axle rebuild

1993 CHEVROLET SILVERADO
167,000 MILES • 5.7L • V8 • 2WD • AUTOMATIC
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JASONPYZO
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I have a 10 bolt 30 spline 8.5 axle. I am not replacing the gears and my book calls for .005 to .009 backlash on new gear sets, is it the same the same when you reuse the gears or is it different?
Sep 3, 2016 at 2:55 PM
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HMAC300
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check to see what you have before you tear it down which you probably have it torn down already..005-.009 is nominal but you can go .004-.012 is spec. if you are way off then pull your shims and switch sides you probably did not mark them then forgot where they went. Just make sure your bearings are seated well and that if you changed pinion bearings get a new crush sleeve and make it no more than 15 inch lbs. torque to turn on pinion with it seated and crush sleeve crushed. if old bearings are used then it should be no more than 5 inch lbs to turn.
Sep 3, 2016 at 3:35 PM
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JASONPYZO
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no it's already torn down, I'm changing the carrier to limited slip instead of stock open carrier and my service book says not to reuse the factory shims. which is one each side and you wouldn't be sure of the preload for the carrier. It basically says once you establish the shim packs on either side you add .004 to each pack to preload the carrier. I tried the factory shims at first and got .009 backlash be once I seen the note about not using the factory shims I took them out. Also I know the pinion preload, do you know if there is one when you have the carrier in to?
Sep 3, 2016 at 7:40 PM
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HMAC300
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there are shims behind bearings on pinion and the two sides on the carrier to set back lash in order to see carrier preload the gear must be off with shim pack installed and caps on to see what you have. if you have a total of about 20" preload turning pinion WITH carrier& gear installed you should be ok. to take carrier preload you need to do it from the axle not pinion. but gear must be off if you have 10-15" preload that is OK
Sep 4, 2016 at 7:38 AM
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JASONPYZO
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do you think this a acceptable pattern on the old gears? Also my backlash is a .008 right now,or do you think I should shim away for the pinion .003 and recheck?
Sep 6, 2016 at 1:21 PM
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HMAC300
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where arrows are in pic is where it should be . but the back looks pretty good. if anything you might want to move the pinion in Of course caps should be on and torqued down when you do this so if not then do that and recheck. there are few other things to do when gears are set up which you really can't do at home and or makes it very hard so I'd leave it alone myself. backlash is fine.
Sep 6, 2016 at 3:00 PM
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JASONPYZO
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ok thanks I appreciate it
Sep 6, 2016 at 3:36 PM
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JASONPYZO
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Here it is with .002 added to the pinion, backlash went to .006. This one or other? I kinda think the other one but what do you think?
Sep 6, 2016 at 4:06 PM
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HMAC300
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leave it alone it's good enough
Sep 6, 2016 at 4:21 PM
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JASONPYZO
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lol, ok
Sep 6, 2016 at 4:42 PM
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JASONPYZO
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ok I have another question,when doing the crush sleeve are you supposed to have any play in and out on the pinion before the crush sleeve bottoms out ready to be crushed, or is that normal?
Sep 8, 2016 at 12:07 PM
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HMAC300
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there should be no play at all when it starts to crush you have to be very careful not to go to far because that sets the 5-10 inch lbs or whatever figure I gave you for preload on the bearings. if you didn't crush it and checked back lash then it's wrong everytime you add a shim to pinion crush sleeve has to be replaced.
Sep 8, 2016 at 12:39 PM
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JASONPYZO
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when I did the initial set up for the pinion and carrier I used sacrificial bearings for the pinion honed out ever so slightly so they would slide on the pinion with a little resistance. I pressed carrier bearings on and established pinion depth,backlash and gear pattern with the help from y'all and got an exactable gear pattern and backlash. Note all this set up was done of course with no crush sleeve. Now I press the new pinion bearing on the shaft with the shims and go to install in case, tightened the nut on yoke until it bottomed out on the crush sleeve and there is play in and out on the pinion in the case. could it be a wrong crush sleeve, maybe? or something else?
Sep 8, 2016 at 1:04 PM
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JASONPYZO
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old crush sleeve widths.588 and new one is .627?
Sep 8, 2016 at 1:14 PM
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JASONPYZO
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heres the new crush sleeve on the left and the old on the right, they look different on how they will crush. can that be a problem?
Sep 8, 2016 at 2:58 PM
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HMAC300
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looks like the wrong crush sleeve it may be for a 8.5 or 8 & 3/4 axle been a while . the new one should look like the old one and should slide on pinion if new one doesn't slide on pinion gear and is wiggling on it it's wrong.
Sep 8, 2016 at 3:18 PM
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HMAC300
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to verify it is an 8.5 axle it should have one of the series stampedon front rh tube it lookslike the wrong crush sleeve though. the ones shon in pic are for a8.5 30 spline what you have looks like for SOME 8.5 and 8.75 ring gears.
Sep 8, 2016 at 3:26 PM
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JASONPYZO
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ok thanks
Sep 8, 2016 at 3:26 PM
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HMAC300
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these were at rock auto btw
Sep 8, 2016 at 4:24 PM
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JASONPYZO
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The axle is 8.5 and 30 spline pre vin # by the dealer. Truck was bought brand new by my folks and handed down. Also I pick up a set of crush sleeves from Napa for 8.5 & 8.75 rings and the smaller one is still to big, going by what you say and that you are not supposed to have any play when you slide the crush sleeve over the pinion shaft and if thats so its still wrong. I seen the ones from Rock Auto and looks like the same one I got, going to try dealer tomorrow and see what happens or if you have another idea.
Sep 8, 2016 at 7:59 PM
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HMAC300
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the one you sent to me via picture is the wrong one you should have one that is similar in appearance to the pics I sent the one on the left looks to be the correct one in the pics I sent. At rock auto it even said 30 spline.
Sep 9, 2016 at 6:13 AM
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JASONPYZO
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I was wondering if you could tell me when replacing the shackles and all the bushings on the rear suspension, when fitting it all back up I have a tool box on the truck bed and the whole back on the inside of the extended cab is loaded with tools should I take then out when I put the tires back on and set it on the ground to tighten the suspension? Also should the shocks be on or off?
Sep 11, 2016 at 9:04 AM
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HMAC300
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jack the truck up and put jackstands on frame so weight is off spings, put shackles /springs/shocks on and let it down
Sep 11, 2016 at 12:47 PM