On-Island XJ Build

[ROKTAXI]

Your build reminds me of the '94 I had: LOTS of upgrades... 241 TC, Warn axles front / back, rear disc brakes, 5" lift on 33's / Detroit Tru Trac up front / D44 rear with Detroit Locker / 5.38's. However, I had an overheating issue I couldn't resolve and ended up selling it and getting an '05 Liberty CRD. So far so good.... except for a vibration issue.

It has a 242 TC. Removed the rear driveshaft after exhausting all other attempts thinking it was some rotating mass up front. After removing it, the vib went away. The guy that diagnosed it also mentioned that the driveline angle was more than he liked. Unfortunately, it's not an easy fix with having independent rear (coils) suspension. So I don't know how to resolve the driveline angle without eliminating / reducing my 2 1/2" lift. Still no guarantee that that is my issue.....

 

[Mitch502]

Your build reminds me of the '94 I had: LOTS of upgrades... 241 TC, Warn axles front / back, rear disc brakes, 5" lift on 33's / Detroit Tru Trac up front / D44 rear with Detroit Locker / 5.38's. However, I had an overheating issue I couldn't resolve and ended up selling it and getting an '05 Liberty CRD. So far so good.... except for a vibration issue.

It has a 242 TC. Removed the rear driveshaft after exhausting all other attempts thinking it was some rotating mass up front. After removing it, the vib went away. The guy that diagnosed it also mentioned that the driveline angle was more than he liked. Unfortunately, it's not an easy fix with having independent rear (coils) suspension. So I don't know how to resolve the driveline angle without eliminating / reducing my 2 1/2" lift. Still no guarantee that that is my issue.....

Is a SYE not an option?

 

[ROKTAXI]

Unfortunately, the 242 that's in a Liberty is different than the standard model Jeep. I'm told the SYE has to be custom built. I checked with Tom Woods Driveshafts. Didn't get a price yet as I'm still not sure it's the problem. One guy I found out had the same issue and turned out to be in the rear diff. I was either carrier bearings / Trac Loc cluches / wheel bearings. He replaced them all and the vib went away but doesn't know which one was the culprit.

I've sunk MANY hundreds of $$ chasing this and hope to find a more definitive answer or at least narrow it down a little more.

 

[Mitch502]

Unfortunately, the 242 that's in a Liberty is different than the standard model Jeep. I'm told the SYE has to be custom built. I checked with Tom Woods Driveshafts. Didn't get a price yet as I'm still not sure it's the problem. One guy I found out had the same issue and turned out to be in the rear diff. I was either carrier bearings / Trac Loc cluches / wheel bearings. He replaced them all and the vib went away but doesn't know which one was the culprit.

I've sunk MANY hundreds of $$ chasing this and hope to find a more definitive answer or at least narrow it down a little more.

A hack n tap is out of the question?

 

[ROKTAXI]

....and what might that be??

 

[Mitch502]

https://www.ironrockoffroad.com/product/hack-n-tap-slip-yoke-eliminator-kit.html

 

[ROKTAXI]

Thanks for the link! I was also looking at a YouTube DIY of the process = https://www.youtube.com/watch?v=pG-d13ikmcc Pretty slick. I need to do this no matter what. The OEM thing is not wonderful. I'm surprised that my 4x4 shop didn't know about this.

I just have to figure out if in fact that is my problem or if it's in the diff / wheel bearings.

The vib is only present at 40 - 47 mph at any RPM, any gear and ONLY under throttle pressure. Vib is gone in the coast cycle.

 

[Mod7x]

Try dropping the transfer case mount 1". My xj had a similar vibration after I put a 2" lift in, I dropped the t case 1" and no more vibe, I made my own drop kit but they are pretty cheap to buy.
Looks good by the way.

 

[Whaler]

Thanks Mod7x and Mitch502, ROKTAXI

I'm taking the jeep off-island this weekend for the first time in a long time and will log 200+ highway miles. I'll be listening to the drive-line closely. What's interesting is that I only notice the vibration/rumble immediately after I let off the throttle, and it only lasts for a second or two. It seems like there's no vibration at all when the driveshaft is under power but letting off the gas creates slack for a moment until it settles down. It's also not very loud or noticeable. The fact that the vibration is intermittent and brief makes me feel somewhat comfortable about proceeding with this trip. Going to try and do the headlight harness and bulb upgrade some night this week before I go.

 

[Ray Hyland]

How did the long highway trip go?

I really like the way you have done this Jeep. It looks classy. Well done

 

[Whaler]

Thanks Ray, I really appreciate that! I'm trying to keep it simple, clean and robust. The trip went well, no issues. The drive-line vibration was still there but I notice it less. I can't say if it's improved or I'm just getting used to it.

One takeaway: the XJ is loud at speed. Living on a small island, I never get it up to highway speed so this trip was a reminder that it's definitely more "tin can" than "cocoon," although I mean that in the most affectionate way possible. Recently my vinyl door handle wraps started coming loose, so I've taken the driver's-side door apart and plan to install some Dynamat while I'm in there to test whether or not I like it. Anyhow have thoughts on Dynamat? I don't like the idea of adding unnecessary weight, but I do like the prospect of a quieter cab on long trips.

This is what I need to fix:

 

[GordoSmasho]

I fixed mine by getting new door cards. Haha
Mine were a bit harder to find being a 2dr but some fell in my lap and i traded my old ones to a buddy so he could build half doors with them. Are you going to try and repair them?

 

[Whaler]

Hey Gordo, yes, I'm going to try and fix it. The entire interior door card (panel?) is sold as one part and it's strikes me as too wasteful to scrap the whole thing over a little piece of vinyl. You lucked out with a good trade. The arm rest is attached to the panel with what look like plastic hot rivets from the factory, which I can't replace.


I broke the rivet heads off with a chisel and then drilled out the center of each rivet, freeing the armrest from the rest of the panel. You can see intact and broken rivets below:


I have it disassembled and plan to glue the vinyl to the armrest before reinstalling it. The vinyl has a integral foam backing, so I hope the foam itself is strong enough to hold up because I believe the vinyl edge was originally "pinched" between the door panel and armrest, which kept the vinyl in place. I'm not sure I'll be able to secure it as tightly the second time around, so the glue needs to bond the foam to the armrest plastic really well. I'll let you know how it goes.


I was considering wrapping a new piece of leather around the whole armrest and stitching it, but my buddy talked me out of that over-complication. I'll fall back on that if plan A's adhesive fails.

 

[JSwanson]

Take a look or just replace your trans mount if you haven't already. I replaced mine and it was the culprit for most of my vibration. Reasonably cheap and pretty easy to do. As far as dynamat goes I used peal and seal from lowes its a poor mans version and works great for me. Some complain of a tar smell but I never had a problem. My whole roof is done and patches of it in my doors as well. Someday my floor will be done with it too. https://m.lowes.com/pd/Peel-Seal-In...s-6-in-x-25-ft-Aluminum-Roll-Flashing/1018733 just a suggestion. Great job so far.

 

[Whaler]

Dynamat scraps installed inside the door cavity already seem to make a difference when the door closes.

Thanks JSwanson! I’ll take a look at the transmission mount.