to the local shop and see what they could do for you. (Action Machine website has some articles about measuring)

My plan was to do that since I had my trucks original driveshaft and my donor vehicle driveshaft. I ended up ordering the one piece 3.5" diameter aluminum(The larger diameter was because I was borderline on being too long for smaller diameter). I ended up having the driveshaft hit the top of the trailing arm crossmember when the suspension was fully compressed(6 inch rear drop). I cut the hole bigger in the crossmember and made a stiffener to add to the crossmember. Might should have stuck with my original plan to use 2-piece.

Re: Driveshaft help
 

Find a shop local to you and work with them, and let them build it, at least let them quote it complete. If you don't know a shop ask the local trans or heavy truck shops who they use. They can spec you a conversion u joint so you can use the 4l60 yoke from the donner truck on your stock shaft, although it should slip right on if you had a TH350 originally. Then ask them what kind of measurements they want and have them shorten or lengthen your rear shaft. If you're not a high horsepower drag strip build I wouldn't be worried in the least bit about spending money on forged yokes and converting to 1350 joints un needed. Use solid, non greaseable u joints, they are stronger.

Re: Driveshaft help
 

I had a local 4wd shop do a couple for me, including a 2pc...fleetpride did all 3 for my IH

Re: Driveshaft help
 

thanks for the answers guys. I actually have dealt with a driveshaft company for my tandem axle dump truck. they have made a drive shaft for me before, but I wasn't too sure if I should let a shop like that handle something like this. they make some big ass driveshafts lol

Re: Driveshaft help
 

PM sent
Gilbert does it all

Re: Driveshaft help
 

just dropped it off with Gilbert. he's going to reuse my stock 2 piece but he suggests adding a slip shaft on the driveshaft between the carrier bearing and diff. havent seen that before on these swaps. he said it will help with in and out movement when the truck goes up and down.

he builds a lot of driveshafts fr shorty's hydraulics here in Houston. but I'm thinking those guys hop those cars and that's why it's needed?

Re: Driveshaft help
 

You need a slip because with your air ride set up, you have a lot more suspension movement than what is generally seen in a factory vehicle. In stock form, the amount of in and out can be taken up buy the yoke in and out of the trans. When there is the potential for a lot of movement, a slip shaft is beneficial to keep the driveshaft the correct length at all times. You'll have no issues from it, especially with you not shooting to become a speed demon or make huge power numbers.

Re: Driveshaft help
 

thanks for the info. when I got back yesterday I did search around the forum and seen a post that mentioned using a slip shaft with a 2 piece and air ride. so I called Gilbert and told him to go ahead with it. should get it back this week so I'll post them up

Re: Driveshaft help
 

seems like it fit like a glove! haven't had a chance to try and set it at ride height and check the angles just yet but it looks good

Re: Driveshaft help
 

Spicer has a good angle calculator on their website for figuring u-joint angles.
Get yourself a digital angle finder on Amazon that has a magnet on it.
Works great.

https://spicerparts.com/calculators/...gle-calculator

Re: Driveshaft help
 

I had a problem using the calculator at first. Guess others may have used it incorrectly as well. Pinion pointing up is actually down. The calculator is looking at the angle from the starting point, not the component. Another tip, if you have a digital angle finder first zero it on the frame for accurate measurements. While the working angle is the only thing that is important. Always good to start with an accurate starting point