I'm in the process of installing new gears, posi, and bearings. I'm using the Ratech solid pinion spacer instead of the crush collar. I used an inpact wrench to draw the pinion bearing onto the pinion. Once the bearing bottomed out I tightened the nut by hand. Since i'm using the solid spacer I had to do this a few times before I got the preload to 25 in/lbs. Did I do any damage to the bearing by using the impact wrench? Also it took a lot of force to take the the bearing off each time. I had to beat it off with a hammer. If I screwed up the bearing, I'd rather change it now while the rear is out...

 

not 100% sure but i believe you're not suspose to use an impact on the pinion nut. i know i don't, i use 3/4 ratchet and 3/4 breaker bar.

 

Never ever ever use an impact on a pinion nut. Its one thing to zing the nut off if replacing the bearings, but putting together is a no-no. I have yet to see a pinion bearing last more than 1,000 miles after being put together with an impact. I know that other people are going to post and say thats BS, and its OK, but trust me, when customers come in and say that the rearend is loud, its often followed by "Goodyear or PepBoys just did a pinion seal..." and its obvious by looking at the races that the bearings were just pounded into the races. Even some of our "less trained" guys at the dealership who didn't know better ended up doing it again in only a few hundred miles.

 

So GMTech, you are saying that I toasted my bearing? I assume that the inner pinion bearing is ok, and the outter one got screwed up, correct? What pinion preload do you recommend?

 

20-25 in/lbs

 

One more question. If the impact destroys the bearing and races when installing the pinion, wouldn't the bearing get the same damage when the pinion needs to be removed? Since the bearing is now pressed on, a hammer is needed to get the pinion out of the rear. Since I have a solid crush collar I need to remove the pinion a few times.

 

Just put a new bearing in the last time you put it together.

Next time you do a rear, take an inner (cone), and hone it out with a brake cylinder hone until it just fits onto the pinion. Keep that one as a tool; once you get the shim selected, then put a new one in.

I use a breaker bar on the nut, and a 4' piece of 1½"x¼" strip stock with 2 holes drilled in it, to hold the yoke still.

 

Chris, to answer your question "did i screw up the bearings by using an impact?" Probably not. Just make sure you have 25 in/lb pinion bearing preload and you should be fine.

GMTech, I think your mixing two issues. "Goodyear or pepboys just did a pinion seal"...and now it's screwed up. That's because they usually just run the nut off, remove the yoke and seal, put the new seal in, reinstall the yoke and run the nut back on without checking pinion bearing preload. Of course they can't really because usually the carrier, axles and wheel/tires are still installed. So they get it too tight and it burns up the bearings.

Chris, you can follow RB8's advise on the brake cyl. hone or if you don't want to waste a bearing you can always hit the pinion shaft with some emory cloth where the outer pinion bearing rides. Do this until the lubricated bearing slides on the pinion shaft with a friction fit.

 

While we're on this subject, I have a few questions and I'm looking for some information. I'm planning on swapping the 3.23 gears in my 7.5" rear for a set of 3.73's and a G80 posi unit both from an S10. My questions are:

1. What are the advantages and disadvantages of using the solid collar as opposed to a crush collar? Are the solid collars reuseable? How much do they cost?

2. I'm planning on swapping the 3.23 gears for the 3.73's as stated before, and my car is currently equipped with 26 spline axles and an open differential (1988). However, since the 1990+ years with 28 spline posi's are all over the junkyard around home and can be had for $25 including ring and pinion gears, I'd like to swap the G80 differential from a newer S10 and the axles from a 1990+ F-Body to complete the package. I currently have a G80 posi unit that needs a governer, and the local Chevrolet dealer quoted $61. For that, I'll go and spend another $25 on another differential, and if I happened to find a 28 spline posi with the 3.73 (which will be very easy). This way I will be able to have the original gears that were with the differential from the factory, which I've read is necessary, or at the very least, a plus. My question is, will the newer 28 spline posi and 28 spline axles from an F-Body bolt into my existing housing without a problem? What, if any, special parts are needed to make this work, other than the normal bearings, gaskets, shims, etc.?

3. As Chris90Formula stated, he used an impact to draw the pinion bearing onto the pinion. I have been told before that the correct procedure is to have a qualified machine shop with a hydraulic press press the bearing on and off, taking care not to damage the shim that's behind the bearing. Again, I'm just looking for some reassurance that this is the correct procedure. Thanks everyone.

 

1. advantage: solid spacers don't deflect/deform under hard load like a crush collar. So the pinion bearings are more stable. Disadvantage: cost, maybe. Regular crush collar $3-$4 and solid spacer $15-$20. Solid spacers are reusable.

2. the 28 spline axles should interchange without problems. Only special parts would be the solid spacer if that's the route you want to go.

3. your talking about the inner pinion bearing-the one next to the pinion gear teeth while Chris is talking about the outer bearing. It doesn't have to be pressed on (but it's the preferred method) you could also use the correct bearing knocker and hammer it on. Put some lube on the pinion shaft and inner part of the bearing just in case you have to pull it off again to change depth.

 

I would not recommend using the carrier out of a S truck... more than likely it will be the infamous Eaton Grenade-Lok, which is unsuited for any kind of performance use.

The thing that makes you need to do a gear setup is the differences between housings, not the carrier. As long as you put moving parts back into the same housing, about 99% of the time you can swap gears and/or carriers and use the same shim thickness. The thing that is variable, i.e. that you select shims to fit, is the housing. So taking any gears, new or used, out of any housing and putting them into another housing, with the same or different carrier whether new or used, will necessitate setting the gears up to that housing. You don't really accomplish anything by getting gears and carrier as a unit from one housing; they'll need a full setup when you transplant them into another housing, whether they were a "set" before or not.

Axle shafts from a 90-up F car 10-bolt are kind of hard to find at a good price. People know what they're worth it seems. You'll probably have to buy a whole rear end to get them. Fortunately 6-cyl rears have the same axles as V8 rears.

But good luck!

 

Thanks for the advice, but I'm afraid I'm gonna have to go against your advice on this one RB83L69 and use the G80 posi from the S-truck. However, I have decided to go with the solid collar instead of the crush sleeve to to it's reuseability. This way, if it does break, it'll save me the cost of at least the crush sleeve. For $25 for a complete set of gears and posi unit, it's almost hard to go wrong. I mostly decided to use a factory posi unit because my motor is mostly stock, and I doubt that I'm producing enough power to break it. And as for installation and set-up costs, the guy I used to work for, a Stock and Super Stock national record holder, sets up our rear ends for us, so that install and setup cost is nonexistent. As for the 90+ axles, the junkyard has them for $12 a piece I believe. Also, thanks for straightening me out on the pinion bearings.

 

"Chris, to answer your question "did i screw up the bearings by using an impact?" Probably not. Just make sure you have 25 in/lb pinion bearing preload and you should be fine.

GMTech, I think your mixing two issues. "Goodyear or pepboys just did a pinion seal"...and now it's screwed up. That's because they usually just run the nut off, remove the yoke and seal, put the new seal in, reinstall the yoke and run the nut back on without checking pinion bearing preload. Of course they can't really because usually the carrier, axles and wheel/tires are still installed. So they get it too tight and it burns up the bearings. "

I agree, an impact merely tightens the nut, just like anything else. It's just easier for a 'rookie' to get it too tight with an impact. Impact or not 25 in/lbs of preload is still 25 in/lbs of preload. On new installs, I usually do it by hand using a big bar or a 'manual' impact(ever seen one of those?). Pinion bearing installs end up with the regular impact wrench, putting the nut right back where it was.