Category: Car repair

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Installing Air Shocks on a Jeep Cherokee

Installing Air Shocks on a Jeep Cherokee

I have been running the Gabriel Hijacker air shocks on the rear of my Jeep Cherokee for 15 years or so. But the bags have developed leaks and no longer stay aired up. I searched for replacements but I could not find a replacement listing for the High Jackers for my Jeep. I did however find a listing for the Monroe Air Adjustable shocks.

I got my set through Amazon, although Advance Auto carries them as well. They are sold as a set of two so don’t get confused when ordering.

The Monroe shacks came with all the air lines and fittings needed to install them. There were also some extra bolts in the box that are not used on the Cherokee. I guess these shocks are also used in other applications.

The toughest part of changing the rear shocks on a Cherokee is removing the upper bolts. These are little 8mm bolts with 13mm heads. They are exposed to road salt and are in a hidden pocket in the unibody. So they are easy to break. I always begin by tightening them just a bit. This seems to help break the corrosion bond. Then I carefully work them out. I use a 3/8 ratchet with lots of extensions so I can get a good feel of how the bolt is turning. If it sticks, I run it back in a bit.

You can help loosen the corrosion by spraying something like PB Blaster or Liquid wrench into the space above the bolt. It is difficult to get to the actual bolt however.

If, you do break a bolt, there are several ways to fix it. You can drill through and put a nut on top or weld on a bar pin eliminator made out of an old sway bar bracket.

I was able to get all four of my bolts out intact. I then removed the lower 18mm nut and slipped the old shocks off the pins. I removed the old air lines from the High Jackers.

The Monroe shocks seemed a tad shorter than the Gabriel shocks and I had to lift the axle just a bit to make them reach. I started the top bolts first and then set the bottom on the pin. I put bolted up both shocks before attaching the air lines.

The new shocks came with a complete air line kit. I elected to retain my old air lines however. At first I had trouble getting the lines to seal at the shocks. After a couple of tries I noticed that the installation kit had O rings in it. Once I installed the O rings the old lines sealed just fine in the new shocks.

The air shocks give me adjustability and just enough lift to help keep it off the bump stops. It also helps to adjust for the trailer tongue weight as well.

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Converting from 4wd to 2wd temporarily

Converting from 4wd to 2wd temporarily

I have found several temporarily convert a Jeep Cherokee to 2wd. Some times it is chasing a noise or vibration. Other times it is working around a damaged part. In this most recent case, it is waiting for proper gears to arrive to complete a re-gearing. Whatever your reason, here is the procedure I used.

First remove the front drive shaft. Depending on your reason for converting to 2wd, this may be all you have to do.

If you need to concern yourself with the rotating assembly, either obtain some 2wd stub shafts or some normal outer shafts. If you have broken a U joint on the trail you probably have an outer shaft with the ears broken that you can use. I used the 2wd stubs shafts from the ZJ I just scrapped. I keep them in my trail spares just in case.

Remove the hubs and replace the axle shafts with the stub shafts. Be sure to torque the 36mm nut to 175 ft lobs to set the bearing preload properly. Reinstall the hubs and brake assembly.

In this most recent case, the carrier is out of the diff. So I put on the cover and stuffed some rags in the pinion end and tapped in an old seal to keep most of the trash out.

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Scrapping the ZJ

Scrapping the ZJ

There has been a burned out ZJ sitting in front of my barn for over a year now. I finally decided it was time to let it go.

The rear disk brakes are on my off road XJ. The engine (what we bought it for) is in Jenny XJ. The rear axle was sold to go in another ZJ. The transmission was sold for yet another.

It seems a shame to trash so many good parts, but there has been little interest in the body parts I have offered for sale. I have stripped off as much as I thought I might be able to sell and yesterday I loaded the rest on the trailer.

It is fun trying to load a Jeep with no rear axle on the trailer. I began by jacking up the rear and running my steel ramps as far as I could under the body. I then lowered the body on the ramps. I left the front axle in place with tires so that at least that end can roll.

I then set up my XJ at a right angle to the trailer and fastened my snatch block to the front of the trailer. I threaded the cable through the block and attached it top the rear of the ZJ. There are several holes in the rear bumper so it makes a nice place to adjust the angle of the pull by selecting different holes.

I used my battery charger to keep the battery up on my Jeep during the winching process. I then pulled the ZJ up the ramps.

Once on the wooden trailer floor, I put a floor jack under the bumper. This made the back roll as well as helped keep parts that were hanging down from dragging.

I slowly pulled the ZJ up onto the trailer. I often had to wait for the battery to recover before making another pull. Since the steering box has been removed, I used a long steel bar to turn the front wheels to line them up with the ramp.

Occasionally the whole trailer would slide toward the winch dragging the rear of the XJ it was attached to along with it. As more weight came on to the trailer, this became less of a problem.

It took an hour or so of maneuvering to finally get it in position on the trailer. Now I can strip the front axle and steering. Then it will be off to the scrap yard unless someone lets me know really quickly that they need a door fender or hood.

Update: pulled the front axle on the trailer. After the control arms and shocks were unbolted, the only thing holding it was the swap bar end links. I cut those with the torch and the axle rolled right out.

Update 2: I was waiting at the gate at Buff Salvage this morning when they opened at 8am. I was greeted by the friendly scale operator who helped fill out the form for a car with no title and sent me on my way to the track hoe. The excavator operator used hid giant thumb ot easily lift the ZJ off the trailer and drop it on a pile of other cars including what looked like a pretty nice Nissan ZX. The then used the bucket to squish the ZJ flat. He then noticed the axle that was left on the trailer and after a couple of missed grabs was able to pluck it off the trailer as well.

The return trip across the scales gave me a weight ticket which I took to the pretty girl at the cashiers window. She traded me a check for my paperwork. It was a quick and easy process.

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Re gearing the Dana 30

Re gearing the Dana 30 – aborted

I had planned to install 4.10 gears in Jenny’s XJ this weekend. I removed the wheels, brake calipers, rotors and pulled the hubs and axles out enough to get the carrier out.

I then removed the cover and the carrier. I did not need to spread the case at all. It slipped right out indicating that the bearings were pretty worn.

Next I removed the pinion and the associated parts. As I was driving out the races from the housing, I noticed there was an oil baffle under the inner pinion race. I found no way to save it while driving out the race. I carefully marked all the parts so I would know where they went back.

I did not have the right sized punch to knock out the roll pin that holds the cross shaft in place. After some experimenting, I found an old drill but that worked. I then found that the pin would not come out with erring gear installed. So, I removed the ring gear. A few light taps with a hammer caused it to pop off the carrier.

Next, I removed the spider gears and shims to transfer to the new carrier. Since the 3.55 gears use a different carrier from the 4.10 gears, she had to replace the carrier. I found driving the pin in to the carrier and keeping the spider gears aligned to be difficult. In fact I damaged one of the spider gear shims the first time I installed the pin and had to get a replacement.

Once the spider gears were in place, I prepared to install the ring gear. I set the carrier in the freezer and the ring gear in the oven. I heated it to 200 degrees while I had a Coke and a sandwich.

I then set the warm gear on the cool carrier and it slipped right on. I put in a couple of bolts to make sure it was lined up correctly.

I was then got ready to put the bearings on the pinion. When I unwrapped the pinion from the black plastic, I suddenly noticed it looked different. It had different landings for the bearings. I then noticed it was longer. I started making comparisons and then realized there was no way this pinion was going to work in the housing.

I then laid the old ring gear beside the new one and saw the obvious different slant of the gears. She had been sold the wrong rotation gear set. XJs and a few Wranglers use Reverse cut gears in a high pinion Dana 30. Most Wranglers, ZJs and Fords use the standard cut low pinion Dana 30.

So, her Jeep sits on the lift waiting for her to get the proper cut gears and bearing set so we can finish up. We also have to find a source for the oil baffle since it looks like I will destroy one for each trial of the pinion depth shims. I have decide that the Dana engineers have worked overtime to design the most annoying way to set up a differential. Maybe it will not be that bad once I get the hang of it.

Update: After getting miss delivered and lost for a week, I finally go t the right set of gears for the install. I sat all the a parts out on the floor to make sure I had all I needed.

I mounted the new ring gear on the new carrier. I applied the lock tite from the kit and tightened the new bolts to 55 ft lbs. I removed the old bearings from the old carrier and retrieved the shims from under them.

I made some set up bearings by opening up the inner race of some used bearings I had. Not the ones that came off the old carrier because those seemed really worn. I then put the shims under the set up bearings and slipped them in place.

I used my bearing separator to pull the old pinion bearing to retrieve the slinger under it. The slinger bent some as the bearing separator was tightened up but it sprang back flat once it was off the pinion.

I slipped the slinger on the new pinion. I then heated up the new bearing with my hot air gun and slipped it onto the pinion as well.

I measured the shim pack under the race and prepared a new set of shims to account for the difference in marked pinion depth and for the oil baffle.

I will use a .020 shim in place of the baffle for the trial fits and then install the baffle once I have the right shim pack picked out.

Now, I am ready to have the Jeep back on the lift to complete the installation.

Update: The regear is now complete: See Dana 30 Gears

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Replacing the Rear Drive Shaft in a Jeep Cherokee

Replacing the Rear Drive Shaft in a Jeep Cherokee

After installing a Slip Yoke Eliminator kit in her NP231 transfer case, Jenny needed a different drive shaft in the rear of her Jeep Cherokee. The SYE requires a CV shaft like the one used in the front of the Cherokee. In fact, with her set up, a front shaft actually fit.

However the front drive shaft was at its fullest extension to connect up in the rear. So, if there was any pay at all in the splines, the drive shaft would vibrate. Finding a used shaft in good enough condition to run smooth was proving to be a challenge. Also the added abuse from off road driving made the choice of a stock front shaft no so good in the rear.

After much research, she decided to try a custom made shaft from Adam’s Drive Shaft. She also liked their skull themed logo.

There was no measuring involved. She simply sent them the specs of her Jeep along with the Pay Pal payment. A few days later the shaft arrived.

To remove the old shaft, I removed the four bolts at the rear diff and the four at the transfer case. These all use 8mm hex heads. I have found that the Craftsman 8mm hex wrench is the only one in my tool box that fits the bolts properly. My local Sears store rarely stocks these however. I bought Jenny one and made it into a necklace for her to take when she goes off road.

The Adam’s shaft is much heavier than the stock shaft indicating that it is made form stronger material. It was also just a tad longer. I did not measure it, I just set it in place and tested that it fit perfectly.

I elected not to use the 12 point bolts they sent since I have standardized on the six pint bolts. I will at a later time swap to the twelve pint bolts on both ends so that it will be easier to find a wrench that fits.

With the bolts tight, I took it for a short test run. It seems to turn freely and smoothly. I will have to wait until I can get it up to speed to evaluate the balance. I saw a couple of small weights welded to the shaft so I expect it to run smooth.

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