1st gear install, plz check pattern

1st gear install....

http://i92.photobucket.com/albums/l19/dennisgrimm/P9040536.jpg
http://i92.photobucket.com/albums/l19/dennisgrimm/P9040534.jpg

This is my first ever gear install and it has taken 3 days of painful learning. This is the 4th try at the pinion depth on my D30. What do you think? If you guys agree that it looks good I will go forward with the final installation tomorrow night.

Specs are:
Inner pinion shims .010"
Outer pinion shims .050"
RGS shims .044"
NRGS shims .040"
Pinion Preload 20 in.lbs
backlash .0065"

Right now I have enough carrier shims such that it is snug. How much do I add to each side for preload?

Looks like you need more pinion depth to me, but my eyes are kind of fuzzy tonight. I add another .010" and see what that looks like. Only add .005" to your preload shims on the pinion and that should get you back into spec on it.

Mix a little gear lube into the marking compound and don't put so much on. Coat it just enough to cover the tooth up. Get a pick with the residual pattern too.

Also I don't usually mess around with the pinion preload until I have the depth set. I run the pinion nut down by hand until I'm close to spec on the drag then check the pattern. After I have a pattern that I like I put in the shims or crush sleeve. For shims I usually put a pile of them on there then check the in and out slop. I subtract the slop +.005" and that is usually close.

I didn't take pics of the last couple tries at the pinion depth because they were obviously wrong. I have tried no inner shims and that was obviously too far away and I have tried .020" and that was obviously too close. When I tried this setup at .010" it looked a lot better.

Too far away still? I will have to try at .012" or .015".

Thanks for the opinion, I live in the middle of nowhere and don't know anyone with experience regearing.

+1 for pinion too shallow. Even one thousandth can make a big difference in the pattern, in my (limited) experience. Divide and conquer by doing .015" first, then .013" or .017" depending on the pattern, then .012", .014", .016", or .018" depending on the pattern.

I used about .010" of preload (beyond zero-end-play) on both my D30 & D35 carrier bearings for the final install.

BTW, when you check the pattern, are you doing it with some resistance on the carrier? (for example, with axles/drums in and the e-brake on) That will give the easiest-to-read pattern.

Ok, I hear ya, it is too shallow. I will increase the inner pinion shims and reread.

When you say +0.010" beyond zero play for the carrier do you mean .005" per side or 0.010" per side?

Yes, I am applying rotational resistance when checking the pattern. I am probably using too much gear marking compound.

Thanks guys!

Pattern dosent look too bad. But how is your backlash?? When setting your pinion preload I use this methood instead of going by what the book says st it to 30in pounds resitence new and dry then tap both ends on the pinion make shure it;s set check it agin. Everyone here says 30 is too tight but beleve me it losen up as soon as you drive it if you set it too loose it'l get sloppy. Too tight is also bad however it will seize. Buy one of those cheap 3/8 drive bar type tourque wrenches at sears.

I don't know what you mean by "inner shims". Are these the small shims that go between the front and rear pinion bearings? If this is what you are calling the inner shims, take them out until after you have the pattern set. You tighten the pinion nut until you get a reasonable amount or rolling resistance to mark the pattern.

The only shims you need in there to set the depth are the shims between the rear pinion bearing race and the casting. This is how you set the pinion depth. As was said earlier, I would add .010 in front of that race and mark it again. You will probably end up at .004 to .006 deeper than you are now.

After you change the depth, you obviously set the backlash with shims. The FSM says to add .004 to each side for carrier bearing preload.

I just finished my Dana 30 and ARB locker this weekend. I had to pull about 8 patterns to get mine right, so I feel your pain.

traitor,
Backlash was bang on (see first post) at 6.5 thou. I have a nice dial type in-lb torque wrenches for measuring the pinion rotational resistance. I will try tapping the pinion to make sure it is seated.

MoFo,
By "inner shims" I meant the big ones that set the pinion depth. The pics are at .010" for pinion depth shims. I have tried .020" and that was too close. I have tried no dpth shims and that was too far. That is why I tried .010", split the difference. The way I read the pattern was ok, maybe not quite deep enough. That is why I am going to try .012" for pinion depth.

I am checking my pinion preload with setup bearings (old) and they are oiled.

I am working like this:
1. adjust pinion preload till it is on spec
2. adjust backlash
3. paint the gears and read the pattern
4. if the pattern is good I am done, if not good I adjust the pinion depth shims and go back to step 1

You don't need to set pinion preload until after you get the pattern right. Just pull the nut down till you get some rotational resistance.

I have never seen or heard of one setup with a shim pack that thin. Did you put in the oil baffle yet? That goes in front of the bearing race, along with the shim pack. The baffle is usually .018 to .020 thick. If you did not include that with your above shim pack thickness, then that would make the total .030 to .032, which is closer to what I would expect.

I am not using the oil baffle for two reasons.

1. When I tore apart the original setup I managed to screw up the oil baffle beyond repair. Reading the writeup on pirate it seems to indicate that the oil baffle isn't nessecary and it can be compensated for in the shim pack.

2. The origional setup had a baffle but NO pinion depth shims. This confused the sh!t out ouf me because being my first regearing I was trying to figure our where the large shims go. I eventually figured it out and now I think that even if I wanted to use the oil baffle I can't because I need less than .020". This is thinner than the oil baffle. Is it possible I have an extra thick slinger?

I am not the first person to be without depth shims.
http://www.naxja.org/forum/showthread.php?t=91203&highlight=pinion+depth+shim

I have searched all over the place and can't find a straight answer as to wether I need the baffle or not. Like I said, the article on pirate4x4 seems to indicate that it is optional.

I agree so far that depth is too shallow. I won't add to the discussion on that. I didn't use my oil baffle on either axle. My new D44 one was huge and actually blocked the port. I didn't use it on my D30 either.
Not every axle is the same. You would expect the housing to have room and make that up with shims. I actually have no pinion depth shims on my D44. I didn't need to go "out" more so I was ok, but I couldn't believe I didn't need any! So not every shim pack is going to be the same.
BL is between 6 and 10. 8 is in spec, but 8 is dead in. Many I have talked too feel as long as it in spec to go with it. However, if you hit 6 or 10, then adjust it.
Last, but not least, setup bearings only get you close. They are good to use and save a bunch of time with initial setup, but when you do final, everything will change. Get as close as you can, but don't get obsessed with perfect. With my final rear setup, I had to adjust once. With my final front I had to do it twice. Patience is a good thing. Less compound, more drag. Use a rag. Later.

Low pinion diffs don't use the baffle, High pinions do. It's to help keep the gear oil up in the pinion bearings.

I agree that your pinion is still too far away.

dennisgrimm said:

When you say +0.010" beyond zero play for the carrier do you mean .005" per side or 0.010" per side?

Click to expand...

I did about .05" on a side.

Yes, I am applying rotational resistance when checking the pattern.

Click to expand...

I would apply as much as possible (a helper is great here to hold a tire or whatever); it really makes the pattern come out fast.