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Anyone that has driven their TJ down a rocky trail should agree that the lower shock mounts on the rear axle do in fact stink! They hang down and are great at grabbing rocks and such. During Thanksgiving, 2002, I was unfortunate enough to land on the passenger side lower mount and collapse it. OK....so, when you break something, you can either fix it or you can upgrade it. I spoke with Blaine, my buddy in California, about the shock mounts. Blaine had helped me with my rear disc conversion and I had seen a couple of his rear shock relocations on some friend's TJs....so it seems like one heck of an opportunity to upgrade rather than merely replace. We set a date, a few months down the road, to coincide with a local CA rock crawling event. I would watch a friend compete on Saturday and we would wrench on Sunday. As it turned out, the LA area received some 50 year record breaking rain during the weekend I was there. The rock crawling event was cut short on account of the rain but Blaine's garage was high and dry so Sunday's "event" turned out much better than did Saturday's.
Let me start by saying that this mod is much more fabrication than it is bolt on. Where as the rear disc conversion that Blaine helped me with was mostly a swap out of TJ stock parts for ZJ stock parts, this is not quite the case for relocating the rear shocks. Blaine does great fab work. If you don't, I would NOT recommend your jumping into this modification without the assistance of someone who is comfortable around this kind of project. The average Jeeper is most likely not up to doing this by themselves. If you are average, do yourself a favor and find a competent person to assist you in this project. In other words, consider this fair warning as to the difficulty of this project.
NOTE: I have been asked to add another warning.... DO NOT MELT YOUR GAS TANK WHEN YOU DO THIS MOD! A person that did this mod asked me to tell you that you need to be careful as to how much heat can be transferred from the hot frame to the nearby plastic tank. So, considered this fair warning, a second time, as to the potential difficulty of this project.
As I said, Blaine does great fab work. Of course, I already knew this, which is why I was willing to let him cut a couple of sections out of my frame. Part way through the morning, he had to go into the house to make a phone call. As he was leaving the garage, he asked me, "Do you know how to use a cutting torch?". I replied, "No". He paused for a second and then said, "Well, then I don't think you should play with the plasma cutter". He smiled and went into the house. I sat in the garage and waited for him to come back out....needless to say, I didn't play with the plasma cutter. The last thing I needed was to ask Blaine if he might be able to weld my frame back together! Enough chit chat....time to get to the modifications.
Let's run down the parts we used in doing this modification.
Here is the part number of the shock tower we used. If I remember correctly, Blaine said it was from a pickup truck. You will need two of these (one for each side). Cost is in the $20 each range.
Here is a picture of the full shock tower. The lower
portion (right hand side) will be cut off once the proper length is determined.
I'm sorry that I can't just tell you how long to make it. It depends on
your spring ride height, your bump stops, and your axle droop. All three must be
taken into consideration when determining where (and thus how long) the upper
mount is to be located on the TJ's frame.
You will need a lower shock mount. Blaine had some 5/8" shock pins left over from some previous work. These shock mounting pins were used for a Chevy 1 ton application. Note also that there is a high collar lock washer on the above shock pin. The bushing was just a tiny bit thick for this mounting pin so Blaine slipped the lock washer on the pin to act as a small spacer. The same affect could have been had by cutting a thin slice of tubing and using it as a spacer.
The shock eyes in the Rancho shocks we used were too large for
the above 5/8" mounting pins. As delivered, the bushing hole on the shocks
were too large and allowed the shock to flop around on it. You must
remember that the shocks being mounted were not intended for a TJ application.
You will want to pick up a pair of 5/8" shock eye bushings for the bottom of the
shocks so that it will fit properly on the mounting pin. These are made by
Cut the end of the existing bushing eye off and push it out of the shock loop. Lube the new bushing with some polyurethane grease and carefully press it into position using a bench vise. Sometimes the bushing won't align correctly so take your time and you should be able to get it.
The shocks we used were the Rancho RS-9000 series adjustable shock. I've been running this type of shock since going to my 6" lift. I ended up with the newer version that has the 9 position adjuster since the old 5 position model is being phased out. I picked up a pair of RS-9005 shocks and brought them with me to Blaine's house. He had the previously mentioned parts waiting for me when I got there.
Please note that not all Rancho shocks have the same size shock eye. As such, your shock (selected because of its correct length for your application) may not need the bushings and it may even come with shock pins (some RS-9000 shocks do). The 9005 shocks we used required new bushings in order to fit what we were using for mounting hardware. Your situation will most likely vary. This is all part of the fabrication part of this project, getting the pieces and parts to all fit together to provide you with a great Jeep modification.
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