Pattern check, first timer needs reassurance

[Captain Ledd]

SEE POST #15

Edit: 4.56 gears in an explorer 8.8 if your curious.

So I measured everything super carefully, except when I did the carrier shims. I re-used the old large shims from the original gear set, and just stuck a bunch of shims on the right side until it tightened up. backlash was .03 or .04 something I quit reading the gauge at that point.

Took all those shims out and stuck them on the other side, .010 backlash. Hot darn I'm in spec! so I did a pattern test.

Personally I think the pinion is a little deep, but I only put .028" worth of shims in it (pinion was marked -2, Ford racing gear set).

I also think there's a lot more tooth contact than I see in other gear sets. I'm not sure what to do about that, if it's even a problem.

I'm a little uneasy that I got it this close my first time through just jamming shims in it to take up slack lol

**edit edit** - I'm going to take another .002 out of the pinion and see where things are. Did some more fiddling just for the hell of it and came to that conclusion.

*Ignore this post*

http://i129.photobucket.com/albums/...ger dashboard removal/Rear Axle/100_08671.jpg

http://i129.photobucket.com/albums/...ger dashboard removal/Rear Axle/100_08661.jpg

 

[Captain Ledd]

Alright, fiddled with it a little, decided to get the pattern away from the toe and centered as much as I could, I do think I need to shim it juuuust a tad closer to the pinion. Backlash is now at .012"

Does anyone else think I need to set my pinion a bit farther back? None of my instructions are particularly clear, I'm combining 2 different sets.

Ignore this post

Drive side:
http://i129.photobucket.com/albums/...ger dashboard removal/Rear Axle/100_08681.jpg

Coast side:
http://i129.photobucket.com/albums/...ger dashboard removal/Rear Axle/100_08761.jpg

 

[Hahnsb2]

I think I'd go a touch deeper on the pinion and a bit tighter on the backlash.

 

[Captain Ledd]

I think I'd go a touch deeper on the pinion and a bit tighter on the backlash.

Yeah, I've attempted to mess with it more but ruined a few shims, so I spent most of today running around trying to build a case spreader. Apparently a aluminum 3/8" turnbuckle is the heaviest thing anybody has around here. pfft. Barely even long enough at that.

So you mean move the pinion TOWARD the carrier or AWAY from the carrier? I thought it was contacting the base of the tooth (move the pinion away).

 

[Hahnsb2]

Deeper as in deeper into the housing (fewer shims).

 

[Captain Ledd]

Alright, we're back at this again. (yes it has taken me this damn long to fiddle with it)

I'm now at a bit of a conundrum, one side tells me my pinion is too close, the other side too far away. WTH?

Apart from that I think I've got it pretty well centered?

Backlash = .012" (spec says .011"-.016")

DRIVE: Pinion is too far away? Contact patch arc's up towards the top?

COAST: Pinion is too close? There's some pretty bottom heavy contact, and the contact patch arc's toward the bottom.

 

[Vexy]

I hope you aren't trying to squeeze more shims in there with the stock thick ones already in there. Those stockers added together are the total thickness, which should not be altered. To move the carrier closer/further away, you need to add a shim to one side and subtract from the other. To subtract from one side you will need to replicate the thickness of the stock big shim with your aftermarket ones, allowing you to add/take away from that thickness.

So if you were trying to squeeze in a shim with the stock thick shims in place, that explains why you were ruining shims. If this isn't the case at all, well I just wasted a few minutes typing this up haha.
Good luck with your gears man. I'm setting up 4.56's in my 31 spline 8.8 right this moment as well.

 

[Captain Ledd]

I hope you aren't trying to squeeze more shims in there with the stock thick ones already in there. Those stockers added together are the total thickness, which should not be altered. To move the carrier closer/further away, you need to add a shim to one side and subtract from the other. To subtract from one side you will need to replicate the thickness of the stock big shim with your aftermarket ones, allowing you to add/take away from that thickness.

So if you were trying to squeeze in a shim with the stock thick shims in place, that explains why you were ruining shims. If this isn't the case at all, well I just wasted a few minutes typing this up haha.
Good luck with your gears man. I'm setting up 4.56's in my 31 spline 8.8 right this moment as well.

I've already solved that problem. I'm running different shims. Besides, the stock shims only work with the stock carrier.

I didn't run the new set of shims that came with it because they looked like they'd block nearly all oil flow to the special ARB bearing, The old ones were skinnier and more "open" I guess in the middle. But after asking around nobody knew anything about running special shims in theirs and they've been fine, so I used the replacement ones for this pattern.

Of course, I'm not sure how much time on the highway theirs spent with small tires. My application has to contend with thousands of miles of sustained higher RPM. (235/75R15)

 

[Vexy]

I've already solved that problem. I'm running different shims. Besides, the stock shims only work with the stock carrier.

I didn't run the new set of shims that came with it because they looked like they'd block nearly all oil flow to the special ARB bearing, The old ones were skinnier and more "open" I guess in the middle. But after asking around nobody knew anything about running special shims in theirs and they've been fine, so I used the replacement ones for this pattern.

Of course, I'm not sure how much time on the highway theirs spent with small tires. My application has to contend with thousands of miles of sustained higher RPM. (235/75R15)

Ah, I see now. I was unaware that you were running an ARB.

 

[4x4junkie]

I think that pattern looks good enough to run.

FWIW, I've noticed the 8.8 often seems to end up with better patterns at the tighter end of it's backlash range (which is .008-.015" BTW). You might try around .009-.010" maybe and see if the pattern cleans up any. If not, how you have it should be fine (you got good tooth coverage, even if it's not quite a textbook-perfect shape).

What brand are those gears? (just curious)

 

[Captain Ledd]

I think that pattern looks good enough to run.

FWIW, I've noticed the 8.8 often seems to end up with better patterns at the tighter end of it's backlash range (which is .008-.015" BTW). You might try around .009-.010" maybe and see if the pattern cleans up any. If not, how you have it should be fine (you got good tooth coverage, even if it's not quite a textbook-perfect shape).

oh ok then, the little pamphlet I got (I believe with the Yukon install kit) listed it as .011"-.016". A lot of what I've read has mentioned that you rarely end up with the "perfect pattern".

What brand are those gears? (just curious)

Ford Racing actually.

It's going on a daily driver and most places said that the Factory brand gears run quieter than others (no idea how true that is). Ordered my gears through Jegs, price was comparable to most other name brands, just ever slightly cheaper actually. I figured "Ford Racing" labeled gear sets couldn't be bottom end ones at the very least.

I suppose tomorrow I'll put the pre-load shims in and check it again. Hopefully it doesn't change much.

Almost there!!!

 

[4x4junkie]

.008-.015" is straight out of my Ford factory service manual.

I've always gotten much better patterns at the tighter end on 8.8s even using Yukon's gears. Not sure where they got their spec from

 

[Vexy]

What pinion shim thickness are you running? Just curious.

 

[Captain Ledd]

what pinion shim thickness are you running? Just curious.

.028"

 

[Captain Ledd]

New question.

I'm honestly starting to feel like I'm the densest person in the world when it comes to this.

1st question, Holding the pinion flange still while you're torquing it down to 140/150 lb-ft. What do you use to hold it still? Nothing covers this aspect, it just says "crank it down!". I just bent my rather large bolt in half (yes, I've gotten it out already). I'm about to look into having a special bar made tomorrow.

2nd question, my solid pinion spacer kit didn't come with any kind of instructions. The only thing internet searches brought up was "what about using one?", with the answer being "yeah, they're super easy!". I've been cranking and cranking on things and didn't realize (until it was too late) that it was pushing the spacer past the unmachined part of my pinion. needless to say, I'm not even attempting to pry it off. Is there really a front and back to the thing? does it matter if it's likely backwards?

My spacer kit is a 2 piece design the larger ring is wider and has a recess inside so you can stack shims in it and put another smaller, not as wide, spacer int it. So the shims are contained inside this unit. Maybe I should post a pic? It doesn't look at all like what internet images give me...

This thing really is a pain in the ass.