Long Arm Kit Applicability

Hello all,

So I am new to the forums, but definitely not new to vehicles. I have come to a question in which I cannot find an answer to online, nor from the suppliers providing the product.

The vehicle:
I picked up an '85 cherokee with a 2.8L, a A904, and an NP207. Yes I understand that this is not the most attractive drivetrain in the world, but I need it running and capable by KOH since it will be a chase rig for our TJ that is racing. Trans and Tcase were rebuilt already for parts cost, $400, and the engine is in the process of getting a freshening up and all harnesses removed to run a straight carb. The vehicle is destined for an LS1 swap in the future so I am not concerned about powertrain right now.

So my question is as follows:
All of the LA kits that I have found online show '84-'01 model year applicability, but they list only the AX15/AW4 for trans and 231/242 for Transfer cases. I have called the manufacturers directly to ask if the LA kit will fit my jeep's powertrain or not, but no one knows for sure if they will fit or not.

I have my eyes set on the TNT kit or the Clayton kit, but TNT claims that it won't fit and Clayton says he isn't sure but is willing to work with me to get measurements and such.

I know that there was a small body change in '87 to fit the 4.0L, but I can't find any numbers or data that implies that the crossmember location may have changed.

So.......I ask the XJ knowledge base in hopes of getting an answer: Will any LA kit fit regardless of the applicability that the mfr lists? The crossmembers are the same and the trans mounts are also the same. Sooooooo what gives????!!!

If the crossmembers are truely the same and the holes are the same, then it's a definate maybe. I know there are multiple holes in the frame rails for moving the crossmember fore-aft. Since clayton and tnt want their frameside mounts in a specific spot, you may be out of luck, or you may have to do minor modifications to make it fit. The easiest thing to do is maybe take some measurements against a 4.0/AW4 jeep to see. Both these kits replace the crossmember. Stock AW4 crossmember front edge is about 14" back from the back of the lower control arm frame mount.

Thanks for the input! I will take some measurements and post up my results. I have to think that I cannot be the only guy ever to ask this question and I searched high and low for answer to no avail!

This is just me thinking off the top of my head on a late night, but in theory, since the lower arms are adjustable, as long as I don't bottom them out in length then I could technically adjust them to length as necessary. This of course is assuming that the axle mount to crossmember length is longer than the length of the arm joints end-to-end adjusted all the way down. right?

Don't count on that 2.8 being reliable for KOH...
Also, I thought koh was a no chase race anyways?

for proper geometry and probably liability... i think most manufacturers will tell you to mount the crossmember where they tell you to per their directions. this ensures that the axle can properly be aligned as well. now, if your willing to fabricate, then you can honestly put it where ever you want. that may involve adding frame rail stiffeners so you can give the crossmember a really good mounting surface. but id suspect that if your crossember is different, then proper fitment will be difficult, as most/all bolt on kits use these to locate the crossmember. now... you also have a not so common motor and trans... if your crossmember bolts in like later years, the easiest thing to do may be too look into an adjustable/universal trans mount like something offered from novak adapters to make your trans work with a companies crossmember because the issue may not be that your crossmember mounts to the frame differently, but rather, that the trans mount for your trans might not work with the long arm crossmember.

A stocker will work as a "Chase" Vehicle for KOH as all you are doing is driving between pits. There's no on course chasing.

Sorry, I can't provide any helpful advice concerning the 2.8.

I am really pleased with the Clayton kit on my RHD XJ. It's been on the Jeep seven years now and I would certainly buy Clayton again for my next Jeep. It helps if the XJ is not rusty to start with. I originally intended to fit the kit to a '93 but I decided it was much better to start with a low mileage 2001 to maximise the number of useful years for my investment.

If the support truck has to be used on the same terrain as the TJ, have you considered building a support truck that has many parts in common with it? There is a significant advantage to be had if the spares that you carry will work for both vehicles. If you are really desperate for a part the support truck can be cannibalised to keep the competition vehicle racing. Eg. tyres on wheels, starter motor, axle shafts or even complete axles, transmission and engine.

Think of the parts that are likely to fail on the TJ. If they are too big to lug about as spares, then build the support truck with them.

markw said:

A stocker will work as a "Chase" Vehicle for KOH as all you are doing is driving between pits. There's no on course chasing.

Click to expand...

He means to say pit to pit vehicle by day, and play rig at night!

I was thinking about this and I would try to find a cheap/free stock crossmemebr from an aw4 or ax15 (pretty much free from people going to a LA kit) and see if it will or is close to bolting up. If yes then I would think any kit would work.

IT is not the same, the arms are shorter. They accidentally sent me the V6 kit from rough country and the arms were too short, the crossmember was the same, just the arms were about 3 inches too short

bluejeepkid said:

Don't count on that 2.8 being reliable for KOH...
Also, I thought koh was a no chase race anyways?

Click to expand...

Why do you say that it won't be reliable? In its stock form, I would definitely agree. This thing is getting rebuilt by me with a standard carburetor. I am pulling all electronics and it will literally have like 4 connections to make it run.

I said chase rig, but its really gonna be just a vehicle we pile a whole bunch of crap and spare parts into to station at the pits and something I can go get into trouble with at night.

VAhasnoWAVES said:

for proper geometry and probably liability... i think most manufacturers will tell you to mount the crossmember where they tell you to per their directions. this ensures that the axle can properly be aligned as well. now, if your willing to fabricate, then you can honestly put it where ever you want. that may involve adding frame rail stiffeners so you can give the crossmember a really good mounting surface. but id suspect that if your crossember is different, then proper fitment will be difficult, as most/all bolt on kits use these to locate the crossmember. now... you also have a not so common motor and trans... if your crossmember bolts in like later years, the easiest thing to do may be too look into an adjustable/universal trans mount like something offered from novak adapters to make your trans work with a companies crossmember because the issue may not be that your crossmember mounts to the frame differently, but rather, that the trans mount for your trans might not work with the long arm crossmember.

Click to expand...

You bring up a good point. I hadn't thought about a universal type of trans mount. I am like 65% confident that my crossmember mounts similarly to how an AW4 crossmember from later years mounts, but I want to make sure before I pull the trigger on a $1k kit that I will need to do heavy modifications to.

markw said:

A stocker will work as a "Chase" Vehicle for KOH as all you are doing is driving between pits. There's no on course chasing.

Click to expand...

I said chase rig, but its really gonna be just a vehicle we pile a whole bunch of crap and spare parts into to station at the pits and something I can go get into trouble with at night.

Vince said:

Sorry, I can't provide any helpful advice concerning the 2.8.

I am really pleased with the Clayton kit on my RHD XJ. It's been on the Jeep seven years now and I would certainly buy Clayton again for my next Jeep. It helps if the XJ is not rusty to start with. I originally intended to fit the kit to a '93 but I decided it was much better to start with a low mileage 2001 to maximise the number of useful years for my investment.

If the support truck has to be used on the same terrain as the TJ, have you considered building a support truck that has many parts in common with it? There is a significant advantage to be had if the spares that you carry will work for both vehicles. If you are really desperate for a part the support truck can be cannibalised to keep the competition vehicle racing. Eg. tyres on wheels, starter motor, axle shafts or even complete axles, transmission and engine.

Think of the parts that are likely to fail on the TJ. If they are too big to lug about as spares, then build the support truck with them.

Click to expand...

Thanks for the input.

whitexj98 said:

He means to say pit to pit vehicle by day, and play rig at night!

I was thinking about this and I would try to find a cheap/free stock crossmemebr from an aw4 or ax15 (pretty much free from people going to a LA kit) and see if it will or is close to bolting up. If yes then I would think any kit would work.

Click to expand...

Thanks pete. I think I am gonna hit up a Jyard today and try to take some measurements of an AW4 and compare to mine.

unhitched said:

IT is not the same, the arms are shorter. They accidentally sent me the V6 kit from rough country and the arms were too short, the crossmember was the same, just the arms were about 3 inches too short

Click to expand...

Thanks for the input, but the kits that I am looking into don't specify engine. They only specify trans and Tcase and I am not looking to go with a rough country kit.

Depending on how much you have in the rebuild of the 2.8. I would consider a a JY replacement "bolt-in" 3,4L

I understand you did not mention RC, but they definitely have 2 different sets of arms, one for the V6 and one for everything else... I would assume that other vendors either have 2 arms they offer, or it only fits certain motor combos

Go with the polyperformance long arm.

Does not rely on the crossmember, so it really shouldn't matter what drivetrain.

And it is hands down the best long arm kit for XJs.