cross member issues on tj

[jimsh]

ok, ill have to explain a little, recently bought this tj which was in need of some tlc let me be frank, the guy who had it before me doesn\'t know what preventative maint. is. I think things only got looked at if they didn\'t work at all. So in the 6 months i have had the vehicle ive replace rear brakes , rear wheel bearings  ball joints, hubs  drums  and had sensor issues with a nasty exhaust leak on the header at the collector. welded it up once and its back, Not the major issue , i have a vibration at 60 + bad. Here\'s what i believe is the issue, the 6 crossmember bolts aren\'t securing the crossmember. Now this is my first jeep , use to drive fords, so i am ubsure if these are threaded into the frame or if there is actually a nut on the inside of the frame rail. At any rate what i think i am going to do is cut off the bolts and weld new  nuts on the outside of the frame rail and reattach crossmember.  That is unless some one has a better idea  Thanks in advance   Jim

[Wingman]

The factory put \'riv-nuts\' into the appropriate holes in the frame.  The riv-nuts will rust and either spin in place or pull out of the frame.  It is a very common issue.

My last fix/sell project had to have them all replaced.  If you can get the bolt out, you\'ll have to drill out or grind off what is left of the riv-nut to put another in.  My suggestion is work the bolts out very carefully by using an impact and turning out, then in, then out, until it yields.  You may be able to save the conical bolts and some drilling.  It\'s really so much fun, you\'ll cry... :banghead:

McMasters sells a 10 pack of riv-nuts for ~ $13.  Here is their link.  The dealer will charge big $$.

Don\'t forget to support the drivetrain and the crossmember!  It\'s heavy!

As far as the vibration, you\'ll have to be more specific and list any mods you have done that may have contributed.

ps. I have an extra factory header that might fit your application that\'s been re-welded, also a common issue.

[jimsh]

Thanks, ill be working on this next weekend, Wanted to wait until i installed my new lift because ill need to install transfer case drop kit but i cant wait, the vibration that im getting i believe is from a combination of things, tranny mount , this crossmember moving around, and possibly rear drive shaft out of balance. i believe the rear of the tranny is moving around at high speeed, 60 + im going to put a camera under the jeep today and verify this as long as my cam doesnt go flying off the underside of the jeep.

[CoraC143]

Erik had a good fix on his CJ crossmember. First he removed the stock bolts and crossmember, then cut and drilled a 1/4\" plate for each side of the frame with holes corresponding to the stock mounting holes. Next he drilled out the captured nuts on the inside of his frame. Then he welded grade 8 nuts to one side of the 1/4\" plate. Then welded the plate to the frame with the new captured nuts inserted into the frame in the freshly drilled holes.

The result, stronger frame and grade 8 nuts and bolts and the bolts can easily be replaced if needed or lost.

[jimsh]

i like this idea better, i don\'t have to wait for parts to come and i wont have this issue come up again.  At least not with the crossmember. Again thanks for the input

[Crusarius]

TJ is a fully boxed frame. it is a good idea on a CJ frame that is channel, but I don\'t think you can get it to work with fully boxed frame.

[ollllllo]

My CJ stock, is two pieces of channel welded together = fully boxed frame.

[MrMindless]

not all CJs were fully boxed (Smike\'s was open C) but that\'s neither here nor there....

[jimsh]

Again thank you i think i am going with this , im going to cut off all the bolts and drill existing holes big enough so that new grade 8 nut will slide into holes, cut 1/4 \" L plate and drill holes for new bolt, weld nuts on inside of L and weld L onto frame  i understand if my welded nuts break loose i am in the same boat only worse but it a chance im willing to take, Again thanks for your input , this will def be  a stronger fix than just welding some nuts to the bottom of the frame. I figure ill use l instead of a straight piece so i can weld the top of the L on the outside of the frame and the bottom of the L on the bottom of the frame. Seems like a good repair to me  and once again thanks for your advice, cant wait to meet and wheel with you guys. i will be at wp on june 19th with wny off road and ill try to make the june m & g up in rochester  

[jimsh]

Well i went to dodge to order some of the conical bolts because they are sort of essential, The price has gone down, bolts now only 4.80 ea. but you will get a laugh out of this the can not get me the correct size nutcert  they recommend  a new frame because nutcerts according to them are unservicable, 3,300 for  a new frame. lmas That being said i will be cutting into it this sat and welding up my fix, is this going to give me issues in december when i need a new inspection? As of right now it is my daily driver and you will obviously be able to see the new angle iron welded onto the frame. Looks like im going back to cali in july, one of my customers has a new project going on and wants to fly me out to oversee construction. I may look into a cheap tj with motor and tranny issues so i can bring back a good frame and tub but it all depends on funds. Once again you guys have been great with the advice it is really appreciated. btw conical bolt in at dodge tommarow so im a go for sat to tear it apart, hope the weather holds, as my shop is the driveway in the back yard.  

[gCracker]

I don\'t think you would have any inspection issues(unless you get a very picky inspector), but weld the angle on the inboard side of the rail so it is not as noticeable.  Why not use normal nuts and bolts?

[Wingman]

I think it uses the cone shape to locate the plate and hold the bolt more securely.  Wouldn\'t want that thing coming off at speed.  A regular bolt with loc-tite should work though.

As an alternative, would acorn-style lug nuts work for the cone portion?  Thread them onto a fine thread bolt and then into the frame nut you welded in/on?  Maybe grind them down so they aren\'t so tall before threading them onto the bolt?

Depending on how rusty things are down there, you may be able to pry on the skid while turning them out.  I had a couple come out that way and saved the bolt.

$.02

[MrMindless]

I would not expect nor endure or stand for any inspection issues from this fix.

[jimsh]

I was of the same mindset, the setup i intend is going to be much stronger than factory but as this is my second year in ny i am not really sure what they look for. I brought a 87 chevy g20 van with me from cali and the sob at the inspection shop was going to fail it because the reverse lights werent coming on. On the way here the heater core went out in ok. last jan. so i stopped and bought an inverter and a electric heater, quick fix, any way to keep a long story short it started blowing fuses the fuse that operates the back up lights used to attempt to get heat and I forgot to replace it.
The shop charged me like 9.00 to change the fuse or he was going to fail it.  Even tough he said it was the cleanest van of its age he has seen since like 1990. So i am kind of leary of the inspection process here.

[ollllllo]

honestly it depends on the shop you take it to.
I took my 85 CJ7 to \"a friends, brothers shop\" here in Victor last year for NYS Inspection. They almost failed it because I removed my CAT. The law was being interpreted a few different ways by both the shop owner and the mechanic performing the inspection. In the end, the shop owner reluctantly passed the jeep, but said he wont do it again. It seems to me that NYS is getting harder on the shops and the Inspectors, in turn they are busting balls to cover their butts.

Look on the bright side, at least you didnt have to buy a catalytic converter.
 :stuck: