Aluminum debris on gearbox filter - Is this an issue?

Change the bearings on both sides. Looks like you caught it just before it blew up. There are some bearings located on the back side of the middle bearing block you have pictured. You need to remove that to get to the bearings on the back side of it. Looks like the bearing cage/s has/have had it. You won't know the full extent until you pull off that mid block. The reason you are seeing the metal bits on the filter is because the damage is on the side facing the gears, and the screen caught the bits and didn't pump them through the gearbox. So.......finish pulling off the cover on the left side of the box.

 

One more thing.

Be VERY careful when you go to remove the plastic clip on the tip of that shaft, just in front of the phonic wheel. Not the snap ring the little gray one in the groove. If you aren't careful you'll snap the little "hook" off and you'll have to get a new one.

And

Two of the ring nuts get removed counter clockwise.

 

Excellent post and information, Ernie....

You're the best...!

Mike

 

What I'm saying is that a bearing/s cage is on the way out or has actually given up the ghost. The aluminum shavings are coming from lateral movement of the main or lay shaft, or both. My guess is that it's the bearing on the main shaft, the oil pump side, as that seems to be the one that likes to go. When the bearing cage gets loose it lets the shaft move either left or right, and the the end of the shaft will start to act as a lathe and cut into the cover. At least that's what it did on mine. Check to see what the tranny oil pump looks like, it's inside that first cover you took off the left side. There are also some small bearing retainers that are screwed to the inner sides of the gear box, in the middle of it, about the diameter of a dime. My bearings blew out so bad that it chewed into one of those also, then sent the cage through the box and destroyed the ring and pinion = BIG $$$$.

The aluminum shavings are telling you there is something wrong, don't ignore it. Because right now you are only looking at a couple hundred dollars for some new bearings. If you let it go and that cage comes apart, then goes through the tranny, you are looking at many thousands, to tens of thousands to fix the tranny, depending on how many gears get destroyed and which ones.

So........

Remove the phonic wheel, remove the ring nuts, and then get that center cover off. Once you have it off turn it around and look at the bearing on the back side, the side that was facing the gear box. Then look around inside the box to see where the aluminum was getting widdled away from.

There is something wrong and those shavings are the canary in the coal mine. So keep diggin till you find the problem.

As for sourcing the bearings, just take your old bearings to a bearing shop and have them get you new ones. I can still the the SKF factory numbers on yours, so it shouldn't be a problem.


Or, since you are in LA, if you want we can take your box to fatbillybob's and have another gearbox Stooge session next week.

 

Before tearing it down, maybe you should check the runout on the main and lay shafts just to make sure you're not seeing casting burrs. (I would never contradict Ernie on gearboxes, tho)

 

LOL!!! Smartass

It's actually fatbillybob you don't wanna cross when it comes to the gearboxes. And I don't ever question him.

Hahahaha!

 

Actually Bruce's makes a good point.

However.

My thinking is this.

Since you have it this far apart already, it's just a few more bolts to get to the back side bearing, and you can't really know about those bearings until you take off that center block off. The outer ones can look okay, but the cage on the inners can have had it. It's just better to take the extra time and know for SURE, than guess, and guess wrong. You my find that they are perfectly okay, and that it is as Bruce says, casting bits. But you won't truly know until you have a look.

Again, you already have it this far apart, so it's not like it's that much more work.

BTW: Nice job on taking it apart.

 

Good man!

Actually it looks like you have the upgraded bearings in yours. What SFK part numbers do you have on the bearing race? Get the same ones.

Hows the inside of the box look? Anymore aluminum bits? Can you see any signs of wear?

When you go to put it back together, fatbillybob mandates that you use Loctite 271 on the treads. And for between the intermediate block and the case I used Hondabond HT to seal things up.

 

I'm not 100% sure on this, but I think the bearings you show in the picture are the "upgraded" bearings. The reason I think this is because when my bearing went out it was the one with a the grey cage. The cage is what came apart in mine and destroyed the gears. So since the one you have pictured does not have the cage I'm assuming it's the better version.

I would really look to find the ones you have in the gear box. I have had pretty good luck finding bearings I need from Applied Industrials http://www.applied.com/. Give them a call, or find a shop near you and take your old ones with you and have them match them up. They will probably have to be ordered.

 

It's not at all uncommon to find "chips" in the gearbox or differential cases (even engine blocks) from any manufacturer (even Ferrari / ZF). These are pieces of metal, either aluminum or steel (depending upon the case material ---- aluminum in this case, of course), removed by machining operations during fabrication. These will resemble "pencil shavings" which look exactly what you have in your photo.

Although, the cases are cleaned out after all the machining processes, and prior to assembly, often some pieces get left behind. They don't cause a problem, especially if aluminum as the "machinery" (gears, etc.) can simply chew them up if they do get into anything (which they almost never do as they tend to get tossed away from the action or to settle in the bottom of the oil chambers), and will eventually get collected and removed through subsequent oil drains / changes.

I've found them in nearly every make / type of vehicle, that I've ever drained. Depending on how many chips were left behind initially and where they end up hiding, it can sometimes take quite a few miles and many oil changes to get them all out. Of course, when doing a tear down, such as you are, you have a good opportunity to get them all cleaned out in one shot

So, if you don't find another possible source, such as anything damaged, after thorough inspection, I wouldn't worry.