Hog Rush

2000 XJ
3" Rusty HD lift
BFG 235/75/15

Hi, I had some driveline vibes above 55mph and narrowed it down to the transmission mount. I had been driving the jeep to work 60 mile round trip for about a month.

I picked up a daystar Tranny mount and Brown Dog Rubber Motor mounts.
It seems the motor mounts are ok under power braking so I will get to them later.

I pulled the transfer case cross member down and found a broke off bolt to the frame. Was rusted so it had been like that for a while. It has a 1" case drop kit and the bolts appear to be non hardened bolts. Silver tin coated with "8.8" embossed on them.

Did not have access to my ease outs so I went back with it so I could get it home. When going back, on the same side, the other bolt would not tighten up and appears to be stripped.

Is there a bolt on strengthening kit for this?
The bolt is fine, the threaded frame boss is stripped.

I thought about drilling and tapping to a bigger bolt but am not sure if the boss is thick enough.

Thanks

Hog Rush

Anyone?

DFlintstone

Weekends can be slow. Without being familiar with it (Yet)(my tranny mount is bad), I'd guess you could drill'n tap. And yea, time to find an easy out I suppose. Sorry btw,,,that sucks!

cpefy3

If there is enough meat still on the bolt I would cut off the head of the bolt with an angle grinder and pull it out with stud puller.
https://www.google.com/shopping/prod...d=0CNwBEKYrMAU

This would allow you to still use the existing threads. If this is not possible, I would cut off the rest of the bolt, and then drill and tap it with the next size bigger. Make sure you buy a quality tap. I tried using a cheap harbor freight tap and made my life hell, once I switched to a good quality tap took me 20 minutes. I have never had good luck using an easy out, that is why I didn't suggest this, but this is just my personal opinion. Good luck.

93gc40

8.8 IS a hardened bolt.

If the hidden nuts and stud in the frame are bad... You will probably have to cut access holes so you can fix.

Whiplash

oem bolts are 10mm, you could try drilling/tapping up to a 12mm or 1/2" if you wanna get away from the metric stuff. I just did my cross member and was able to work out one broken stud, but the other took a shyt on me. I was able to drill out with a 3/8 bit and still had enough meat to bolt in. Added a good dose of loctite for "hope this works" sake

Hog Rush

Since I started this thread I have researched it a bit further.

It seems the factory uses Rivet Nuts or nutserts in the uniframe. They are tac welded in place.

The one broken off can be fixed with an ease out as it seems. The other bolt is not stripped. The nut sert weld broke loose and is spinning in the frame.

I saw where one guy took the seats out, drilled from the bottom thru the top of the frame into the cabin, and was able to drop a bolt down thru there to the bottom. Then tac welded the bolt to the bottom of the frame to leave a stud there to put a nut on.

Then another guy just bought 1/2" nutsert and replaced it.

Both will require some time to fix. I like the bolt idea.

ajk0204

Thanks for researching this. I have the same problem and have been scratching my head for a week!

Whiplash

OR you could save pulling the seats and drilling into the cabin and use a wire to pull the bolt thru the frame and down into the "nut free" hole. There's a pretty large hole up forward of the unused "nutsert" ahead of the cross member. It's what i did for my rear shocks. Punched the broken bolts and used a 14ga wire held onto a bolt/washer with electrical tape and drew it thru the subframe and down thru the open hole

Hog Rush

I thought of that but not sure the extra long bolts required for the transfer case drop would be able to flip over in the hole without the tops hitting the upper frame.

Whiplash

hears ya Hog Rush.... time for an SYE???

good luck in whatever route you decide to go.

Hog Rush

I ordered the RE Hack N Tap yesterday.

Should I go back to std transfer case height?

Hog Rush

Well, I finally got around to focusing on the Jeep again.

I drilled down through the floor with a 1 1/4" hole saw over the holes for the transfer case cross member. I also popped out the existing thread rivets where the old bolts screwed into.

Then I installed 1/2" x 2" bolts in their place with nyloc nuts. I will do the other side as well when I get time.

I used spray foam and aluminum roof tape to seal the holes. Then covered it with the carpet.

Before, I had driveline vibes. Now, after the stripped bolt fix and the new tranny mount, it is like a new Jeep. I got the solid no rubber tranny mount. So when idling, I get a little dash vibration. But it just reminds me I am in a Jeep.

Stabsthedrama

Wait....did you verifiably track down the 55mph vibe to the trans mount?

That's a part I never thought of....

I'll be yanking out the front ds this weekend to test that, but other than that I'm literally down to LCA's and wheels/tires at this point (leaning towards tires, but I wanna kill them before swapping them, no use wasting them since they got a lot of meat still)

But I get a bad vibe still at exactly 55, and have literally replaced EVERYTHING wobble related other than LCA's, front ds u joints, and tires (wheels have been rotated and balanced, but I still suspect highly its the tires) - never even considered the trans mount....

hmm....might have to try that myself as well....

XJlimitedx99

Only problem with this is there is no way to get a wrench on that bolt. The shocks are super easy to access after you punch them out but these bolts are not.

To the OP, I was going to suggest you don't drill holes in your floor because that's what I did about a month ago and I wasn't super happy doing it. It worked though. I broke 3 of the 4 bolts. One of my buddies cut a hole into the bottom of the frame rail (around his broken bolt) and welded a new nut up in there. It was much more professional (and easier) than drilling.