Regearing the Jeep 8.25

Regearing the Jeep 8.25
How to set back lash and pinon pre load on the Jeep 8.25

I recently put 4.10 gears in Jenny’s XJ. Her Jeep has a Chrysler 8.25 rear end. There seems to be very little info available on the 8.25 compared to what is on the web for the Dana 35 and Dana 44. So here is how I did it.

I began by removing the rear end from the Jeep and replacing it with our spare 8.25. That gave me the opportunity to take my time and not be in a rush to find parts. We got parts from our Crown Distributor as well as Advance Auto and Ebay.

With the axle out and mounted on my work stand, I removed the cover. Since this cover will be replaced with a Blue Torch Fabworks Kryptonite cover, I set the original aside.

Next, I disassembled her Lock Right locker so I could remove the axle shafts. The 8.25 uses the same length axle shafts on both sides so I did not have to keep track of where they went.

Next, I used a punch to mark the bearing caps so I could keep track of where they went. I could not see any factory marks like the Danas have. I removed the two small bolts that hold the keepers and then removed the keepers. I then removed the bearing cap bolts and the caps. I set all the parts in a box in order so that I could easily put them back where they came from.

Next, I slipped out the threaded preload plates and set them in the box. Then I was able to lift out the carrier.

I then rolled the axle over and drained all the oil out. I then removed the pinion nut and the yoke. I used a soft hammer to tap the pinion out. I then pried out the front seal.

I made a drift out of a piece of soft steel pipe and drove out the pinion bearing races. I set the races and crush sleeve aside to be replaced.

The gear set came from Ebay. It was slightly used but in perfect condition. The first odd thing I noticed about he 8.25 is that the bolts that hold the gear to the carrier are reversed threads. I was sure glad I read that before I tried to get one loose. They are marked with a big “L” on the heads as a reminder. I had to clamp the carrier in my vise to get them loose as they were very tight.

With all the bolts out, I used my heat gun to warm the ring and gently tapped it off with a soft hammer. I set the old ring gear aside to be sold.

Removing the carrier bearings was a bit of a challenge. I used a bearing separator and a two jaw puller to get them loose. I also warmed the bearing with the heat gun to help reduce the force needed. Due to the shape, I could not fit it in my press. I made a plug out of an old ball joint for the puller to press on while pulling the bearing off.

I installed the new bearings by warming them with the heat gun and chilling the carrier in ice water. I tapped them with my soft hammer to make sure they seated.

I chilled the carrier and warmed the new ring to slip it in place. I then snugged the bolts down to make sure it was seated properly.

Next, I removed the lower pinion bearing from the old gear set to retrieve the shim under it. I used the bearing separator in my press this time. I also had to heat the bearing with a torch to get it to release. With the shim retrieved, I set the old pinion aside and put the shim on the replacement pinion.

I then used my die grinder to open up the inner race of the pinion bearing until it slipped easily on the pinion shaft. This became my “set up bearing.”

I used my bearing driver set to press new races into the housing. I did chill the races in ice water before installing them. However, I did not attempt to heat the housing. There was a noticeable difference in the sound of the hammer on the driver when the races seated.

I assembled the new pinion with the old bearings and yoke but no crush sleeve or seal in to the housing and snugged the pinion nut just enough to take out any end play. I then set the carrier into place with the new bearings and races installed.

I fabricated a tool to turn the back lash adjusters using a nut from a Ford fan clutch, a length of ¾” pipe and an old ½ inch drive socket. I welded the nut to one end and the socket to the other end. The back lash adjusters are 36mm hex. A Dana 30 axle nut will work as well as any other 36mm nut. You can also use the miller tool C-4164.

I set the adjusters in place beside the bearings and set the caps on. I tightened them finger tight at first. I then used the tool to turn the adjusters to take out all the back lash but not put any extra pressure on the gear.

I made sure that all the end play was eliminated from the carrier bearings. I had to rotate the assembly a few times to get the bearings seated in the cones. I then set the back lash to about .003 inches using about 10 ft lbs of torque on the adjusters.

I then tightened the cap bolts to 70 ft lbs. I then tightened the right side adjuster to 75 ft lbs. or until I got a back lash of between .006 and .008 inches. I then checked the left side and found it to be close to 75 ft lbs as well.

I then coated the ring gear teeth with yellow marking compound. I rotated the assembly to get a gear wipe pattern. I was very happy when the pattern showed the pinion depth to be correct since the shim I had from the old gear was the only one I had. The Timken rebuild kit we got did not come with pinion shims.

Since I was happy with the pattern, I removed the carrier and pinion. If I had needed to change shims, I would have slipped off the set up bearing and tried a new shim using the same procedure.

Next, I installed the new pinion bearing by heating it and pressing it on the pinion shaft. I then installed the new crush sleeve, outer bearing, seal and yoke using the new nut from the kit.

I repeated the back lash adjustment procedure to get a back lash of .006 inches with the adjusters at 75 ft lbs. I rechecked the torque on the ring gear to carrier bolts. I then compressed the crush sleeve to get a pre load of 20 inch pounds. I noticed that then nut turned a long way with no change in preload and then suddenly the preload went up as I made the last 1/8 of a turn on the nut.

The torque needed to compress the crush sleeve was significant. I had to use a long breaker bar to turn the nut and a large pipe wrench to hold the yoke. With the preload and back lash set, I installed the keepers on the adjuster plates.

Since the adjuster tool had made numerous trips across the axle seals, I replaced them before installing the axle shafts. I reinstalled the Lock Right locker and secured the axles with the c clips.

I then put a bead of RTV on the gasket surface and installed the new Differential cover. I tightened the bolts finger tight and then let the RTV set up. I then tightened them the rest of the way down.

I waited until the axle was back in the Jeep to add the gear oil. The new cover held almost a quart more than the stock cover did.

The result was a smooth running rear end with no noise. I expect it to last a long time.

Parts used:

Timken 8.25 rebuild kit
Carrier bearings and races
Pinion bearing and races
Pinion seal
Pinion nut
Gear marking compound
RTV for the cover seal

Axle seals
Gear oil
Pinion Yoke
4.10 ring and pinion set
Blue Torch Fabworks cover

Technical info came from this source

1966 El Camino on Ebay

I have always loved El Caminos. My first car was a 67 El Camino. But I gave it back to my dad after only a couple weeks driving it. I just could not keep up with its thirst for fuel. And that was at mid 70’s pricing.

We still have that El Camino. It has been slowly working its way up[ the project list for a rebuild.

This one looks like a pretty nice basis for an El Camino Project as well.

Ebay 1966 El Camino

Weird Jeep Vette hot rod

I like Jeep rods. They are usually something a bit different. I like the ones with traditional hot rod front suspensions and T bucket styling.

Even better, I like the ones that retain four wheel drive and clearance to actually go in the dirt even if not to the rock gardens.

This one however has none of those qualities. It is different but not in a good way for me. It simply qualifies as weird. But it is for sale, if it strikes your fancy.

Jeep Vette Hot Rod

New trailer tires from eBay

New trailer tires from eBay

I guess when you live in the country; you get excited by small things. My little red trailer has seen a lot of use over the years; mostly by people besides me. I have used it to help friends move furniture, my son has used is for a mobile coffee bar and it has hauled plenty of lawnmowers and other small bulky items. It makes a good substitute for a pickup truck.

The bed is made from a sheet of 4 by 8 plywood so it is about he same size as a pickup truck bed. The bed also tilts making loading and unloading easier. It has 4.80 by 12 tires on four lug wheels.

I have not seen my trailer in a while because my son has had it. He left it at my Dad’s place because the tires would no longer hold air. They had gotten in pretty sad shape with a lot of dry rot although the tread was still good. The leak turned out to be the valve stem. I had just let it set because it was always used more by other s than by me anyway.

When my Dad offered to buy tires so that we could use it again I quickly accepted the offer and began tire shopping. My first stop was Tractor supply. $57 each for the little tires sounded sorta steep. And I would still have to mount the little buggers. At one time they had tire and wheel combos cheaper than just the tires but that was a long time ago.

I shopped my other favorite stores, Northern Tools and Harbor Freight. They had similar prices. Still more than I thought the little tires should be.

I began searching ebay and found the tires at a more reasonable $42 each including shipping. But I decided to do a little more searching because buying the tires still meant that I would have to mount them. I have had bad experiences with little tires in the past. I much prefer mounting big heavy Maxxis mudders on my Jeep than fooling with the little trailer tires.

I found an auction for tires and rims for not much more money. I le the first one slip by and the second one went for more than I wanted to pay. But I was finally able to buy at less than $55 each. I had not noticed in the first auction that a hub was also included in the deal. When the packages arrived, I found that both wheels had a brand new hub attached.

I asked Dad to bring the trailer to me so that I could change them in my shop. I did not realize how bad the one tire leaked. He said he had to stop and air it up eight times on the way to my house. Good thing he had thought to bring his air tank. I had never bought a spare tire for the trailer.

I put the back of the trailer on the lift and raised it up enough to get the tires off the ground. I had forgotten that the wheels are held on by lug bolts rather than studs and nuts. I seriously considered putting on the new hubs I had just gotten because they had studs and nuts. But after spinning around the old hubs and feeling how smooth they ran, I just decide to put the new wheels on.

I had a bit of trouble getting the holes lined up since the trailer hubs don’t have an alignment pin like Volvos do. I finally learned to spin the hub cap and hold the wheel to line up the holes and get one bolt started. After that the others went in easily. With all eight bolts in and snug, I set the trailer down and torqued the lugs to 70 ft lbs.

I then began looking for a place to mount the one good tire for a spare. I still have not decided yet. Putting it on the tongue will interfere with the tilt mechanism. Putting it on the side with prevent loading wide items across the top of the rails. For now I will just leave it in the deck and move it around as needed.

I am looking forward to loading up some scrap metal and taking it to the recycler. It is nice to have my little trailer back home and with new shoes too.

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