hack n tap or shimming first for measurments help asap only ride at moment!!!!

[PoorManXj]

I am in the process of installing a hack n tap using front drive-shaft for rear. My concerns with this is im supposed to measure out 33 3/4 from the rear yoke to output shaft but when i shim wont that throw measurements off? I would shim first but when i cut the shaft down that will throw my angles off. Should i remove the rough country shims when installing my new shims? they look as if they are about 2* shims from rc. I have 4* and 6* shims. I am also running iro 1.5 to 2 inch lift shackles.....can someone help me out asap!!shaft only has 3 inches of plunger movement so im thinking this might be important to get right

 

[dfarmxj]

I got away without using shims with a 3" aal and 1.5" shackles. I also ended up cutting the shaft shorter than the instructions said to in order to have the d/s not fully compressed.

So, in short, cut the shaft a smudge long (easier to cut more off than to put it back on), test fit everything and see where to go from there.

I definitely recommend cutting and drilling with the engine running and the trans in reverse, but don't try to tap it with the shaft turning.(don't forget to chock the tires)

Good luck! It's a pretty easy and straight forward deal.

 

[PoorManXj]

thanks but question is i havnt shimed yet so the drive shaft will compress some when i shim wouldnt i need to cut it shorter not longer? and for everything else i have researched this is my only question really

 

[PoorManXj]

drilling with engine running wont that like break my wrist or somthing or the bit ....that wouldnt be to fun
:wierd:

 

[dfarmxj]

I'd just install the h&t and see where it ends up before worrying about shims. The driveshaft has plenty of slip in it to make up for a fraction of an inch on the output shaft.

At least try drilling with it running. It's not bad, just don't push too hard or try to drill too fast. The only way to get it cut and drilled more perfectly is to pull the output shaft out and chuck it in a lathe.

Just fyi, mine is an auto/ c8.25, so if you have a different axle or trans your experience may differ a little from mine.

 

[VAhasnoWAVES]

i think your over thinking this... IDEALLY you want to cut the output shaft as short as possible, and install a drive shaft that fits what you need. but...

thanks but question is i havnt shimed yet so the drive shaft will compress some when i shim wouldnt i need to cut it shorter not longer? and for everything else i have researched this is my only question really

the length change will be minimal with degree shims... if the drive shaft is so compressed/extended when you install the H&T that a few degree change in pinion angle is going to fully compress/extend it beyond its limits your shaft isnt right to begin with. what would happen if you hit a bump or drooped the axle?

drilling with engine running wont that like break my wrist or somthing or the bit ....that wouldnt be to fun
:wierd:

actually... its a genius idea.

you remove both drive shafts, put the jeep in 4low, and put it in reverse. the spinning tail shaft creates a lathe effect. you will make your cut super strait, dont forget to chamfer the edges. then, as your drilling, you will VERY easily be able to tell if you are off center. that shaft is hard as shit, unless youve got some super drill bits, your not going to catch and grab on it. cutting oil is your friend.

 

[PoorManXj]

well i was gonna cut it while running just drilling sounds like a broken bit ....anyway now my problem seems to be that the drive shaft is gonna be to compressed....doesnt make sense because its supposed to work with a low pinion late model front driveshaft. and yes thats why im worrying about the measurements because it looks so close. how much slip does it need im about 5 inches in the back with 8.25 and np231

 

[PoorManXj]

well i was gonna cut it while running just drilling sounds like a broken bit ....anyway now my problem seems to be that the drive shaft is gonna be to compressed....doesnt make sense because its supposed to work with a low pinion late model front driveshaft. and yes thats why im worrying about the measurements because it looks so close. how much slip does it need im about 5 inches in the back with 8.25 and np231

i ment with high pinion:wierd: 97 to 99....one i got was one off my front axle so i know what i got...i also got one off a 98...the same shaft

 

[VAhasnoWAVES]

well i was gonna cut it while running just drilling sounds like a broken bit ....anyway now my problem seems to be that the drive shaft is gonna be to compressed....doesnt make sense because its supposed to work with a low pinion late model front driveshaft. and yes thats why im worrying about the measurements because it looks so close. how much slip does it need im about 5 inches in the back with 8.25 and np231

the shaft and drill bit will be spinning in the same direction if i remember correctly. the once you have it center punch the bit will self center. this isnt something that you just bear down on and drill away...

if it looks like its too compressed, them cut the tail shaft shorter. if thats not enough, there is a spicer PDF floating around with make/model/year of all vehicles that came with double cardan drive shafts. find something that fits. if an auto drive shaft is too short, something out of a manual should fit the bill.

 

[PoorManXj]

the shaft and drill bit will be spinning in the same direction if i remember correctly. the once you have it center punch the bit will self center. this isnt something that you just bear down on and drill away...

if it looks like its too compressed, them cut the tail shaft shorter. if thats not enough, there is a spicer PDF floating around with make/model/year of all vehicles that came with double cardan drive shafts. find something that fits. if an auto drive shaft is too short, something out of a manual should fit the bill.

thanks man how bout that spicer pdf...i googled it earlier but ill look again....can i run this thing in 4wd with rear shaft removed?

 

[dfarmxj]

My driveshaft is compressed a bit more than I'd like right now also, but I couldn't get the axle to sag enough to fully compress the shaft, so I left it. I cut the output shaft off enough that to get it any shorter, I'd have to cut the yoke down also. It's been over a year and no problems so far, but I don't get to wheel much, so if you go out and thrash your stuff every weekend, you may get different results.

 

[VAhasnoWAVES]

it took me a minute to figure out how to read it... but here ya go:

http://www2.dana.com/pdf/J321-CV.PDF

 

[PoorManXj]

update...got it together and i forgot to add the length of the shaft bending at the double cardian so it ended up working....i cut the splines at 1 1/8 inches. Having it spinning doesnt guarantee a straight cut, i used to thick of a cutting disk i beleive thats why, so anyone reading this keep that in mind. The hole i drilled was just barley off center but just barley had to dremel the hole on the yoke just a tiny bit. when drilling i put my drill so if it jamed up it would just spinn the drill. Put the transmission in 1st-2nd to drill. Just make sure to kill engine before engaging to reverse or park. Took for a spin and no vibrations that i can feel. Was about an inch maybe more of plunger end of drive shaft that could compressed. Used lots of lube!!!! Thanks for the responses :smoker:

 

[PoorManXj]

it took me a minute to figure out how to read it... but here ya go:

http://www2.dana.com/pdf/J321-CV.PDF

thanks