IRO SYE vibes!!!

[keep0njeepin0n]

Edit: oops... misreadhttp://www.stu-offroad.com/axle/pinion/pinion-1.htm

You said the same thing, just with different wording. And from what I'm being told, NO, the pinion angle should sit a little lower than the driveshaft to account for axle wrap.

 

[georger]

Ok, update!!!! All vibes are gone at WOT and low speeds, now I get slight constant vibes at 60+ with steady throttle applied. If I let off the gas, it goes away. So, I'm thinking, maybe installing a 1 degree shim?? I don't know if the vibes increase or go away above 65, as I have not been able to safely achieve that speed without getting in trouble!

I am going through the exact same frustration as you with the IRO H'n'T. I've had the DS balanced twice, replaced all U-joints and the centering ball, added 4° then 6° shims, the vibe remains (completely smooth with the rear DS out). With my 6° shim, the pinion points directly at my DS.

Maybe I missed this, but how does your DS line up with the pinion with the shims removed?

 

[robsjeepxj]

Are you sure you cut the output shaft perfectly flat and the center bolt is torqued to spec, did you use locktite on the bolts? The slightest amount of angle on the cut can cause vibs under load especially heavy acceleration. H&T's are junk, a real SYE would have been a much better, stronger chose.

 

[RCP Phx]

Thats one of the problems when using that style yoke.It is a slip yoke(by its original design and intended use) and doesn't have a "press" fit

 

[georger]

Are you sure you cut the output shaft perfectly flat and the center bolt is torqued to spec, did you use locktite on the bolts? The slightest amount of angle on the cut can cause vibs under load especially heavy acceleration. H&T's are junk, a real SYE would have been a much better, stronger chose.

It's flat, but perfect? I'll double check that and clean it up if possible. Thanks for the input.

 

[XJRN]

Are you sure you cut the output shaft perfectly flat and the center bolt is torqued to spec, did you use locktite on the bolts? The slightest amount of angle on the cut can cause vibs under load especially heavy acceleration. H&T's are junk, a real SYE would have been a much better, stronger chose.

The IRO one bottoms out at the bottom of the shaft if you cut enough of the shaft off so even if the cut is not straight it should sit on it anyways. If you cut while the shaft is spinning it comes out straight as well.

 

[Darky]

Are you sure you cut the output shaft perfectly flat and the center bolt is torqued to spec, did you use locktite on the bolts? The slightest amount of angle on the cut can cause vibs under load especially heavy acceleration. H&T's are junk, a real SYE would have been a much better, stronger chose.

Pretty happy with my RE hack and tap. Jeeperjohn cut it nice and square and hasn't been a single vibe (from the drivetrain) since.

 

[kastein]

I don't see why a properly done H&T is "junk". The only real difference is the way the yoke is held on and the large washer + grade 8 bolt seems fine to me, it's not like there is much tension on a driveshaft with a slip joint in it.

The best way to cut the shaft, as stated above, is to put the vehicle in 2wd, set the parking brake, remove the rear shaft, shift into reverse, and cut with an angle grinder while the shaft spins. If you have a 95 or earlier, install the seal and plate first unless you want to take a bath in ATF...

 

[georger]

Thanks for the tip guys, it wasn't that far off flat, maybe 1/16". Checked it with a square after grinding while rotating. Vibe is still there though. I'm going to see if I put it back together out of phase when I put the new u-joints in. Then take it somewhere else to check balance on the ds if that doesn't work.