10-bolt setup...final pattern check, posts #54 & #55 - 4/20/2008

[AddictedOffroad]

Ok... standard for new ones is what, around 20in/lbs?

Luckily I got a dial-wrench that reads 0-30in/lbs...

13-15in/lbs for new bearings. Use that link I gave you before. It lists most axles and bearing preload for new and used bearings.

 

[jonrpick]

13-15in/lbs for new bearings. Use that link I gave you before. It lists most axles and bearing preload for new and used bearings.

Yeah, it's still pulled up...

Thanks again.

 

[jonrpick]

New pattern...

I'm getting very pissed about this thing.

Gripe #1...Focking shim kits.

I started with the factory shims, then bought a shim kit from Advance Auto. It's fine, except the smallest shim is a .010". I can make a change as small as .005" if I swap a .020" or .010" for a .015" shim. That's not small enough of a change.

So I ordered the adjustable shim kit from 4Wheel Parts. Same BS, except this one only has .010" shims. FAIL.

The guy in my rebuilding video has a shim pack with .002" shims.

So I finally found a REAL shim pack that goes all the way down to .001". Now we're talking. But the company that sells it doesn't have online ordering or prices posted for their merchandise. WTF?! I can't find this shim kit anywhere else, so I'm probably going to have to call them and order it.

Gripe #2...bearing splitters

I pressed my new inner pinion bearing on after removing some shim as was suggested. It ended up needing MORE pinion shim, but no biggie...

HOWEVER... in order to change the shim, I had to press the bearing off.

FAIL.

The cheap Harbor Freight bearing splitter ripped the cage off the bearing.

(pausing to regain calm)

So, I used the inner section of the bearing to create a tool to press on the new replacement bearing that I would buy later that day. Bonus. I also returned the POS bearing splitter, and sought advice on which one to use.

Anyway, the shim was thinner, and it made the pattern screwy. So I needed to remove the brand new bearing. Well, I settled on a machine shop. The dude was using an OTC 1123, the exact splitter recommended to me. It almost ripped the cage off because it couldn't bite the inner race. He stopped before damage ensued.

I tried machine shop #2. He got it off, but damaged the bearing. So now I need brand-new bearing #3.

So I came home, took the original inner pinion bearing, and ground out the inside to use it as a setup bearing (fock this pressing on and off business). I ran a new pattern with more pinion shim than I had originally... Backlash is within spec (don't remember exactly, but somewhere between .006"-.010").

This pattern is with the original bearing being used as a setup bearing, so I don't have to press anything until final assembly.

Coast side, since it's the relevant one...

What do you guys think???

 

[Hogback Fabrication]

Any time I'm setting up gears I use setup bearings. You learned the hard way how difficult it is to remove bearings once they are on there.

The reason that most shim packs aren't as thin as you would like is this:

If you need a .217" thickness shim (for example) you should be able to create that thickness with what they provide.

Sure, they don't provide a .200", .015" and .002" shim (the easiest and maybe the most logical way) but they probably provide some combination of shims that will get you to .217". Document the thickness of each shim and figure out a way to get to the thickness you need.

Your pattern looks fine to me. Are these gears used?

 

[jonrpick]

Any time I'm setting up gears I use setup bearings. You learned the hard way how difficult it is to remove bearings once they are on there.

The reason that most shim packs aren't as thin as you would like is this:

If you need a .217" thickness shim (for example) you should be able to create that thickness with what they provide.

Sure, they don't provide a .200", .015" and .002" shim (the easiest and maybe the most logical way) but they probably provide some combination of shims that will get you to .217". Document the thickness of each shim and figure out a way to get to the thickness you need.

Your pattern looks fine to me. Are these gears used?

The shims are .100", .020", .015" and .010" on one shim kit... the new "adjustable one has the two outers that add up to .200" and a bunch of .010"s. The only deviation from multiples or sums of those measurements are basically explained by slight flex in the shims which isn't present when you bear down a bit with the calipers. They measure pretty much right where they need to be.

Setup bearing...lesson learned, and a new tool created. Actually 2 tools. The first "new" one that I destroyed got ground out as well. It's inner piece now acts to press on the new bearing...

I'm somewhat, but not entirely surprised that 4Wheel Parts didn't have a better shim kit. After all, the 4x4 hobby involves gear changes quite often.

I'm REALLY surprised that the badass speed shop in downtown Atlanta didn't have them either. They have everything. Sorta like a local Summit retail store...smaller, but a lot of high-end stuff for people who actually race (which also involves a lot of gearing changes).

Yes, the gears are used, hence me only showing the coast side. My big concern is... .480" total shim came out, and that much is in there now. But this doesn't really account for pre-loading the new carrier bearings. On the DVD, the guy set up the backlash, ran the pattern, etc...but then at the end, during final assembly, he added .002" of shim to each side of the carrier to pre-load the bearings a bit.

Again...without a *good* shim kit, there's no way for me to add that much (or that little).

So the big question is...what're your thoughts on carrier bearing pre-load?

 

[jonrpick]

Real shims!

Check it...

I'd bought two different shims packs. One was a set you just stacked, and the 2nd was "adjustable". The adjustable packs have outer shims that nest together with the thinner shims sandwiched in-between.

The stacked pack had as small as .010", but if I took out .010" and put in .015", I could make a change as subtle as .005". Not good enough. So I ordered and waited for an adjustable pack. Nothing ending in "5", therefore the smallest change was .010".

So today I located a shop in town that sells a REAL adjustable shim setup. This thing is a work of art.

The old shim packs (adjustable and stacked):

The new ones...

Look at the way the outers lock together to keep the whole pack from spinning on itself. Another problem with the other packs is the total amount of shim wasn't enough to properly pre-load the new bearings.

This pack came with a total of about .660" worth of shim... the axle only had .480" to begin with!

This pack had .007" and .012", meaning I can swap either with a .010" shim to move it .002" in either direction.

I'm just waiting on the kerosene heater to warm up the garage. These shims will let me get it just right AND properly pre-load the bearings.

w00t!

 

[Hogback Fabrication]

Sorry I didn't see your post before, I don't think carrier bearing preload is all that important. Its certainly not anywhere near as important as pinion bearing preload.

The way I was taught and how I've always done it is this:

You should have to tap the carrier into the housing with a deadblow hammer. You shouldn't have to wail on it to get it in there but it shouldn't go in by hand either.


I have seen a spec before for carrier bearing preload. Once the gears are installed and the carrier and everything is in the housing you measure the total resistance at the yoke; i.e. if your pinion bearing preload was 20 in.lbs. without the carrier, the carrier should add another 10 in.lbs (I made up the 10 in.lbs part, I've never bothered with it so I don't know the spec).


Generally when I am setting the pattern I get the carrier so there is no side to side movement (checked with the dial indicator) but so the carrier slides in by hand. Once I get the pattern right I add a couple thousands to each side and tap it in with a hammer.


As far as your shims problem goes I've never had any issues with the shims kits I've used. Mine have always had shims in tons of different thicknesses. I think I've always used install kits from Yukon, Richmond, Motive, probably some others.

That new shim kit you got looks pretty sweet though; I hate diffs (like the GM stuff other than the 14 bolts) that use the shims outside of the carrier bearings. Its easy to bend shims when you're installing them, seems like your kit would probably eliminate that problem.

 

[Chevy305]

wow you really care about getting this dead on balls acurate. When I did my diff I eyeballed it and luckily it turns out I ended up with a .008" backlash. The diffs been holding up real strong ever since.

 

[jonrpick]

Sorry I didn't see your post before, I don't think carrier bearing preload is all that important. Its certainly not anywhere near as important as pinion bearing preload.

The way I was taught and how I've always done it is this:

You should have to tap the carrier into the housing with a deadblow hammer. You shouldn't have to wail on it to get it in there but it shouldn't go in by hand either.


I have seen a spec before for carrier bearing preload. Once the gears are installed and the carrier and everything is in the housing you measure the total resistance at the yoke; i.e. if your pinion bearing preload was 20 in.lbs. without the carrier, the carrier should add another 10 in.lbs (I made up the 10 in.lbs part, I've never bothered with it so I don't know the spec).


Generally when I am setting the pattern I get the carrier so there is no side to side movement (checked with the dial indicator) but so the carrier slides in by hand. Once I get the pattern right I add a couple thousands to each side and tap it in with a hammer.


As far as your shims problem goes I've never had any issues with the shims kits I've used. Mine have always had shims in tons of different thicknesses. I think I've always used install kits from Yukon, Richmond, Motive, probably some others.

That new shim kit you got looks pretty sweet though; I hate diffs (like the GM stuff other than the 14 bolts) that use the shims outside of the carrier bearings. Its easy to bend shims when you're installing them, seems like your kit would probably eliminate that problem.

Well I just spec'd them out on the kitchen table--I measured each one then wrote the measurement down on each one with a sharpie. It makes finding the right one very quick and easy.

The only problem I might run into is that the outers on these are very thick...around .220" I think. So I may again be limited. Would it be entirely ghetto to mix and match shims from the other packs to get it right?

 

[jonrpick]

wow you really care about getting this dead on balls acurate. When I did my diff I eyeballed it and luckily it turns out I ended up with a .008" backlash. The diffs been holding up real strong ever since.

I can't afford not to for a couple of reasons.

1) I've half-assed things before that turned out badly. Sometimes it works, but I have this sick feeling every time I see something that I could've done better.

2) I'm really wanting to learn to do this, THE RIGHT WAY. As I've said before, my ultimate goal is to be able to literally fix everything on the truck, from engine, to tranny, all the way back to the axles and everything in between.

I am going through a lot with this, but think of it this way. The front is gonna get re-geared a *lot* quicker... I'm either already have or know exactly what I need to get it done. I'll make one purchase, or a series of purchases all at once, and just do it.

Of course, then there'll be a thread in here on balls joints and steering...

But hey, in the end, I know it'll be right.

 

[Hogback Fabrication]

Well I just spec'd them out on the kitchen table--I measured each one then wrote the measurement down on each one with a sharpie. It makes finding the right one very quick and easy.

The only problem I might run into is that the outers on these are very thick...around .220" I think. So I may again be limited. Would it be entirely ghetto to mix and match shims from the other packs to get it right?

You should be able to mix and match shims with no problem. The little tabs that your new shims have may not work with the old ones.

 

[Hogback Fabrication]

I can't afford not to for a couple of reasons.

1) I've half-assed things before that turned out badly. Sometimes it works, but I have this sick feeling every time I see something that I could've done better.

2) I'm really wanting to learn to do this, THE RIGHT WAY. As I've said before, my ultimate goal is to be able to literally fix everything on the truck, from engine, to tranny, all the way back to the axles and everything in between.

I am going through a lot with this, but think of it this way. The front is gonna get re-geared a *lot* quicker... I'm either already have or know exactly what I need to get it done. I'll make one purchase, or a series of purchases all at once, and just do it.

Of course, then there'll be a thread in here on balls joints and steering...

But hey, in the end, I know it'll be right.

That is all pretty admirable IMO.

You're taking the time and effort in learning how to do it right the first time, not many people would

 

[jonrpick]

You should be able to mix and match shims with no problem. The little tabs that your new shims have may not work with the old ones.

You're right about the tabs. I meant using the thin, yet full-sized shims on the outside of the new pack. I won't have to I don't believe. The original shim amount that came out was total .480", and about .484" is going back in. I'm pretty sure I just got it nailed down.

That is all pretty admirable IMO.

You're taking the time and effort in learning how to do it right the first time, not many people would

Thanks! After this I get to learn to rebuild an NP208 (they got a DVD for that too). After I get the mechanicals straightened out, I'm getting a used 700R4 and a book and DVD for it as well. Like I said, I don't want to take this thing to a shop ever again, unless it's MY shop.

 

[jonrpick]

Final pattern check before crushing the crush sleeve... Please look at it for me!

Here it is... I ran the pinion in .002" deeper just to see. I see to like this pattern better. I wish I had new gears so I could read the drive side.

The pics weren't coming out clearly because of the way the light is reflecting in the garage. So I made a Youtube video to show the pattern.

Edit... video is processing... will be available in a moment.

Edit #2... video is working, but lost some quality. Still, you should be able to see. I added a pic in the next post.

 

[jonrpick]

a decent pic:

 

[Hogback Fabrication]

Did you thin the paint at all? Are you keeping pressure on the carrier while you take the pattern?

The pattern is pretty tough to see but it looks centered to me.

 

[jonrpick]

Did you thin the paint at all? Are you keeping pressure on the carrier while you take the pattern?

The pattern is pretty tough to see but it looks centered to me.

I didn't thin it, no... I did keep pressure on the carrier while turning the pinion.

For some reason, the camera isn't picking up the contrast between the paint and the pattern as well as it should.

If it looks good I'll go ahead and crush the sleeve.

 

[readymix]

I'd run it like that.

 

[Hogback Fabrication]

Mix some gear oil with the paint and take another pattern.

 

[jonrpick]

LOL...

Well, I can take another pattern, but I just yanked off the setup bearing and pressed on the new inner.

I feel pretty good about this pattern though...when it's back together I'll take a pattern just to check.