Technical Two axle seals?

I'm rebuilding the differential on my 49. It's a Ford 9" from a '57. Ranchero. I pulled the seals (or so I thought) and behind them is what looks like a second seal.

Here's the driver's side seal that I pulled (click to enlarge):


And here's a shot of what's behind it:

Am I right in thinking that that's a second seal? If not, what is it?
If it is a second seal, is it common practice to have two seals?
Do I need two seals?
Can I take this 'second seal' out and just use one?

Thanks for any advice

 

Looks like some monkey business going on there...maybe the last guy didn't put it together right?

Did you check to see where both seals ride on the axle? and what size they are vs the axle diameter?

 

Squirrel is right.Car companies are cheap.They aren't going to over build anything.The last guy is more than likely the culprit.

 

Different nine inch use different seals. Both are correct but not used on the same rear.

 

Most nine inch rears that I have rebuilt have both an inner seal and outer. Your parts house should have them both and yes I would replace them both, there not expensive.

 

Never ever saw that...Not in the seal listings either..??

 

Yeah seen it before.As Squirrel and Bob say,check your axle,probly has a tiny groove worn into it.Some guys just put two seals in to stop a leak or are wrong size etc

 

Don't they use a sealed bearing and no seal on the axle? I thought only the WER axle, with the rear cover and clips that hold the axles in, used seals on the axles.

 

I thought the 9" 59' rear I got for my Comet was a wer...No rear cover or c clips though..The parts man gave me hell as it was the odd ball in the bearing size and he had to order them...

 

I'm not an expert but here's a pic of one of the original axles and I believe this is a sealed bearing:

I'm not sure what a WER axle is even after googling it :-(

 

Sealed rear wheel bearings usually have an O ring on the outside of them, to keep the oil from seeping around the outside. So I'd say that's not a sealed bearing. They also have a rubber seal on the side of the bearing that is "up" in your photo.

The seal should rid on the shiny, smooth round area just above the lock collar. Did both seals ride there? or only one?

 

WER might be here

http://www.fordification.com/tech/rearends_ford06.htm

 

Just took two '57-'59 9" rears apart, one big bearing, one little bearing. Both housings only had one inner seal. Kinda leaning towards the idea that someone added an extra seals at one time so it would ride on a virgin area on the shaft. Used to double seals on a regular basis on pumps, etc with worn seal areas.

 

A 9" with ball bearings like you have should have a single inner seal. The bearing will not have an o-ring on the outside even though it is a sealed bearing. The inner seal stops the oil from leaking around the outside of the bearing.

The later style 9" with tapered roller bearings have an outer seal that drops on the axle before the bearing is pressed on. Those housings usually are not machined for an inner seal and they should not have one because the TR bearing is lubed by the gear oil. I only mention them because I have seen basket cases where people have tried to mix ball and roller bearing axle parts and get into all kinds of mismatches.

 

The WER axle doesn't have a drop out carrier. The roller bearings are pressed into the ends of the housing followed by a seal and the rollers ride directly on the axle. When a bearing goes out, it ruins the axle. C-clips on the inner ends of the axle keep the axle from coming out.