check my regear pattern, thoughts?

[zakt]

regearing the D30 in the front of our jeep wrangler for my first practice (used gears)... have had the carrier out 7 times at .007 backlash (6-10) recommended. Pinion depth 0 (marked on pinion, and old was the same). Thoughts on the pattern ??

[70_F100]

Looks to me like the pinion is set too deep.

The pattern should be closer to the center of the teeth on the ring gear.

What gauge did you use for the pinion depth? Keep in mind that even though the gears might be marked the same, changing the inner pinion bearing can have an effect on pinion depth.

[zakt]

I have 0 shim in it now for depth, in the yukon kit the oil slinger is actually thinner than the stock one so that could pull it alitle closer to the housing. Using new races and bearings but for set up using the inner used race (shim is under the inner race for depth, dremmel the OD down to slide in and out)

[70_F100]

I have 0 shim in it now for depth, in the yukon kit the oil slinger is actually thinner than the stock one so that could pull it alitle closer to the housing. Using new races and bearings but for set up using the inner used race (shim is under the inner race for depth, dremmel the OD down to slide in and out)

For several years, I worked at both IH and Jeep dealerships, and during that time, I built more D30's and D44's than I care to remember. I've also built power dividers and rears on tandem-axle trucks along with differentials from heavy off-road equipment.

A zero mark on the pinion does not mean zero shims.

Proper setup of a ring and pinion based on markings by the manufacturer is based on using a special tool setup that measures the distance from the center of the carrier bore to the face of the pinion. (Actually, the tool has two large round inserts that bolt into the carrier bearing bores and there is a shaft that goes through them. Then, there is a spring-loaded tool that is used similar to using an inside mike, except that once the distance is determined with the tool, a large mike is used to measure the overall distance of the tool.) The markings and correct pinion depth are determined when the ring and pinion are matched up at the factory (hence, the name "matched set"). On a used gear set, these markings may or may not produce satisfactory results. And one thing for sure (but you probably already know this), you never want to use a ring and pinion that were not factory matched.

Now, if I understand this right, you say you have a spacer/shim under the inner race. You also say that you installed new bearings and races. If the shim is too thick under the race or if either the bearing or the race are not completely seated, that would put the pinion depth too deep into the ring gear.

One thing that you say that puzzles me, is that you're using a used inner race for setup. If you're trying to get the pinion depth set correctly, unless you use the race that will be permanently installed, you're accomplishing nothing. Any two given races may have a large variance in machining dimensions. A used race is even more likely to give a false reading.

I know you probably don't want to hear this, but since this is your first time doing this, I would suggest that you have someone work with you that is familiar with setting up a ring and pinion. No, it's not rocket science. On the other hand, it's not a job for a beginner. If it's set up incorrectly, you'll have excessive gear wear and a lot of noise. It's not like rebuilding a transmission or engine. You have to consider pinion depth, ring gear backlash, pinion bearing preload and carrier bearing preload. Any mistakes in any of these will provide a job doomed for failure.

Just my

[zakt]

yep know all about the pinion depth tool... I have no shim under the inner bearing race... so all it would be off is the potential thickness difference of the inner bearing race. So most likely a new race will be thicker even making it closer.. so with that the only possible way I see to get the pinion moved farther back is to put the thinner yukon slinger in. The problem is, I have no shim in the pinion to take out

[averagef250]

More backlash. Then move pinion towards ring gear if needed. That isn't a very clear pattern. When you roll a pattern you need some resistance on the gears. It makes a difference in the pattern and the clarity.

To add backlash to that stack .010" opposite the ring gear. Don't take any shim out of the ring gear side unless you cannot get the carrier in. This is where beginners always screw up. I've taught a couple kids how to set diffs up and they always have a hell of a time getting a carrier in with any preload on it. You want as much preload as possible. If you've never done diffy work before that usually means take what you think is plenty of preload and add .030". If you know what you're doing a 5lb deadblow will just squeek a carrier with proper preload into place.

I don't know what good a depth tool would do you. I find they just confuse people and are very unnecessary. Diff work is less about quantified measurements and more about that pattern and mostly how things feel. Pinion preload is all feel. Pinion depth and backlash are told by the pattern.

[zakt]

I used a piece of wood, didnt seem to work very well. I have heard put the axle shafts in and use the brakes... so what is the best way to put the load on for the pattern?

Have backlash at 7 and looks like (6-10) is acceptable.

[averagef250]

Put some resistance on the pinion yoke with one hand, turn the ring gear with the other.

See, you're stuck on that .006-.010. Get that out of your head. Get the pattern right then take a lash measurement just to doublecheck.

[zakt]

sounds good, will put some more shim on the non ring side and re check the pattern before messing with the pinion depth.

[averagef250]

Pinion first, then carrier. Anything you do to the carrier is null if the pinion is wrong. Pinion depth, pinion preload, carrier preload, carrier offset (backlash). That order.

Backlash is the simplest thing to set. You got your preload right and it's just taking shim from one side and add it to the other.

[zakt]

backlash at 8 so here is the new pattern tried to do a better job with that...

Thought it would be easier to read the pattern and of course Im sure with more experience it would be easier or become easier the more you do This one I dont have time to experiment with though in the jeep still and daily driver...My 72 sterling 10.25 is out and have all the time to experiment with what happens when you do what...

[70_F100]

The pattern is still too deep (too close to the carrier).

[zakt]

so are we saying pinion depth is bad then?

[70_F100]

IMHO, yes...

[zakt]

and are we saying remove shim, if so no shim to remove....