Project B2R

[mjonesjr]

Having the drive that shallow will cause your ring gear to chip. That is way too much stress at the end of the gear IMO.

 

[Bray D]

The shape of the drive pattern looks good, but it does look a bit tall on the tooth. Coast pattern looks to err on the deep side, which is interesting after seeing the drive side. Is this pattern consistent at different locations on the gear? How are you applying the load to get the pattern?

I turn the carrier with one of the ring gear bolts. Works pretty well. Run a couple full revolutions and look at the pattern all around the ring gear.

 

[Maverick]

I'll check the pattern in a different spot. I load it by holding a rag firmly against the ring gear while rotating the pinion gear.

*EDIT* The pattern looks the same on other parts of the gear. Not sure what do at this point. When I add shims to move the pinion in closer it totally screws the pattern up.

 

[Bray D]

Try the method I described. I think you'll be pleased. It's quick and effective.

I'll paint up 3-4 teeth in 3-4 locations on the ring gear then spin it a few revolutions in both directions. Sometimes it helps to look at the teeth that don't have paint directly applied to them - they may show a more defined pattern.

 

[Maverick]

The pattern does looks better on the unpainted teeth. For some reason it doesn't look so far towards the top of the gear...

 

[Bray D]

I would probably run it as long as there's SOME paint between the pattern and the top of the tooth. Be sure to preload the carrier bearings pretty good to fight against ring gear deflection under load.

Dana axles always piss me off because when I go from the setup bearings to the final assembly bearings, the pattern changes slightly. Never enough to matter, but it does a little bit. Always does for me anyways. It's frustrating.

In the end it's your decision man. Maybe some other guys will chime in with suggestions. I wasn't as concerned with my frontend as I was my rear, knowing that it would mostly only be used for low speed stuff and far less frequently.

 

[Maverick]

I was reading up on carrier bearing pre load. Seems like the you get the back lash set correctly then add anywhere from .003-.005 to each side to pre load carrier. Is that how you do it?

 

[Bray D]

Yep, exactly. It should require a few good whacks with a dead blow to seat the carrier if you don't have a case spreader.

 

[Maverick]

There is just a hairs worth of paint on the top of tooth, which is as good as I've been able to get on this gear set. This is only my third gear set up though, so I don't have a doubt I could be doing something incorrectly. Like I said moving the pinion in towards the ring threw the pattern way off. It did center it up better between the root and the flank but the drive contact patter was small and towards the toe while the coast was equally as small and all the way out to the heel. Not sure what else to do besides call it good and run it. I wonder if the cryogenic treatment I had done has anything to do with it

 

[-Nathan-]

I personally wouldnt run that pattern. You will see broken ring gear teeth in the future. I 100% agree with Bray. Every time I setup a Dana axle using my setup bearings, and the pattern looks perfect, when I swap out to the real bearings it changes just enough to piss you off. And yes, for carrier preload I get it to where I want to, than add .003-.005" shims to each side, and whack it in with a big rubber mallet, or dead blow hammer.

Also, are you applying load when you run your pattern? simply turning the carrier is not enough, there isnt any load on the pinion. You have to either have a buddy hold the pinion with resistance while you spin the carrier, or vice versa. Without a load on the gears, your pattern will not be accurate.

As much of a pain in the ass it is, take it apart and mess with your pinion shims some more, I think your pinion is a bit too shallow, its not worth messing up a set of gears and bearings later on.

 

[Maverick]

Yes I'm applying load to the ring gear, I'm not that much of a newb. I'm going to pull it back apart tomorrow and mess with it some more.

 

[Maverick]

The first pic I posted is with .013" thickness shim on the pinion. Here is what happens when I start moving the pinion away from the ring, this is at .016" thickness.

Drive:

Coast:

The pattern gets smaller and moves in toward the toe on the drive and the heel on the coast. It only gets worse I as I go up in shim pack thickness. I went in small increments all the way up to .027". I check the B/L every time, load the gear, clean the teeth, blah blah blah... Here is the last pattern I just ran at .014"

Coast:

Drive:

What say y'all?

 

[Bray D]

Try spinning the ring gear instead of the pinion. There's no need to add external load if you do. The force required to accelerate the pinion from a dead stop to 4x the rpm you're spinning the ring gear at is enough to make a good pattern. This is what I ended up at with my d44.

I don't really know what to tell ya man. You know as much as anyone it's a game of guess and check. Just keep playing with it until it's good enough that you won't lose sleep at night.

Looking at it, it looks like my pattern was up towards the top of the tooth as well. I've more than beat on my gearset (broken hubs and a chromo shaft) and it's held up fine.

I'm not too learned on the cryo process and its effects on the material. It may have done something, but I wouldn't bet on it. It's used quite a bit on gears if I'm not mistaken.

 

[Maverick]

I got it all buttoned up about a half hour ago. I'll post up some pics tomorrow, I happy with the pattern I ended up with. I tried so many different set ups today that I'm confident I came up with best pattern attainable for the gear set. You were right about the pattern changing going from set up to final install bearings, but it actually changed for the better in my case.

Even though I'm done with the install, I'll try your method tomorrow of spinning ring gear instead of the pinion. I'd be interested to see if it makes a difference.

 

[Bray D]

Good deal. That's pretty much it, try every combo possible and narrow it down to the best pattern attainable. I'm glad you got it wrapped up.

I'm also glad you're back to workin on the rig. Keep the momentum going!