i'm replacing the all of the bearings in the differential in my 80 LS. i got the sucker apart per fsm. i'm only replacing the bearings, not any of the gears. the pinion bearings are not so good and i decided to replaced the carrier bearings as well. at any rate, i read further and the fsm states that there are special tools needed to set the preload on the pinion bearings. i know that the preload is essential. has anyone done this without the special mazda tools and if so, whats needed to accomplish this?

 

one of the techs did his diff at the dealership, cause he had the tools, but he said he didnt need em.

if you are only doing bearings, and bought OEM bearings and new crush sleeve, you'd be ok just to put it back together. you do wanna check the pattern on the teeth, to make sure its ok, but it seems like if it was a factory build, and you use factory parts, it'll be ok

 

i ordered SKF bearings from napa. i THINK (dont quote me) they are oe replacements. i bought a set of front wheel bearings from the dealer for my 85 GS and they were SKF. here's hoping..i measured the sleeve and it was out of spec. i'll order one from the dealer tomorrow morning.

 

https://www.rx7club.com/1st-gen-archive-71/drivetrain-how-rebuild-your-lsd-711948/

 

Dave - please keep us posted!
Steve- wow! some article - archived in my personal RXTech files Thanks!!!

Stu Aull
80GS
Alaska

 

that was exactly what i was looking for! thank you for that writeup! tiem to archive that as well!

Stu, i'll see if ic an take some pics as i go and post them up. the teardown was the easy part

 

I'm really interested in this as well. My diff has started grumbling a bit on shifts; I have a spare diff I took out years ago that was also pretty tired, and would love to have some confidence in what I'm doing before I tackle refreshing it.

 

Glen, everything thus far has been super simple. the teardown was a breeze. the hard part will be making sure the pinion bearing preload is correct and the backlash is set properly. doing the job correctly is key in my eyes.

 

got the components hot tanked and got the new bearings pressed on tonight. the bearings weren't bad at all. they were no match for the press . i'll post pics of the clean parts!

 

going ot put the sucker back together today using steve84GS TII's writeup!

 

Good luck!

Main thing I want to learn on this subject; just how much "wear slop" can be repaired through bearing and seal replacement and readjustment, versus the need for new gears?

I gotta pull my old diff out of the box and see just how bad off it may be. It's been bagged and boxed for probably 8 years. Which means it only had about 22 years of wear on it...

 

its not worn or sloppy, just nasty bearing noise. the new bearings should fix the issue!