Mmmmm, yummy! Birf soup!

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MaddBaggins

MaddBaggins

Remember the KnightRider!
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Well, I drained my front diff today for my usual oil change and I got birf soup! Ohh yeah!
Any way, I have the parts for a birf job, so if anyone in interested in hanging out and/or helping, I'll be doing a birf job next saturday 11/21, in my driveway.

I'm planning on swapping the outers to the opposite sides and I don't plan on changing the bearings. I changed those last time I did the birfs 5 years/50k miles ago.
 
Afraid to look at mine, haven't done so since the last gap run..Guess I'll have to rechurn up the spooge for this years deer hunt...

Put if off till March, and I'll be there..
 
MaddBaggins said:
Well, I drained my front diff today for my usual oil change and I got birf soup! Ohh yeah!
Any way, I have the parts for a birf job, so if anyone in interested in hanging out and/or helping, I'll be doing a birf job next saturday 11/21, in my driveway.

I'm planning on swapping the outers to the opposite sides and I don't plan on changing the bearings. I changed those last time I did the birfs 5 years/50k miles ago.
Click to expand...

Will you be using the new style inner axle seals?:hhmm:
 
MaddBaggins said:
Thanks for the link. What makes it better than stock? Will it never fail?
Click to expand...

[strike]Guaranteed not to fail if it does Earthromer LLC is providing the warranty just send them the bill for replacement cost and they send you a check. [/strike]




What makes it better-

Indexed lip ensures a perfect perpendicular installation
Wide design allows movement, maximum shock absorption
Steel Expansion Ring ensures true circular inner dia
Seal holds to axle even under heavy vibrations
164% Increase in effective sealing deflection distance
89% Wider than the "common aftermarket seal"
 
I think it has a double wiper or something. Search it in the 80 forum, I seem to remember some write-ups.

EDIT: What Phil said.
 
zanyzonies said:
do you use Long Fields, or stock birfs?
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Stock. Longs would be a huge mistake for a daily driver. Chromo withstands twisting forces better, but it comes with a price. They wear out real fast. I've heard reports of 50k miles or less for Longs. For a trailer rig, thats fine, but not a daily driver.
 
I have one of the new seals and will be installing it soon. Mine failed on the drivers side. I have a stock one on the other side and wanted to see how the new ones stack up.
 
MaddBaggins said:
Well, I drained my front diff today for my usual oil change and I got birf soup! Ohh yeah! ...
Click to expand...

Most birfs live in the knuckles, so no birf soup in the gear oil, that that would be diff soup!:hillbilly:

The knuckles don't have breathers and the axles don't run perfectly concentric, so it's normal for some moly to be pushed into the axle. All of them that I have had apart have had moly buildup in the ends of the tubes, I consider this to be normal and wouldn't reseal the axle only for this. I look for gear lube washing out the moly in the knuckles (birf soup) as a reseal indicator. IMHO moly in the gear oil = normal, change the oil more often, gear oil in the moly = knuckle reseal.

How much moly was in the oil? When was the last gear oil change? How is the grease level in the knuckles?

My thoughts on the Marlin seals:
IH8MUD.com - View Single Post - Marlin Crawler inner oil seals and installation tool
 
Tools R Us said:
Most birfs live in the knuckles, so no birf soup in the gear oil, that that would be diff soup!:hillbilly:

The knuckles don't have breathers and the axles don't run perfectly concentric, so it's normal for some moly to be pushed into the axle. All of them that I have had apart have had moly buildup in the ends of the tubes, I consider this to be normal and wouldn't reseal the axle only for this. I look for gear lube washing out the moly in the knuckles (birf soup) as a reseal indicator. IMHO moly in the gear oil = normal, change the oil more often, gear oil in the moly = knuckle reseal.

How much moly was in the oil? When was the last gear oil change? How is the grease level in the knuckles?

My thoughts on the Marlin seals:
IH8MUD.com - View Single Post - Marlin Crawler inner oil seals and installation tool
Click to expand...


Normally I change my diffs every year, but this last change is from nearly 2 years ago. I've never had moly in the diff oil before and I got some chunks when I drained it. I planned on doing the birfs next year, but since I see an issue and I have the parts in the garage and the weather is going to be cool next weekend, I might as well do a birf job.

But then again, I may blow off the job until later, cause I'm lazy and I might come to PHX next week for the meet on friday.
 
MaddBaggins said:
Normally I change my diffs every year, but this last change is from nearly 2 years ago. I've never had moly in the diff oil before and I got some chunks when I drained it. I planned on doing the birfs next year, but since I see an issue and I have the parts in the garage and the weather is going to be cool next weekend, I might as well do a birf job.
Click to expand...

I have always seen moly, the front axle lube darker than the rear. IMHO some moly is normal, even good, it's a good lube. If run too long it will become excessive, thick lube will aerate, reducing effectiveness.

I change gear oil and top off moly in the knuckles to about 1/2 full just before Cruise Moab every year. Checking the grease level in knuckles is the most important part, the seals are designed to seal oil out, not very effective in the knuckle to axle direction. As long as oil isn't significantly diluting the moly in the knuckles, I don't see the need to reseal.

MaddBaggins said:
But then again, I may blow off the job until later, cause I'm lazy and I might come to PHX next week for the meet on friday.
Click to expand...

:cool: your not bringing that Ross guy right?:hillbilly:
 
-Spike- said:
I think it has a double wiper or something. Search it in the 80 forum, I seem to remember some write-ups.

EDIT: What Phil said.
Click to expand...
Howdy! I just installed the Marlin Seals in my Piggy. While I don't have any miles on them yet, I was very impressed with the design. They have a much wider seal area where they contact the inner axle, and the seal is part of an accordion sleeve that is able to "float" with the inner axle if it is bent or off center. They were under $10 each, and got here in 3-4 days. John
 
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