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2.25 Diff Gear (AE #6580) I wonder if there has been a new moulding run or something???
Picked up a couple new 6580's from tower the other day.
Built up new gear, new ceramics, new rings, the works....right?
(I really DIG those ceramics! Buttery smooth, nice tension)

So I get done with my bearings and stuff (always a good opportunity to make sure the bearings are clean and good-to-go)...
Slap my outdrive bearings on, reassemble the case.....

And notice that I have a binding issue...but it has nothing to do with topshaft, idler, or bearings...

I notice binding, take all the gears out, check the outdrive bearings really good...they're silky smooth, just cleaned & lubed.
Check the topshaft and idler inside and out...both look fantastic...bearings, install and they're smooth as silk as well.

So I take the diff, and install it by itself and yep, sure enough, there's some scrub/binding/SOMETHING going on. It was late, I was getting kind of aggravated with the situation... Through the years I've never had that happen with an AE part.

I'm wondering if anyone else has run across this in their builds/rebuilds with a new diff gear recently?? Maybe they had a bad run or something. Just tossing it out there to see.

I'm going to eyeball it with magnifying glass tonight, see if I can find exactly what's up.
Got the digital calipers showing 24.83mm diameter and 9mm wide for the gear. That sound about right?
I haven't gone around with the calipers to see if the entire width is all 9mm to check for variances yet, though.

I don't know per experience, but hows the center hole? I don't think it would spin true if that was off or needed cleaning up with an xacto.

Well, after tearing it down and rebuilding it a couple of different times tonight just to make sure I had dotted my i's and crossed my T's...

That center hole may be off just a hair....I mean a hair....but it is enough to make it non-useable.

Luckily I had ordered two when I did...and the second one is spot-on perfect. Silky smooth, no binding, silent speed.

Guess I received an odd-ball, which, in my little experience, is pretty odd. Chalk that one up as my one rare oddity of an A.E. product not being right.

Oh well, it's only a $2.50 gear, thank goodness.

Sure had me puzzled there for a while, though.

A lot of Associated parts seem to have poor manufacturing tolerances lately. I've had more poor-fitting parts in my SC10 kit than I have in cars and trucks and random parts from the previous 20 years. I've been so frustrated I haven't even run it yet, may never and just get rid of it.

Claymore5150 wrote:Oh well, it's only a $2.50 gear, thank goodness.

Call them and let them know; if we keep letting stuff slide then they will not know to improve their quality control.