97 TJ frame stretch to LJ
- Thread starter myjeep3
- Start date
10" after the door, and 5 at the end? will I have to remove the rear cross member or just add 5" after it, or cut off at the cross member, add 5" build new gas tank support, then reweld the crossmember?
I would image if we were to just add 15 after the door, and leave the rear as is would require extending the brake lines?
Mike_H is correct, a TJ6 is not the same as an LJ. A TJ6 is the same as a 5" rear stretch on an LJ. It you are looking to drop an LJ tub on a stretched TJ frame you'll need to do the 10" before and 5" after the axle. As far as the details, you'll need to measure to get things right. The body mounts are a little different and other details will need to be looked at. It shouldn't be too hard but that depends on your skill level.
If you want to simply extend 15" in front of the axle then you'll need to extend brake lines and fuel line, cut the tub a bit, and get a new driveshaft.
If you want to simply extend 15" in front of the axle then you'll need to extend brake lines and fuel line, cut the tub a bit, and get a new driveshaft.
I would imagine you need to move the rear cross member. If you add 15” after the door, your wheels won’t line up with the wheel well
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I do not want to cut the tub, and would like to use the LJ brake, and fuel lines.
For the rear section, would it be easier to just leave that crossmember there and add 5" after it?
You're not going to have all the answers until you start cutting. Sorry, I just can't answer how easy or not easy something will be. Personally, I would look at an LJ and try to figure out where the length was added and duplicate that. I think just adding material after the cross member will look terrible, plus, I think your fuel tank will interfere.
You can make the 97 frame work, you won't like how much work it is.
Skid plate nutserts are in the wrong place.
It will have to be extended before the rear wheel arch and then after the rear wheel arch.
The steering box mount sleeves are different, not hard to fix, but has to be dealt with.
3 frame side body mounts under the doors are good to go.
To put the gas tank in the same place as it is now, you need to add a crossmember which is to modify your current one and then add the bumper crossmember to the part you add after the wheel arch. Or move the bumper one back and add the intermediate one. Moving the bumper one back is an issue due to different frame bends behind the wheel arch.
TJ-6 is what they call a TJ frame that has been extended 15" before the rear wheel arch to retain the same relationship the standard TJ rear wheel opening in the tub has to the frame arch for the rear axle. Then the tub is extended the exact same amount so you can use a TJ Unlimited hard or soft top and the stock rear half of the longer cage. The wheelbase winds up at 108". Basically you cut a TJ right behind the doors through the frame and tub and move that back 15" to use the stock top and cage back half from a TJ Unlimited.
You are getting completely hung up on the small stuff that becomes very evident after you dive into the project. If you have both the 97 frame and the one that needs a frame, get them close to each other and get out your measuring device. The brake lines, fuel pump harness, brake cables etc. are easily solved and dealt with.
But, the only way to reuse what you have is to put everything in the same location on the 97 frame. You have a blueprint under the rig now, use it.
What if I retain the tj steering box and skid plate, the tj is complete, so I can reuse whatever that is needed.
I could cut the tj frame before the rear control arm, extend 10", put the LJ tub on, and extend the rear as needed base on where the lj tub sets.??
Personally I would try to find a good LJ frame and sell your TJ frame. It sounds like a lot of time, work and money to make what you have fit.
I agree but No fun and satisfaction in doing that. These toys need to be moded to satisfaction..
It is all able to be done. Mix and match whatever you need to in order to make it work, just know that some of the mixing and matching is more work than it needs to be. If you retain the early steering gear, you'll need the matching steering shaft off of the TJ.
I don't know that the number is exactly 10". I would find that number by measuring from the center skid bolt on a 03-06 TJ to some feature on the frame that gives me that number.
If I was going to attempt this, I would level the frame front to rear and then from the center skid bolt center, go straight back to a line squared down from the hole at the apex of the rear wheel arch. That will give you the exact amount you need to move the arch.
Yes, I could extend the tj frame, drop the lj tub on it, and resuse the steering gear, shaft and skip plate. Move the fuel and brake lines etc of the lj etc.
The tj already has a lift, dana 30/35 geared at 4.88 with 35".
For the measurements, you are saying to line up the front of both frame and measure back? Do the skid plates have the same dimensions?
Left end of arrow is center of the middle skid bolt on an 03-06 TJ frame or TJ Unlimited frame. The line is a plumb line down from the hole on to very top peak of the rear frame arch on a frame that has been made level or you have a very long straight edge parallel exactly to the frame.
Get that distance on the two frames in question and that will give you the exact amount of extension needed.
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