Mike – Page 66 – The Jeep Guru

March 21, 2011March 21, 2011

Jeep Cherokees Off Road at Golden Mountain

Jeep Cherokee Off Road at Golden Mountain

This weekend, Jenny and I met up with some of her Facebook friends at Golden Mountain Off Road Park in Sparta Tn. We took along our two Jeep Cherokees both with three inch lifts and 33 inch tires.

I normally trailer my Jeep, but in an effort to save fuel, I decided to drive the 100 miles to the park. Jenny’s is her daily driver so she drives it every where she goes anyway. The lack of carpet, sound deadening and a muffler made it impossible to hear my cell phone.

I was pretty tired by the time we made it to the park. However, I got my energy back as we pulled off our doors and aired down the tires and disconnected Jenny’s sway bar. Mine is long gone and makes for a wiggly ride on the road.

We son met up with Andy, Jimmy and Ben. They all had much larger tires and lifts than us so they let up lead the way.

We headed up trial one on the left side of the park. Often this trail which is marked as easy is very slick, but it was dry enough for us to handle this day. We made the turn onto trail 10 and enjoyed the step descent and then the climb back up to the top of Bounty Hill. The descent was much easier this trip because the little tree that was in the way of the proper line down the rocks is now gone.

We met the other guys back at the top of the hill and sat for a while and talked while the kids played.

Next we decided to run the inner loop on trail 12. We started off making the climb on trial 11. This is fun rocky climb. It seemed a bit tougher this trip than before however as the heavy rains had washed out some of the smaller rocks. We all made it up with only a few back ups.

We hit 12 and made our way around. The others stopped to play on the rock climbs of trail 38. We were not able to finish the loop however due to a tree across the trail. We turned around and met back up with the others. We then parked for lunch and watched a group of buggies climb the hill. We got to watch a flop right off. They flipped him back on his wheels quickly and he continued the climb.

Next we made our way over to trail 14 and made the loop. We got a bit confused on the multiple trails there and ended up coming back out the way we went in instead of making the circle indicated on the map. This was probably the most technical trail we ran al day. It took about 30 minutes to get both our rigs through about 100 yards of rocks. Jenny’s tie rod got a bit tweaked in the process, and she put some scrapes on her new skid plate. I got to test my new diff cover as well.

After that we ran trail two and Jenny had a run up part of trail 16. We parked for a while at the pavilion and enjoyed the scenic views before heading back down.

We went in by the picnic shelter and down trail 11. It is always fun to go in that was as it does not look like a trail until you actually drop off the ridge behind the shelter. We took trail two back to the parking area and put our doors back on. We said good bye to our new friends and headed south.

We found an air compressor just a few miles down the road and aired up our tires. I was pretty tired by the time I got home. But it was a good tired. Off roading is a great stress reliever.

March 15, 2011March 16, 2011

Dana 35 Pinion Bearing Replacement

Janice’s Jeep was making a roaring noise from the rear end. After just a short test drive, the pinion on her Dana 35 was much warmer than the rest of the axle. Listening with a stethoscope confirmed that the pinion bearing was noisy.

I tried just changing the outer bearing and seal but since the race was worn was well, I had to disassemble the differential and change both the pinion bearings.

I ordered a Pinion bearing kit from Crown Automotive. This kit came with bearings, a new crush sleeve, shims and a reusable gasket.

I removed the wheels, and brake drums. Then I removed the cover and drained the fluid. Next I removed the carrier. I was careful to keep the bearing races and shims in the proper order. I noticed that the bearing caps were marked with and X to keep them on the correct sides. One X was vertical and one was on its side.

I dropped the drive shaft and removed the pinion nut. I used a dead blow hammer to knock the pinion out of the front bearing. I then used a pry bar to remove the pinion seal.

I used a chisel to tap out the two bearing races. I used a soft punch to drive the in the new bearing races. I used a bearing separator and hydraulic press to remove the inner bearing from the pinion. I ended up breaking the bearing race while pulling it off, so I was glad I was not trying to reuse it. I reused the shim under the bearing. I used my heat gun to warm the bearing and then slipped it onto the pinion shaft.

I installed the new crush sleeve on the pinion as well. Next, I cooled the pinion in the freezer for a while before slipping it in to the housing and placing a warmed outer bearing on the shaft.

I installed the seal and yoke and then tightened the pinion nut until the preload on the bearing was about 15 inch pounds. To check the preload, I had to use several adapters to get from the ¼ inch drive of my torque wrench to the ½ inch drive of the socket.

With the preload set, I reinstalled the carrier. I used a dead blow hammer to tap the bearings into place. I reinstalled the caps making sure they were turned the right way round and they were on the correct sides.

I slipper the axle shafts back in place and re secured the C clips. I then reinstalled the center pin set screw.

I put the cover back in place using the reusable gasket from the kit. I put some silicone on the cover to glue the gasket to it and cleaned the housing well. I put the bolts back in and tightened them evenly. I filled the housing with gear oil and the Limited Slip friction modifier compound.

I reinstalled the brake drums and wheels before taking it for a test drive. It was much quieter and the pinion did not heat up as before.

The pinion bearings are also available from Advance Auto:

March 14, 2011March 14, 2011

Jeep Dana 35 Wheel Bearing

A few weeks ago I replaced the wheel bearing and seal on Janice’s Jeep Cherokee. Her Jeep has a Dana 35 rear axle with anti lock brakes and the Trac Loc limited slip.

Not long after, the rear was making a roaring noise worse than before. I noticed a lot of heat in the pinion after a short drive so I replaced the pinion bearings.

I also replaced the axle shaft due to some checking in the bearing race area. I used a ZJ shaft as a replacement. This meant that I had to swap the anti lock tone rings as they are different. I used an acetylene torch to heat the ring and allow it to fall off the shaft. To reinstall, I used my electric heat gun to warm the ring and then tapped it into place with a hammer.

The noise continued to grow and there was noticeable sloppiness in the brakes. This was followed a few days later by a leak in the wheel bearing seal.

I pulled the wheel and brake drum to inspect and found that the new bearing was extremely worn. There was noticeable slop in the axle and the brake drum had been dragging causing a lot of heat.

I pulled the cover, removed the C clip and pulled the axle. The axle looked fine. I extracted the bearing and found it very worn. I installed a new bearing and seal.

Upon closer inspection of the bearing, I noticed that the race was cracked. I suspect that I got it twisted while installing it in the axle tube. I had used a punch to install the bearing since I did not have the correct size bearing driver available at the time.

This time I turned down one of the bearing driver I have using my mini lathe to make it fit. The bearing went in with a satisfying thunk. Hopefully this one will last.
[phpbay]Jeep wheel bearing, 10[/phpbay]

March 14, 2011March 14, 2011

Jeep Front Wheel Bearing Hubs

The noise in Jennifer Jeep was traced to a wheel bearing hub. The bearings are not normally serviceable. The whole hub is replaced as a unit.

To swap the hub, begin by removing the wheel and tire. Her 33” Dick Cepeks are very heavy.

Next, remove the brake caliper and rotor. There are two bolts holding the caliper in place. The old AMC Jeeps use a 7mm hex key while the Mopar built Jeeps use a standard 13mm bolt. For some odd reason, one side on Jennifer’s Jeep has 12mm head on the bolts.

Remove the cotter key and the keeper. Then using a 36MM socket, remove the center nut. An impact wrench works great for this. If you are using a breaker bar and need a way to keep the wheel from turning, you can remount a wheel with the center cap removed and use the weight of the vehicle to hold the shaft.

Remove the three bolts that hold the hub to the knuckle. These have 12 point 13mm heads. If the hub is stuck in the knuckle as it often is, I have three sacrificial bolts that have the same thread. I screw them into the hub and use a hammer on the bolt heads to drive the hub out of the knuckle. Do not hit the wheel mounting flange as this will damage the bearings.

Slip the hub and brake shield off the knuckle. You can leave the axle shaft in the axle to prevent loss of gear oil.

To replace; slip the new hub into the brake shield and then into the knuckle. If your Jeep is only for off road use, you may choose to delete the brake shield as it tends to catch rocks and debris and does not help cooling at low speed.

Tighten the hub to knuckle bolts. Place the washer and nut on the end of the axle shaft and torque to 170 foot pounds. I used a pry bar through the U joint to hold the axle while torquing it. It is possible to damage the seals on the U joint using this method, so be careful how you place the pry bar in the yoke if you choose to do it this way. The proper preload torque is important to making the bearings last. Replace the keeper and cotter key.

Mount the rotor and brake caliper. Be careful not to over torque the small brake caliper bolts after getting used to working with the larger bolts.

Remount the wheel and tire. Torque the lugs nuts and give it a test run. Jenny’s Jeep was much quieter after the bearing swap.
[phpbay]jeep wheel hub, 10[/phpbay]

March 11, 2011March 14, 2011

Jeep 8.25 Differential Cover

Jeep 8.25 Differential Cover by Blue Torch

A few years ago, I backed into a stump and dented my rear differential cover. I thought it was not a bad dent until I pulled the cover off for an oil change. That is when I saw the groove that the ring gear had cut in the cover. I hammered out the dent and reinstalled the cover for more wheeling. I began shopping for a stronger cover.

I found very few choices for a replacement cover for the 8.25.

I finally found the one I wanted at Blue Torch Fab Works. But I did not want to pay the $140 price. Later, they offered the same cover in a weld it your self kit. Jennifer also has an 8.25 and when she found she could buy two covers for less than the price of one, she got two under the condition that I weld up both of them.

I was not sure my welding skills were up to the task so I asked my Dad for advice. He suggested that I simply have him weld them. That sounded like an excellent plan; so I took him up on the offer.

While I mostly use a wire feed MIG, he prefers his stick welder. Our welder is an old Hobart with a four cylinder Continental flat head engine just like used in the Willys Jeeps. It had not been run in years. So, my first task was to get the old welder running.

Some cleaning on the distributor cap and a bit of ether in the carb and the old motor roared to life. This welder is really loud when it runs; but it welds really nice. Dad showed up with a hand full of rods and after we figured out how to assemble the pieces, he started welding. I did the finish grinding and touched up some spots with the wire feed. I used a flap disk on the grinder to make a very smooth finish on the welds.

Next, I filled them both with water and let them set to test for leaks. Finding none, I sanded them again and painted them with Rustoleum Red paint.

Several of the bolt holes have very little clearance between the weld fillet and the hole so I elected to use hex bit Allen head screws instated of the normal hex head. I got these at Fastenal.

I removed the old dented cover and drained the fluid. It looked a bit contaminated with water, so I discarded it. I cleaned the mounting surface. I applied an even coat of black RTV on the cover and installed it using the Allen head bolts. I tightened them in a crisscross fashion.

After letting it set a bit, I added fresh gear oil. The Blue Torch Cover uses a nice big screw in plug for the filler. The cover also holds quite a bit more fluid than the stock one. I think I put in almost three quarts. I then coated the threads of the plug with pipe sealant and screwed it in place. Since I did not have the right sized hex bit, I made a tool using a 3/8 bolt and a couple of nuts jammed together.

The Blue torch cover looks really nice and is very strong. I think the axle would break before this cover dents. I think it will add strength to the axle housing as well.