Wut.
With the rear driveshaft out, and the Jeep in 4 hi, it should have no problem driving. If it's not moving and the tires aren't resting on a frictionless plane, something else is wonky (like t case isn't getting into gear).
I read that as “front tires don’t pull hard enough to recreate it the vibe” not that they didn’t pull at all.
That is what I meant, yes. Sorry for not being clear! When I tried to do it, my front tires spun in place before moving me.
Another thing to consider is the health of the u joints.
As for the U-joints, I believe I replaced them about 5k – 10k miles ago? When I got the Jeep, it was about ~120k miles on it, and as of now I'm just shy of 150k. So, they shouldn't be that old yet. Now, as for the
quality of the installation, that might be a different question. I'm very new to Jeeps/cars/trucks, let alone mechanical work in general, so I've been learning as I go. From what I can tell, they seem to be fine, no play or leaking or anything when I checked them.
I had that shuddering vibration under load for years at 2-2.5” suspension lift. Didn’t cause any premature wear of components that I could tell. Eventually moved on to bigger lift and SYE. Smooth as glass. Now I have the same shudder on another 2” rig. I’m not worried about it.
This is what everyone around me is telling me to do, just ignore/stop worrying. I'm pretty confident that it's been like this since I installed the lift about 2 years ago, but I'm just paranoid. I recently had my front U-joints on the front driveshaft explode on the freeway, but I'm pretty sure it was due to a bad U-ball joint that I hammered in too tight.
Keep in mind that drivetrain vibrations are usually caused by the u-joints themselves vibrating/shaking from working into an excessive angle. That type of vibration can't just be lived with as it can take out the u-joints and possibly the adjacent seals on the axle and tcase too.
I agree with this, not that you need my agreement, ha.
But, putting up with vibes will rattle critical components, cause leaks and who knows what
This is where my main concern lies. It's gotten to the point where I am checking to make sure that my driveshafts are on the right way; I even turned it around because of the vibrations at 70mph that I had. When I test drove it, I think it was better, but to be honest, I'm not quite sure what I should be feeling/looking for. At this point, every shake, shudder, or vibration I feel down the road I wonder if it is a result of the driveshaft.
That’s true, just not what the OP is experiencing. “Lasts a second.” A second. How many seconds does he drive? A second of vibration at heavy torque starts is a very tiny portion of the time he drives, and the wearability will correspond.
Correct. The only time I ever feel it is: if I let off the gas when getting onto my driveway and then accelerate up it slowly (I can try to get a video if not clear), on a heavy acceleration, as in an impatient jump off the line, or foot to the floor. I would think most would say: “Just don't do that” which they are probably right, but I am a dumb 23 year old who likes to pretend my Jeep can get off the line fast to then been dusted my friend's Corolla.
Honestly I'm not totally sold that, that is the issue as it is at a hard start only. Driveline alignment vibration issues usually happen at a higher drivshaft rpm (different rpm range for everyone depending on setup) but not usually launching from a stopped position. I would do as others have said and use washer to test it first dropping the T-case. I have a feeling you might find it to be something else. Since TJ's don't have leafspring suspension you should have no axle wrap and if you do then that's the first problem to repair. I would also examine your U-joints, T-case mounts and trany mounts and even motor mounts (even if they are aftermarket mounts the have replaced the OEM mounts). I would also look at the OEM slip yoke housing as these have been known to wear over time and can cause a vibration. If the last item is the case then I would move forward with an SYE or SSYE. I personally prefer the Teraflex SSYE it is cost effective and an easy install.
What would I be looking for with axle wrap? I'll double-check the motor mounts, and I just replaced the transfer case mount with a Mopar one from Rock Auto, but I will double check it. As for the transmission mounts, aren't they the same as the transfer case one, or does it have its own set of them?
When you say slip yoke housing, do you mean for the axle, transfer case, or both? What should I look for? I'm not sold on the SSYE as I don't plan on going any higher than I am now, so I don't think I would need it. Unless at this height, it has a major advantage over the regular SYE.
I believe the OP noted in a past post that he installed a UCF skid plate. This was not listed in the build data. I do not know how much that raises the transfer case, but that would increase the drive line angle.
Depends which skid he installed...UCF makes three different heights
You guys are always catching me slacking!
Here is the skid-plate I purchased. I don't think it changes the drive line at all. The reason I got it was due to the front driveshaft rubbing on the transmission skid plate thing in the at certain articulations.
I know I say it in every post I make, but I really want to thank you guys for all the input and advice. Like I said, I'm still really new to all this, and this forum has not disappointed me with a lack of help/information. At times, it's almost an information overload for someone like me. I'll head to Home Depot to get everything to diagnose.