Author: Mike

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Trail repair of Jeep Dana 30 Axle or U-joint

The Jeep Dana 30 axle will hold up under most conditions, but when you start adding larger tires and lockers as well as driving in more rugged terrain, there is always a chance something might break. Having the right tools and spare parts on board can save the day. A broken axle shaft or U-joint can be changed on the trail in about 20 minutes providing you are properly prepared.

Things you will need include; a jack, a spare shaft, a 13mm twelve point socket or wrench, a 36MM socket and something to turn it. You will also need the appropriate tools to remove your wheel and brake caliper. These vary from year to year and depending on your accessories. A hammer and a spare set of hub bolts will be helpful as well.

If your wheels have open centers, begin by removing the cotter key and the center nut on the axle shaft. This nut is very tight when tightened to specs. You will need either an impact wrench if you have on-board air or a long handled pull bar on the socket. If you have a closed center wheel, you will have to remove the wheel and have someone hold the brake while you loosen the nut.

Support the vehicle and remove the wheel. Remove the brake caliper and support it on the control arm. Try not to let it hang by the hose. Next, remove the brake rotor.

Using a 13mm 12 point socket, remove the three bolts that hold the bearing to the knuckle. The bearing will likely be stuck in the knuckle. My favorite way of removing it is to screw in some disposable bolts that have the same thread and hammer on the bolt heads. Once you hit the bolt head with a hammer, you will not be able to put a wrench on them in the future. I carry a set of bolts for this purpose in my axle repair kit.

If you don’t have spare bolts, you can still tap the bearing out using a hammer and pry bar. Try not to hit on the wheel mounting flange however as this can damage the bearing.

Slip the bearing out and then remove the broken shaft. If part of the shaft remains in the axle housing, use a magnet to remove it. If you can not pull it out with a magnet, you can also remove both shafts and push it out with a stick or long metal rod.

If you have jacked up the side you are working on high enough, you will not spill any axle grease. Even with it level, there should only be a small loss.

Slip in the spare shaft and check for any other damage. Put the bearing back in place and secure the three bolts. Place the rotor back on the hub and secure the brake caliper. Mount the wheel then tighten the center axle nut. Replace the retainer clip and cotter key.

Pump the brake pedal a couple of times to remove any slop that may have been introduced by removing the caliper before attempting to move the Jeep. Now get back to wheeling!
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Automatic wheel balance

Balancing tires

I have dealt with many different ways to balance tires since I started mounting my own tires several years ago. I have had very good results using a simple bubble balancer and lead weights clamped to the rims.

I have considered purchasing a spin balance machine on several occasions but the cost of the machine has deterred me considering the small number of wheels I balance in a year. I can pay to have several tires balanced for the cost of a machine. Also, for most tires my bubble balancer provides acceptable results.

I have studied various methods of automatic wheel balancing for years as well. As the tire wears, the balance changes. And short of taking the tire off the Jeep and rebalancing it, there is nothing else that can be done using the clam on wheel weight method.

I have looked at the rings full of mercury that bolt on the back of the wheel. I have studied the sand and ceramic dust methods used on semi trailer tires. However the simplest method for me to implement would be to add a liquid to the tire.

Looking at the mathematical proof of the physics behind the sand method, I theorized that any fluid would do the same. The material tends to move to the light spot as centripetal force takes over automatically balancing the tire as it rotates.

This week I came across the idea test subject. In the past I was fighting other vibrations at the same time such as bad bearings or U joints. This time however, my truck was running smooth and I had a tire with a big chuck of rubber missing.

Running the tire with no weights produced a huge bounce that could be felt at speeds over 40mph. The Jeep was un drivable at over 60MPH.

The first test was to balance it with conventional lead weights in the bubble balancer. It took slightly over 280 grams of lead on the rim to balance the tire. It was difficult to get that much lead on the wheel and on the test run one of the weights came off. However it did produce a smooth ride.

The next test was to replace the lead with a liquid. I did not want to use water as in freezing conditions it would make a block of ice in the low part and create a huge imbalance. I chose instead a 50/50 mix of antifreeze and water.

I popped the bead on the tire and poured in 290 grams of the balancing liquid. I remounted the tier and took it for a test run.

The initial test run showed a nice smooth ride. I was not able to exceed 60MPH on the test run due to road and traffic conditions but the ride was noticeable smoother than with the lead weights.

I plan to further test the liquid wheel balancing method to see if it will automatically balance all wheels. The math shows that it will work with tires that have dynamic balance problems as well. I can’t deal with these on my bubble balancer so if the liquid method of automatic wheel balancing works, I will not ever have to buy a balancing machine.
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Jeep Cherokee Factory Service Manuals

Get Professional-Quality

When making repairs to the Jeep Cherokee the Factory Repair Manual is a valuable resource. I keep a copy in the shop for reference. I also keep a digital copy on my office computer so I can read up on a job before I begin.

http://www.greatlakesxj.com/tech.html

The Haynes Jeep Cherokee Manuals are also handy for some quick reference data like torque and clearance settings that can be hard to find quickly in the Jeep factory service manuals.

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Always Use New Valve Stems

Always Use New Valve Stems

When I mounted Scott’s tires a few months ago, I did not have any valve stems in stock and I did not want to make the trip into town to get some. The ones in the rims looked fine so I just left them in place.

Then last week, Scott had not one but two valve stems break off due to the rubber cracking.

Last night I swapped in new valve stems for him. I broke the bead on the front side and used a pair of diagonal cutters to cut out the old valve stems. I pressed new ones in place and aired his tires back up.

I put them on the balancer for a tune up of the balance while I had them off.
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Clutch Pedal Goes to the Floor – How to Fix in a Honda Passport or Isuzu Rodeo

Clutch Pedal Goes to the Floor – How to Fix in a Honda Passport or Isuzu Rodeo

If you have recently changed the clutch in a Honda Passport or an Isuzu Rodeo and had the clutch pedal suddenly go to the floor without disengaging the clutch, you have most likely had the quick release throw out bearing come loose from the clutch.

There is no simple fix as the transmission will have to be separated from the engine to access the clip. There is however a way to keep the problem from happening again.

These vehicles use a pull type throw out bearing, a type I was not familiar with until I saw it on a Honda Passport. All the others I have worked with before use the more common push type throw out bearing. In the push type, the throw out bearing is pressed against the fingers of the pressure plate to release the clutch.

With the pull type, the throw out bearing attaches to the fingers and pulls back as the clutch pedal is depressed. On some vehicles the bearing is attached to the plate at the factory and in others like the Isuzu and the Passport, the bearing is designed to clip in place during installation of the transmission to the engine.

There have been numerous reports of aftermarket clutches having weak clips and they will come off unexpectedly often within days of installation. Since it is a relatively time consuming job to remove and replace the transmission, I preferred to have a more secure fixing of the bearing to the pressure plate.

Because the Isuzu bell housing has two large access holes, it is possible to attach the release fork to the bearing even if it is already attached to the pressure plate. Therefore the snap ring can be permanently fixed to the plate prior to installation.

I snapped the bearing into place and carefully put a few small welds on the clip to prevent it from ever coming back out. While this makes reassembly of the transmission slightly more complicated it is better than having to deal with it popping out unexpectedly.

I had to slightly modify my clutch alignment tool to make it fit through the bearing hole. I put it in my lathe and turned down the knurled part until it fit through the hole.

Reinstallation is the same as usual except that the bearing ears need to be aligned with the prongs of the release fork as the transmission is slid into the clutch disk. I used a long screw drive to manipulate the bearing through the two accesses ports on the bell housing. Once the forks engaged the bearing, I slid it up and proceeded with the normal installation.

I learned this trick from a Youtube video by briansmobile1. I was pleasantly surprised at how easy it was to engage the release fork with the bearing permanently attached to the pressure plate. The owner of the Passport was very happy that she did not have to buy a new clutch assembly to get her Passport drivable again.
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