Grinding into reverse

[Lumpy Grits]

THX for the up date. So many times we never hear the outcome.
With the new clutch. Watch your pedal freeplay as the clutch breaks in. You want 1-1 1/4".
Good luck,
LG

 

[b3uhbp]

Hey guys, now that the new clutch is in I'm noticing a minor vibration. Its only there when the drive train is engaged. I.e. when my foot is on the clutch it goes away. My first thought was u-joint but I checked them and replaced one. What I noticed was there was a dent in the drive shaft and when I set it on a flat surface I noticed that it's not perfectly clocked. Instead of sitting flat it rocks slightly. Question is, how much would the clock have to be off to cause the vibration? I think I'm feeling it now when I didn't before due to a new, polyurethane Transmission mount. The old one was rubber and totally shot. What say you all?

 

[Lumpy Grits]

Any 'off' will lead to bad 'vibes'.
Can you correct the phase, buy re-indexing the slip spline?
If there's a dent as you say-The shaft may well be bent.
LG

 

[Hedgehog]

You can clock the drive shaft, if necessary you can change universal joints, about all other driveshaft work needs to be done at a Transmission shop. Just to be clear, your driveshaft needs professional attention.

 

[b3uhbp]

You can clock the drive shaft, if necessary you can change universal joints, about all other driveshaft work needs to be done at a Transmission shop. Just to be clear, your driveshaft needs professional attention.

So I take it that clocking the shaft is NOT something I can do?

 

[Lumpy Grits]

I'm think'n his shaft may be twisted.
One reason I had mine made from .250 wall tubing, after I twisted mine up.
Both have lots of 'rock-rash' on'em now with no issues at all.
LG

 

[Lumpy Grits]

So I take it that clocking the shaft is NOT something I can do?

Did your remove the slip-spline when you R&R'd the u-joint? You may have reinstalled it 'off' a spline or so. Easy to do the miss alignment thing, and have done such myownself.
LG

 

[b3uhbp]

Did your remove the slip-spline when you R&R'd the u-joint? You may have reinstalled it 'off' a spline or so. Easy to do the miss alignment thing, and have done such myownself.
LG

No. I removed the whole drive shaft to avoid any such issues. Y'all have any thoughts on my theory that I'm feeling the vibration now due to the new poly tranny mount. It,s stiffer and might transfer more vibration.

 

[Lumpy Grits]

I run the poly mount also, it's the only t'mount that has held up. I feel that you found the issue with the out of phase u-joints and the damage to the shaft. With the rear DS out. Lock the front in and take it for a drive. Do you still feel any 'vibes'?
Pull the shaft, put it on the flattest item you have (kitchen counter)and lay a level perpendicular to the shaft, on the front and rear u-joint yokes. If the bubble position is not the same on both, you have found the issue......
Do you also run the torque arm and snubber on your mount?
LG

 

[b3uhbp]

I run the poly mount also, it's the only t'mount that has held up. I feel that you found the issue with the out of phase u-joints and the damage to the shaft. With the rear DS out. Lock the front in and take it for a drive. Do you still feel any 'vibes'?
Pull the shaft, put it on the flattest item you have (kitchen counter)and lay a level perpendicular to the shaft, on the front and rear u-joint yokes. If the bubble position is not the same on both, you have found the issue......
Do you also run the torque arm and snubber on your mount?
LG

Pulling the rear shaft is a good idea. I'll try it. I will certainly check with a level as well. I did place the shaft on a flat surface when I had it out which is how I discovered the slight wobble, maybe a 1/32 to 1/16". I have a twin stick Dana 300 . Not sure it will go into front wheel high. Need a little speed to feel an vibration. Yes on the torque arm and stud.

 

[Lumpy Grits]

There's no reason why the D/300 should not work here.
Select 'HI' & 4WD.
LG

 

[b3uhbp]

There's no reason why the D/300 should not work here.
Select 'HI' & 4WD.
LG

You're right. Yes, I was confused. Got it to work okay though it was hard to get it out of 4WD high. Now just need to try it without the rear shaft.

 

[Lumpy Grits]

Sometimes it helps if the jeep is moving at no more than walking speed to 'work' the levers.
Other times, you may need to back up 5-10 feet to remove the torque bind when both shafts are in.
LG

 

[Hedgehog]

Lumpy -
remember, you had him remove the drive shaft. Without that moving is a pushing affair.

 

[Hedgehog]

"So I take it that clocking the shaft is NOT something I can do?"

No, I wrote:

"Originally Posted by Hedgehog
You can clock the drive shaft, if necessary you can change universal joints, about all other driveshaft work needs to be done at a Transmission shop. Just to be clear, your driveshaft needs professional attention."

 

[Lumpy Grits]

Lumpy -
remember, you had him remove the drive shaft. Without that moving is a pushing affair.

Doesn't the OP have a front DS in place?
LG

 

[Hedgehog]

True but moving it to get the front to unbind will be difficult with one drive shaft removed and the other out of gear....... The whole idea of moving the vehicle to engage the front driveline and moving it to disengage without a means to mechanically move the vehicle made me and go "hmmmm". I do support the idea though. Test the vehicle with the offending part removed. Something else that might make the vehicle shimmy and shake, how long has the vehicle sat in one spot? Some tires take a flat spot rather easily. Just a thought.

 

[Lumpy Grits]

The movement helps with gear engagement/alignment for shifting.
Trick I learned when driving heavy equipment, many years ago.
Flat spoted tires, is a very good thought!
LG

 

[Hedgehog]

Absolutely correct. The fun part about rebuilding things like transmissions and transfer cases you get to see why the binding happens. The front and rear output shafts are very similar in a Transfer Case . There is a gear that slides on some very robust splines. on one direction the outer gear engages another gear in the manner we can all imagine gears to mesh or engage. The little stinker is o the other end of the output shaft. The sliding gear slides along the splines going from engagement to neutral to another engagement, but this time its the splines that do most of the engagement are on the INSIDE, the output shaft spline aligning with the spline on another gear with the sliding gear s inner splines bridging the gap essentially welding the output shaft and the gear spline into one. Yes, confusing I know. Where I see improvement could have happened in the design is where the two splined meet. The splines are cut perfectly square, meeting with no real gap. It's mechanically beautiful. The problem is the two splines have to be perfectly lined up to engage. If there were a slight taper to the gear spline the engagement would catch and slide together far easier than it does. There, now that's clear as mud! So, yes motion, especially back and forth motion helps engage and disengage, a Transfer Case .

 

[hagar]

I believe not having the flywheel resurfaced was a mistake.
You stated that it saved you time and money.
$30 to $40 to have this done is ALWAYS worth my time and money.
Any good mechanic should know that.
So be it.
Time will tell.