The bearings in the rear are easy to replace. Make sure the bearings are tight fitting into the axle housing!! If they are not pressed in they will eventually push the axle seal out, blow fluid all over your brakes, break in pieces and score your axel. The carrier bearings are pretty easy as well but make sure you keep the spacers together for each side. Most times you can get away with putting the same spacers back in as long as they aren't smashed due to bad carrier bearings. Do not attempt this job unless you plan to replace all the bearings including the pinion bearings. If your carriers are bad, stress is put on the pinions and the axel bearings as well and it will make noise!!

Do not attempt this job without a slide hammer, bearing / axle seal attachment for the slide hammer, and a bearing / seal driver. You will also need access to a shop press for replacing the carrier bearings and a decent puller to get the old ones off the carrier.

A little hint - You can buy all the parts and the special tools for a lot less than most of these guys payed to have it done by a garage.

 

I replaced the carrier recently, like last summer, and was hoping to not have to replace anything else.

Looks like I have grease on one of the rear brakes now, so I intend to open it all up again and replace the axle bearing and seals. Hopefully, I will not have to replace the axles. Problem is, I am going on vacation in 2 weeks, about a 5 hour drive one way, and I was hoping to not spend a lot of money right now on my '98 F-150 extended-cab.

I don't have the tools, so from what I have seen, I am looking at about 140-160 for the slide hammer and seal puller and about 30 for the parts, w/o any new axle costs.

The axles had some wear on them and I was told I should replace them as well at the time, but I thought, naaa, next time or as they get worse. Of course, this would probably mean the carrier would need replaced again and maybe the pionon seal, which wasn't replaced last time either.

I am going to put it off till after vacation and buy the tools then and do the repairs at my leisure. I will probably borrow someone else's vehicle to drive for the vacation though.

My biggest concern was that if I got the axle bearings out and the ones I had to put in needed pressed in, would there be a tool to do this or would I have to take the axle housing off and take it in to some shop?

Thanks again,
Rich

 

Many times I have witnessed "do it yourselfers" do more harm to their diff. or transmission. If you cannot afford to have this done, please reconsider before doing it yourself.

Some of the tooling to repair a diff.: micrometer, dial indicator (preferably one with a magnetic base), impact gun and some sockets, hammer & a bronze or copper drift.

To replace both pinion cups and cones, You first must remove the rear diff. cover & drain the lube. Mark the respective diff. caps (so you get them back on the same side that they came off of--diff. center section is machined and caps are not interchangeable or future failure will occur). Remove axle shafts. Next, remove the diff. ring gear carrier assy. (this may need to be pryed-out with two prybars), do not let carrier assy. fall on the ground--you may chip ring gear, make a mess or it could fall on you and cause bodily harm.

Driveshaft will need to be unhooked and pinion nut removed. Use a suitable brass or copper drift--strike drift with hammer & blast pinion out the rear of carrier (You will probably need someone to catch pinion when you are driving it out of the housing--to prevent damage to pinion). Crush sleeve should be on shoulder of pinion (remove it with your fingers). Next, remove inner pinion cone (you may have to take it to a machine shop or local shop that has a press or puller to remove it). Have new inner pinion cone installed (be sure shim under old cone is re-installed before installing the new inner cone).

Remove old seal & old outer pinion brg. (cone). Install new outer cup & install new inner cup (be sure they are seated in the housing--or future failure will occur). Install new crush sleeve on shank of pinion before inserting pinion in housing again (you will probably need someone inserting pinion from inside of housing, while you are in front of housing installing new outer cone) Use a suitable driver (or flat punch to drive new outer cone on pinion).

Most importantly (this is where most people mess-up): use an impact with old nut to starting drawing down (tightning) the old pinion nut to the yoke. CAUTION. As You slowly draw the pinion nut tighter, take notice frequently that you still have in & out play on the pinion yoke. When you have no in and out play on the pinion and there is almost no drag (when you spin the yoke), You are very close to preload. If you have access to a Ford shop manual--you need to find out how many pounds of resistance you need on the pinion pre-load (I do this by feel, you should not do this by feel). This is done with a small hanging type scale (like the one you would weigh a prized fish that you caught at the lake or river). If You overtighten the yoke--dis-assemble the pinion, start over with a new crush sleeve or future failure will occur.

After initial pinion preload is set: reinstall diff. carrier assembly (start with same side spacer's & shims on their respective side that they came off of or future failure will ocur). You may need a diff. side bearing shim kit to obtain the correct backlash & diff. side brg. preload, or future failure will occur. Diff. side shims are in different thicknesses (this is where you need the micrometer).

Be sure that diff.side spacers & cups are firmly seated into the housing (if not, you may break one on the main diff. caps--then you will need another complete axle housing). Be sure that diff. carrier is not super tight (when installing) or super loose--or future failure will occur. Your objective here is to obtain a diff. side (slight preload if you are using used side cones) and at the same time you will use the different size spacers (or shims) to obtain the necessary backlash (distance between the R/P to work correctly--otherwise, it will burn itself up, whine howl, or shuck its teeth). Backlash should be approx. .008" to .012". Backlash is measured with the dial indicator.

Once backlash is set, and caps are torqued the final time, remove pinion nut and yoke. Install the new seal. Again, tighten the "New" pinion nut down, being Very, Very, careful not to overtighten the pinion bearing, or future failure will occur.

Re-install driveshaft, new axle bearings and axle seals, silicone rear cover back on and start the axle lube fill procedure. Add friction modifier to the lube if you have L/S. Fill axle with lube, jack-up one side, wait about four minutes, bring axle housing back to level, then refill & jack-up other side, then check lube level. If axle tubes are completely cleaned, when diff. was dis-assembled--you need to make sure You get enough lube back into complete axle housing assembly or You may burn-up an axle brg.

I wish you the best of luck, should you choose to do this job yourself. Did You notice how many times I stated "or future failure will occur"? If you are like most truck owners, You don't want any future failures. gearmanx17

 

Federal Mogul part number for 8.8" diff. rebuild kit is RA311. Diff. rebuild kit should come with pinion seal, crush sleeve and new pinion nut. Also, kit will include new pinion cups and cones and diff. side cups and cones.

Side, differential bearings can be purchased as a kit (per side), if needed individually. F/M# A36. Axle seal# 8835S.

Some other companies will sell a pre-packaged kit that will include all of the above, plus new ring gear bolts, thread locker and silicone sealant.

In the past I have dealt with Blumenthals in Oklahoma City. They are the best on differential kits. Memory tells me that they probably have a website.