I have a very simple question about gear pattern and backlash, you set gear pattern with spanner nuts them you set backlash with dial indicator and spanner nuts, does that change gear pattern to any to any extreme, Thanks,Mike
The spanners set back lash and the side bearing preload . The gear pattern is the pinion depth . When you say pattern,,I ***ume you are meaning the ****m layout fluid on the teeth ? That is a simplified answer . Tommy
The crush sleeve is to adjust the pinion bearing pre-load and that's all it does. The pinion/yoke nut is tightened until you achieve the recommended pre-load (turning force of 8-17 inch-lbs on used bearings, 17-27 on new ones), then the pinion depth is adjusted with shims between the case and the pinion bearing retainer. Some vendors use select-fit solid spacers rather than a crush sleeve. Once pinion depth is close, the final gear pattern is adjusted with the side adjusters and possibly a different pinion shim. Different pinion shim thicknesses are available.
to elaborate on this...the pattern is adjusted with the pinion shim. The side adjusters set the backlash and side bearing preload. They don't really adjust the pattern, if you set the backlash correctly. a bit more info here, and I expect there are lots of confusing youtube videos to watch, as well. http://selectric.org/manuals/rearend/indexford.html good luck, it's fun, but does require some tools/equipment that you might not have.
Ford couldn't quite seem to fully make up their mind on the pinion bearing pre-load. Depending on the year of the service manual you look at you can find slightly different numbers. The max numbers seem to be fairly consistent, the low end can vary by a couple of inch-lbs either way... The tool most guys lack is a low-value inch-lb torque wrench for setting the pinion pre-load. You can't use a click-type, you need a dial (best) or beam type and it has to be pretty accurate. They're also not cheap...
No, not exactly. The pinion bearings preload is adjusted by partially crushing the ‘crush sleeve’. Unless, as some builders choose to do, the crush sleeve is replaced by a spacer and select fitting shims to achieve the preload specified. Think of the crush sleeve as an ‘adjustable’ spacer between the pinion bearings. It can only be adjusted one way though…..thinner/shorter. If you overtighten the pinion nut and crush the sleeve too far, resulting in excessive pinion bearing preload, you must replace the crush sleeve and do it over. A spacer and selected shims, when correct, stays correct and allows the pinion flange to be removed to replace a pinion seal, for example, and retighten the pinion shaft/yoke nut to it’s proper tightness without affecting the pinion bearing preload because the fixed length spacer does not ‘give’ (compress) when the nut is tightened. EDIT: my explanation above only applies to pinion bearing preload…..NOT adjusting pinion depth, which is a separate thing, very ably described by @Crazy Steve in the post following mine. Ray
No, the crush sleeve is just to set pinion bearing pre-load. Once this is set right, all pinion shimming for pattern is done with various-thickness shims between the pinion bearing retainer and the main case.
Just a clarification since shims were mentioned for two separate operations: Pinion bearing preload is adjusted by either a crush sleeve (most common), or a spacer and shims (performance application where rear may need service on a frequent basis). Pinion depth is changed by the shims between the pinion bearing carrier and the housing. No need to disturb the pinion preload to change pinion depth.
As the others have said the pinion bearing spacer (crush sleeve or solid spacer w/shims) sets the bearing preload on the pinion. I always use solid spacers. The pinion shim is used to set the depth of the pinion relative to the ring gear.
The Nine inch Ford rear end is a very forgiving rear end. I have seen nine inch pinions that you could move up and down a lot and the rear end would not make any noise or whine. I have set up a lot of nine inch and to me the factory pinion preload is a lot! I tend to set at the lower end. Addressing the “ clunk” it is usually contributed to slack in the spider gears and axle splines. If your gears are far enough apart to “ clunk” you will have other problems! Bones
The best way to set the side adjusters is to set the carrier in the housing with the pinion in place. Take all the play out of the side bearings with the ring gear away from the pinion (lots of backlash). Turn the adjusters equal amounts, one in one out, until you just have zero backlash between the ring and pinion. At this point you have all of the play out of the carrier bearings, but no preload and zero backlash. You can now lock down the outer adjuster. Use the inner adjuster in to get the proper backlash. That will also set the carrier bearing preload. The adjuster will get pretty hard to turn the last little bit. Now you can run a pattern and see if the pinion needs to be moved in or out. Changing a pinion shim will change the backlash so you need to readjust the carrier. You could do this by running the adjusters in and out equal amounts. However, I would probably just move the one that brings the backlash back in spec. It will give a little more preload to the bearings but it's hard to get too much preload on the carrier bearings. Also, if you look in a Ford manual they have a pretty broad range for acceptable patterns. Back in the late 60's early 70's I worked at a Lincoln-Mercury garage. Ford was having some problems with gear noise. Under warranty they wanted you to pull the 3rd member and run a pattern and adjust it to a more favorable pattern. It never cured the gear noise. In most cases it just moved the speed at which the noise came in. Only after doing this could you replace the ring and pinion. That was the real fix.
Seems as once the gears take a “set “ to make noise it has been really tough for me to adjust the noise out . The 9 in is very for giving , very easy to install new gears run quietly .
Wow, tremendous insight. Thanks for sharing your wisdom. I've built around a half dozen 9" diffs and the noisy one was incurable. "...a more favorable pattern...never cured the gear noise...replace the ring and pinion...that was the real fix." Su****ions confirmed.
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