So after weeks of tracking down parts and waiting for them to arrive I started putting my front hubs back together.

I used Timken all around, and I've found the the inner bearing (387A) doesn't slide onto the spindle.

The diameter of the spindle is 2.25" at the bearing surface.

But the bore of my bearing measures 2.10".

Is the fifthteen thousandths due to the bearing being cold? It's only about 45*F around here.

What do you think?

 

I had the same issue both times I've rebuilt my axle. Tried multiple brands and ended up concluding it was my spindle, but I've since ran into others with the same issue of the same bearing. I believe it is a manufacturing issue, only thing i can think if. Its a big difference, but you may be able to heat the inner race of the bearing up enough to get it on. \

 

I've got the hub sitting inside with a small heater on it.

How did you end up getting the hub back on? Taking a torch to the bearing doesn't seem like a good idea. Lol...

This whole project has been a PITA. From finding correct parts to having idiots send me the wrong parts multiple times to *******es who assembled the axle for the PO and installed the parts backwards or not at all...


The trucks been on stands for nearly a month. I'm pretty fed up.

 

Just realized that wouldn't work as the bearing had to be in the hub, so never mind my previous comments lol.

 

What are the specs on your truck? F350 or F250? 4x4 or 4x2?

 

F250 - 4x4

I let the hub sit inside with a heater on it for an hour. It got nice and toasty and still no dice.

 

Yeah, I doubt you'll make up .015" difference in temperature. Let me do a little digging and see what I can find.

 

It almost has to be an issue with the wrong bearing. Timken lists the 387A as having an inner diameter of 57.15mm which equals 2.25". If you're seeing that much less than that, I'd say you have a bum bearing.

Here, check it out.

That's disconcerting, to say the least.

 

Yeah... I looked up the spec sheet right after I measured the bearing and spindle.



Makes you wonder how the bearing passed QC being that far out.

I guess now I get to wait another week for a new bearing...

 

That sucks. Is there not a NAPA or something close to you that carries Timken bearings? I'd sure feel better about getting another one if I could measure it first.

 

Something sure doesn't seem right. I've never run across any bearing, much less a Timken, that's 0.015" out of tolerance. I think the tolerance for the bearing fit is supposed to be in the order of tenths of a thousandth.

Makes me wonder if it could be a counterfeit. Or, just the wrong bearing, is the part number clearly engraved or etched on it?

Really frustrating. I wouldn't try to make it fit, 0.015" is way too much interference fit and something will go wrong.

Bob

 

My thought exactly. A counterfeit, maybe. Although it looks pretty legitimate and yes, the correct part number is clearly engraved into the bearing.

I bought these bearings from RockAuto, and wondered about their legitimacy after noticing the price. $9 for a bearing you pay $20 for someplace else?

 

That kind of discount isn't unusual at Rockauto, and I've never gotten the wrong bearings from them in the past. Did the packaging look legit?

 

Take some pics of the bearing and box and such, and zap them off to Timken, I'm sure they would be interested.

 

+1 And also I'd contact Rock Auto to see what they have to say. I've never had a problem with anything I've got from them and they should be informed about this problem. If it's a bad batch of bearings, you may at least be able to save some other guys the same headaches.

Bob