I have read several of the posts on this subject. I have decided because of the cost of having a shop do the work that I am going to replace my rear pinion bearings. I am not changing any gears all I will be doing is changing the 2 bearings. I know it is otherwise not recommended but $$ are what is in question. I have looked at 2 diffrent posts from SUBFORD and StrangeRanger. One questions I do have is how much can measurments be changed if I pull all the same pieces out and put all back in the same way with all the same measurement checks?

 

Food for thought - If the pinion bearings are bad, say they're pitted and gouged, metal from the bearings is circulating through the axle fluid...and into other bearings.

Pinion depth won't change, backlash won't change. Pinion bearing preload will change and must be reset with a new crush sleeve and an inch pound torque wrench. Really, even though money is a concern, if you're gonna pull the axle down to replace one or two bearings, you may as well do them all - only ones that are left are the two carrier bearings and axle bearings.

 

About 3 months ago I did check the fluid level in the axle. When I pulled the plug I did not see any visable filings but did have 1 inch or so long wade of what looked like grey grease (plag seems to have a magnet). Would this be wear over time? Or do I need to look in the bottom when I open up.

 

You should always check the old oil sediment every time you open an axle, regardless of why you're opening it.

Yes, the plug has a magnet, and it should never be put back in with anything on that you can clean off.

Bearings are VERY precisely built, but I still wouldn't trust them to be THAT identical to the originals. No matter who does the work, the proper tools should still be used. You can borrow/rent a dial indicator & check backlash, & set the gear pattern to spec. Read the captions of the photos & diagrams in the 8.8" Axle album in my signature link, and read this page. This one shows some of the specs.

 

Do you know of any sites that specs for 9.75 ring and pinion.

 

yeah. i do. lol i have tons of them. i am doing the install right now on my truck to 4.10's with the 9.75. i am going to open up another link here in a few minutes. check it out.

 

Go to that last link in my previous post & change the "8.8" at the end of the URL to "9.75". Or you can go back to the homepage of that site & then drill down to the 9.75.

 

My truck was manufactured in 6/99. I found that ford changed there pinion in mid 99. So the one of the pinion bearings is diffrent for later 99 and on. I ordered a master bearing kit from RPM outlet.com $119 (best price I found). The kit thay list is for the earlier model (for future refrence.) The following is are the bearing numbers for the late and earlier model diffrences. (Late cup- HM89443 inner dia.1.3125 1.125 top to bottom) (Late race HM89411- 3" inner dia. .9063 top/bottom 1.1563, I believe this measurement is the tapper in the race)
(Early cup M88048- 1.3125 inner dia. .875 top/bottom) (Early Race .6875 top/bottom .8750 I believe this measurement is the tapper in the race) I think this is pretty accurate.

 

Mike, when you do it man take pictures of EVERYTHING and post them up. you wouldn't believe how many people are looking at doing the same thing you are and it would be a ton of help.

 

I will definatly post pics. For the record "Ihave not done this before" I know it is highly recommended not to do this without experience. Money is an issue so I will document well. Thank the lord for Harbour Freight only had to spend $140 for the tools I needed.

 

look man before you even start, research and print EVERYTHING you can find on your rearend. if it's ANYTHING like mine, you are going to need EVERY piece of information. while it may be different pinion bearings, if you have the 9.75 rear end everything else should match just about what I have. i am going to go tonight and set my backlash and everything. if you can, hold off on starting till i can get you some pics. it will make EVERYTHING alot clearer and easier to understand.

and yea, harbor freight is where i got what i needed to. one piece of advice. get some emory cloth and some polishing stones for a dremmel or electric drill, whichever you have. it'll help out.

 

One thing though. I am not putting in a new ring and pinion. Just bearings, from what I understand my backlash should not change since I will not have to use new shims.

 

Backlash shouldn't change, but there's no reason you shouldn't check it while you've got it apart.

 

I will document everything. I went back and bought a micrometer and magnetic base today.

 

Is it imperative to use a dial torque wrench when checking bearing preload? or will the clicker work fine?