Jackman5003

all i'm doing is putting in a new carrier and all new bearings/seals. the thing is, pinion depth, do i really need to buy the expensive *** tool and do this or can i just reuse the old shim(s). i'm not changeing the gearing i just kinda, broke my GovLok system that GM never should have attempted with there O SO great enginerring capabilities along with my awsome spelling capabilities, lol...and now i'm going to replace it with an eaton pro series LSD along with bearings and seals as i have a whining noise since i swaped in this rear. is an 8.5 10 bolt from a 96 blazer, same set up as the other 10 bolts correct?

and one more thing, carrier bearing preload, how do i go about doing that? do i need to buy the special tool from GM or what?

86Z

iTrader: (4)

you may just want to take it somewhere and pay the labor, as tools will cost just as much and if you mess up, it'll cost you more, your car has a 7.5" 10 bolt

Jackman5003

no it doesn't...it has an 8.5 from a 96 blazer....

i was ganna purchase the tools cause i'ma be working on cars for a carrer and probably always have some sort of project car/truck so i figured i'd get them. a dial indicater you can use all over(don't know about now-a-days but it used to be, now everything just replaced if theres a hint of failure...) and a 1/4 inch torque wrench you use sometimes. just this pinion depth guage crap...thats the only tool in question...

Sonix

iTrader: (1)

ah, ok, you're putting this in an S15.
I have no clue if the 8.5 will fit right, but hey, you seem to think so, so power to ya.

dial indicator, and magnetic base can be had from mcmaster carr, or harbor frieight for ~$50. I got one from mcmaster, the kit that had both. Great deal, works just fine.

And yea, you'll use the dial indicator lots.

Gear marking compound (paint, yellow) is needed if you're swapping gears usually, not a special tool, but worth mentioning.

What tool were you going to get/use for pinion depth? I just did it by feel (and used a solid pinion spacer), but a dial type inch/lbs torque wrench is normally used. Cheap one for $20 would work, but I couldn't find one in stores, so I just did it by feel.

Carrier bearing preload? I have no idea what you mean by that ?

Try some searches, I know i've posted a detailed thread (2 or 3 actually) with pictures when I rebuilt my rear end, didn't do anything high tech or nothing, but you may find some helpful info in it, or others.

tom robison

google search rearend setup, you will find all the info you need.

ede

if you not changing the gears set you should be able to R&R the pinion and reuse the original shim as long as it isn't damaged with the bearing spliter. if it is put the same size shim back in. same goes for the carreir shims, just put them back where they came from. if it were me i'd recheck the depth and back lash even if i know, or think, it'd be ok. you'd check preload, carrier or pinion with a dial type in/lb torque wrench. i think the cheapest and easiest way to check pinion depth is to make something to use as a datum surface across the CL and use a depth mic or depth rod on a dial caliper.

unlike sonic i'll go out on a limb and say the blazer rear won't work, even if it fits and i doubt it'll fit either.

Sonix

iTrader: (1)

1) You basically have carrier shims (the ~1/4" thick discs) on either side of the carrier, that sets your ring gear left to right, closer or further from the pinion. That's checked for correctness with the gear marking compound, and watching for correct tooth pattern; right?

2)Then you have pinion depth, controlled via the crush sleeve/solid spacer. That's checked via pinion drag (inch/lbs torque wrench).

I know there's something else i'm missing here, the reason for using the dial indicator... What other spec is needed to be checked?

ede

pinion depth is controled by the pinion shim not the crush sleeve, if fact you'd dummy it up and check it without the sleeve. you'd also check it with a pinion setting too, dial caliper or depth mic not a torque wrench. you might want to check preload with a torque wrench.

tommy z-28

iTrader: (1)

I am in process of setting the preload on my new pinion bearings (new races too) right now. I have an old a$$ beam type 0-100 inlb tq wrench. Last night I crushed the sleeve too far (so i thought) and it took 30-35 inlb when rotating. Now, going by feel, you'd have to be insane to leave it that tight. Tonight put a new sleeve on and I have it currently set to 15inlb on the wrench, but the feel seems correct. Any tighter and i would think it would be tighter than most people would set their preload (not using a tq wrench).

Should I trust the wrench and torque to to 20inlb or leave it at 15inlb based on gut feeling? How much do they loosen up during break in.

PS. The big bearing is lubed well with gear lube, but the small one had only some motor oil rubbed on the race and the rollers. I didnt want it dripping onto the shaft while it was being pressed on during assembly. It may be slightly dry.

Sonix

iTrader: (1)

What's the spec again? It's a range isn't it?

15inlbs should be totally fine. I did mine by feel completely, still runs.

When the diff is complete, and you fill it all up with fluid, rotate it around a bit, that'll move fluid through it all. Once you start moving the vehicle it'll also throw around enough fluid. I'd douse a bit of gear lube on that small bearing if you can reach it.

Jackman5003

the spec is 15-25 pounds for street use and 25-35 for race use. i set mine finally to 20 inch pounds. so right about in the middle. when i got the pinion in and all i had the rear on jack stands so i just flipped it down so the yoke pointed at the ground and filled that small portion of the rear where those 2 pinion bearings are with lube and spun the pinion a couple of times. and when i filled the rear finally i lifted up on the drivers side with a jack, left it for a couple minis and spun it a couple times, let it down and repeated on the passengers side. of course i cheaked the level afterwards and it was a bit low, so you just top it of and you should be good until your next change. which i'm going to do after about 1000 miles or so to get rid of all, if any, particles from the bearings and clutchs breaking in.

Pat Hall

iTrader: (31)

The dial indicator is used for checking the amount of backlash between the ring and pinion teeth. If out of spec, it's corrected by shimming the carrier left or right. Acceptable range is .006-.012 with .008 being perfect.

tommy z-28

iTrader: (1)

If I were to up the torque to 20inlb tonight, would I have to remove the nut first and reapply loctite? Or could I just bump it ever so sligthly tighter to achieve my 20inlb? Its been drying for 24 hours by the time I get off work.

tommy z-28

iTrader: (1)

Thanks for the suggestions on the pinion preload....

Now I have too much backlash. Spec for my gears is .010 max .014. Im seeing .015 in most spots. If I want to get this in spec in one try, please suggest what amount to increase the left shim pack by and what amount to decrease the right shim pack (i assume same amount). Currenlt I have stock shims so ill measure and stack aftermarket ones accordingly.

Thanks for the help.

Jackman5003

don't use the stock shims. they'll compact and lose preload and backlash adjustments after time. go get an aftermarket shim kit and use the 2 little discs they give with it that you put the shims in between. it really is trial and error. and remember, you should have to at least tap the carrier into place, it shouldn't just fall right in and plup right out. then you'll know you preloaded the carrier bearings correctly.

tommy z-28

iTrader: (1)

Someone who has had to adjust backlash and found themselves higher than spec slightly, how much should be moved from the right side to the left side in order to lower backlash by .003 or .004? Not worried about carrier bearing preload, because as long as i use the same thickness overall it will be preloaded properly. The carrier is definately in there tight enough with this total shim thickness!

Pat Hall

iTrader: (31)

You don't want to jump too much in one try, so if it were me, I'd probably only add/subtract about .002-.003 intially and check your backlash again.

tommy z-28

iTrader: (1)

Well I think the thinnest shim that comes in my pack is .009 so that will be the frist try. I think i saw someone quote .009 as moving about .004 to .005 in backlash. The only thing that I see difficult with shims is that they are hard to measure stacked, becuase they have to be compressed some for a true measurement.

Is it recomended that I stick a .009 between the carrier adn the stock iron shim on the left side, and then just add a stack of aftermarket shims on the right side to compensate? Or should I just remove both stock iron peices?

Jackman5003

no, don't use the stock cast shims at all. go get an aftermarket shim pack. it should have come with your bearing kit. and you should have shims down to .002 or .003 inchs in that pack somewhere or else how are you supposed to make fine adjustments?

tommy z-28

iTrader: (1)

I have a shim kit. However none are that thin. But I can definately swap various sizes to make each side the total thickness I want.

You think that moving .003 to the left side will tighten up my backlash from a range of .015-.016 to about a range of .010-.012?