Hello. I recently found rear end problems in my (not clone) 1995 Impala SS. The car has 135,000 miles on the odometer. I have a chewed up stock auburn, stock 3:08 gearing in there now. My car is on jackstands at the moment. I’m not planning to get this done over night. This car is parked. This post is continued from an ABS post problem that is seemingly being a bad rear sensor that was chewed up by rear end broken pieces. Note: The car drove fine when I parked it. Still will luckily. But who knows how long. So here is my introduction to my rear end rebuild.
Feel free to tell me I’m on/ or not on the right Understanding track, plus picking up and quoting any bold questions I have in my post below. As I feel a need to know these things before I start. I’m still researching. Should be some good information and learning going on here for whoever. Probably going to buy a bearing brass,
And torque meter for pinion preload.
***Here is my quoted post from my ABS sensor problem turned rear end rebuild
First, I want to thank all of you for helping me on this post.
I’m starting a new post on my rear end rebuild soon. I will attempt to do it myself on my property. I am politely asking furthermore and would appreciate some input from people who know how it’s done while I do the rebuild. I’ve done hours of reading and watching trustful media on how rear ends are rebuilt. I worked as a lead man machinist in the past at a bearing manufacture. I used to finish machine (grind) bearings on all dimensions furthermore size matching raceway diameters to fit certain ball and roller diameter spreads to obtain correct radial play. After reading and watching video’s, I’m having a pretty clear understanding of:
1. Pinion depth
2. Ring gear backlash
3. The relationship of “pinion gear depth” to “position of healthy operational contact point of teeth on pinion and ring gear. (Brushed on yellow stuff)...Where it’s supposed to be
4. Spacing of shims on sides of differential carrier between carrier bearings and case to correct backlash of ring gear to pinion- to FSM spec. Need understanding of how tight the carrier should be between the shims though. No play obviously understood as backlash should not change or shift side to side (left right). I’m guessing the correct backlash and the shims that fit the tightest without exceeding preload is the ticket.
5. Test bearings vs depth guage for setup of pinion gear shim selection.
- I know the honing of the inner diameter (bore) of the pinion gear bearings makes for a slide fit of the two bearings onto the pinion gear shaft. This all to position pinion depth and “remove bearings easily” if I need pinion depth change by a pinion shim change.
- I know the pinion depth guage is used to obtain pinion depth without installing the carrier and testing with the gear tooth paint and dis assembling to add or subtract shims to achieve the sweet spot with the paint. (Heel, toe, peak, valley etc. if you will) note: Peak and valley moreso involves carrier spacing shims if pinion depth is correct.
Question: Using a pinion depth guage or not, “is it essential to use a pair of set up bearings (honed I.D)?”
I mean, I am figuring right now that even using a pinion depth guage the end result of pinion depth may need to be corrected and using a non pressed set of bearings will still benefit the builder. Unless there is a way of adding some sort of stack height (shim+ pinion gear width from face seats+ pinion depth to center line of carrier axis. <<<<let me know.
Question: If I purchase an Eaton posi differential or any “non stock” carrier differential, does the pinion depth still match the FSM spec?
Question: if I purchase a non factory gear set, for example a 3:42 or 3:73, does the new pinion gear depth change from the FSM? I’m guessing that the diameter of the pinion gear itself gets smaller and the ring gear diameter gets larger so YES the pinion depth changes and a number needs to be added or subtracted to the FSM spec along with the number attached to any specific pinion gear. In other words, pinion depth consist of 1. The with of the shim, pinion gear, pinion depth AND the shift of the pinion itself that takes place when a larger carrier diff ring is installed? Is this true?? This is all what I need to know which way to set up my rear end will be better-using a depth guage or not.
*Im guessing using a depth guage would be easier with rebuilding my rear end with an identical auburn and stock size pinion gear and ring gear pair and starting with my old shim.
*Im guessing not using a depth guage would be easier in the sense of not having to add all those numbers up and formulating pinion depth with aftermarket ratio change to the 3:42 or 3:73 (whatever it is if you will). This being if pinion depth changes from the FSM drastically with new ratios. I’m guessing it does since a larger ring would be going in-this resulting in a larger number in the depth reading from the centerline of the carrier.
⚙ Finally the reluctor ring gear that interacts with the ABS sensor. I need to know what reluctor ring goes with what “pinion gear and carrier ring set”. And, of the same importance. If the reluctor ring that goes with any particular “pinion gear and carrier ring—set” fits with any chosen carrier differential being an Eaton for example.
End note/s: My vehicle is going to be driven on the street as a regular driver. So, that being said, I hear Eaton differentials are for straight drag type driving and they can have cornering problems and make noise. I’m not saying they are not good parts. I’m saying I don’t want to pay for High performance parts to have my car making rear end noise because I went to Walmart. Further explanation is this. I hear just about everyone wanting a better than stock Auburn or recommending something other than an Auburn like an Eaton, Tru Trac, Locker, Yukon. Whatever it is... It don’t really matter. I may not be naming the correct names. What I’m saying is this. All I want is a reliable rear end with a gear change ratio. And no problems because I put something in my car that has no purpose as a daily tip driving city application. My example was an Eaton. I’ve read they are good but the reason is for the strip. My Auburn is 130k old I’m guessing. I don’t want any Eaton problems after 4 thousand miles because I don’t drag race and want to have an Eaton like everyone else. You see my point. Now if a performance carrier “differential” other than an Auburn is going to last longer than an 3:42 or 3:73 ratio with an new Auburn replacement, let me know and what it is. What I’m asking is this: Is it going to be a mistake rebuilding my rear end with a stock carrier and 3:42 or 3:72 ratio?
If like what people say, “3:42 and 3:73 are easier on transmission life” wouldn’t a stock Auburn have a longer life with the gear ratio change also? Let me know.
So what combo of parts should I buy? I know there is a whole bunch of information out there but I’m skeptical about asking questions on post that are so old as people may not respond wasting my time and putting extra stress on me. Although I am utilizing that information, anyone can’t be mad at me For wanting answers to my specific case.
Sorry for the long post. But this is where I needed to start. I will be copying and pasting this as an intro to my new rear end rebuild done by me thread in the drive train section of the forum. Please feel welcome to participate in my first rear end rebuild. I can appreciate and am probably going to need some honest true facts and direction.
Thanks.