14 bolt conversion drive shaft length

[goldengoat2]

On my 67 3/4 ton 4x4, I went from a eaton rear to a 77 14 bolt ff, my original drive shaft is about 1/2" too long and the spare one out of my 77 parts truck , the yoke is too large diameter, what a'm I to do?? shorten the original, or is there a nother alturnative? thanks for any imput. o yea ,it hase a 4" lift

[DieselEater]

You should have a slip yoke of some sort in it right??? If it allows a total of 6 inches travel both directions without slipping out or bottoming out, and you have a half inch from center....than you should be fine.

If you have a half inch from slipping out...than you need 3 1/2 inches. Long is easy.....short means custom...i.e.$$$. Just cut and re-weld where you want it. It shouldn't cost much to have it balanced.

I know I didn't help you any.....but felt the need to reply.

A......

[DirtyLarry]

Yeah, my shaft is too long too. (well, not that shaft)

After doing the ORD rear shackle flip a while back the rear drive shaft slip joint is pushed in all the way. In fact, I just pulled the tcase and transmission out of my 78 K10 to fix all the pesky oil leaks and actually had to lift the rear of the truck up with a bumper jack in order to get the rear drive shaft out.

Here in Pueblo we have a great shop (Pueblo Brake and Clutch) that builds and reworks drive shafts. I have had my shafts reworked a few times already due to tcase swaps, trans swaps, lifts, etc and they are pretty reasonable with the prices. To shorten a shaft it is around $75 including balancing. Lenthening shafts are much more costly.

If I were you I would just have a drivetrain shop shorten the original…..Or you could by a bastard U-joint and possibly get the 77 shaft to work. My 78 has a ½ ton driveshaft and a 14FF connected with a bastard U-joint.

[earl87gta]

hows the rear sit in the fender wells alot of times with the shackle flip it pushes the rear forward some. you could use a zero rate in the back it would give you 1in more lift but you could use it to move the axle back 1in in the fender wells and then no drive shaft work needed.

[DirtyLarry]

The rear wheels are centered in the wheel wells, the truck sits level (now), the kit corrected the pinion angle and all that jazz….. But, I actually had to remove one leaf spring on each side from the packs as it sat way too high in the rear after the ORD shackle flip. I installed 6” front springs at the same time I did the ORD 4” rear shackle flip. The rear springs were a special concoction anyway that I had a spring shop make up several years ago in an effort to get rid of the lift blocks when I was running a 4” lift. No zero rate spring needed here.

[earl87gta]

Better to cut it then. Im trying to decide on my ride hight now so when I get my new drive shfts nade it will be the kast time. I had my blazer shaft done 3 times. Im hoping to do the burb once and be done with it.

[goldengoat2]

Got a price today for shortening the shaft, $140.00 sounded high to me. What if I cut 1" off the front Smaller drive shaft imput shaft?? the shaft seems long and it,s bottoming out against the rear yoke.