Birf grease leaking from Steering Knuckle Studs (1 Viewer)

[Biff]

Ever since I installed a new diff. gasket the passenger side steering knuckle has been leaking birf greese, the drivers side is 100% dry. The greese is coming out specifically from the area around the knuckle studs. I have torqued all the studs to spec. and still keep getting this leak. Any advice on what I missed or what to do to stop the leak. I'll post a pic of the leak shortly. TIA

 

[clownmidget]

Do you have the oem breather or have you re-routed/extended it? Also, post a pic so there is no confusion about where/what you're talking about.
Was there any leaking before the new gasket?
When was the last time you replaced the inner axle seals and/or repacked the birfields?

 

[elmariachi]

The greese is coming out specifically from the area around the knuckle studs. I have torqued all the studs to spec. and still keep getting this leak. Any advice on what I missed or what to do to stop the leak. I'll post a pic of the leak shortly. TIA

Moly grease is generally too thick to seep through the lower bearing cap by itself if the studs are tight. My guess is you have some diff oil in the knuckle cavity (meaning failed axle seal) and that is thinning the moly and seeping out the bottom. This is, of course, provided that the leak is not at the bottom of the felt/rubber wiper seal assembly.

To stop it you must rebuild the knuckle and replace that axle seal.

 

[Biff]

This is a pic of what I'm talking about.

You guys really think its a seal, its that the case I must of screwed up one of the seals when I installed a 2nd diff. gasket after I did my birfs. I replaced the inner axle seal and re packed the birfs only a few months ago when I installed my ARBs. Only thing is that I had to go back and pull the axles due to a screwed up diff. gasket, since the seals were all new I reused everything.

 

[elmariachi]

You guys really think its a seal, its that the case I must of screwed up one of the seals when I installed a 2nd diff. gasket after I did my birfs.

IMO, the inner axle seal can only barely sustain one pass of the axle going back in after replacement. The fluid I see in this pic is golden brown, like diff oil. If the seal is leaking as I suspect, the fresh oil is coming past the seal, down the back of the knuckle housing inside the ball cavity, through the lower knuckle bearing and past the bearing cap. Pulling those axles back out the second time probably did it.

 

[Biff]

IMO, the inner axle seal can only barely sustain one pass of the axle going back in after replacement. The fluid I see in this pic is golden brown, like diff oil. If the seal is leaking as I suspect, the fresh oil is coming past the seal, down the back of the knuckle housing inside the ball cavity, through the lower knuckle bearing and past the bearing cap. Pulling those axles back out the second time probably did it.

Thanks Jim, I appreciate your thoughts on this. I knew I was risking a leak when I reused those brand new seals, now I have to pay for it. Now you think I can get away with replacing the inner axle seal on one side only or should I just do both.

 

[flintknapper]

Certainly looks like diff. oil. The only other possibility is that the grease you used to pack the birf. has broken down (not likely). When I did mine I was just starting to see what you pictured here.

In fact, I was a little surprised that the seal between the knuckles and the kingpins were nothing more than a machined surface (no gaskets). Maybe its a good thing, as it tends to point out trouble (like a weep hole in a water pump) and give you a chance to correct the problem before more damage occurs.

I noticed there seems to be an axle guide just inside of the oil seal in the axle housing to help keep the axle off of the seal during installation, but it would be real easy to damage one anyway. I lightly greased the entire axle shaft on mine before attempting to reinstall, I also put a little grease on the back side of the oil seal to help keep the spring in place.

Sorry to see that yours is leaking (another messy job).

 

[Biff]

Thanks guys, looks like I'm going to have to go back in there. This is what you get for being cheap and not using a new seal, going to cost me more now.

 

[Rookie2]

I don't know what you guys are looking at, but the grease I see looks red.

Did you use the exact same grease in both knuckles? What kind, Mobil 1 Synthetic perhaps?

Beno had something similar going on after his knuckle job. I believe it was determined that it's common that the synthetic greases will seperate and seep some.

Good Luck.
Rookie2

 

[flintknapper]

I don't know what you guys are looking at, but the grease I see looks red.

Did you use the exact same grease in both knuckles? What kind, Mobil 1 Synthetic perhaps?

Beno had something similar going on after his knuckle job. I believe it was determined that it's common that the synthetic greases will seperate and seep some.

Good Luck.
Rookie2

This is a good point. I noticed in two of the tubs of synthetic I opened that at the bottom of the tub there was perhaps a tablespoon full of separated oil. The other two tubs I used were fine. It might be worth waiting a little bit to see if the "weeping" stops. Mine have not leaked any to date.

 

[Biff]

I don't know what you guys are looking at, but the grease I see looks red.

Did you use the exact same grease in both knuckles? What kind, Mobil 1 Synthetic perhaps?

Beno had something similar going on after his knuckle job. I believe it was determined that it's common that the synthetic greases will seperate and seep some.

Good Luck.
Rookie2

I used the exact same grease, in both knuckles. Yes it was Mobil 1, syn. Rookie, do you agree with Jim, that it might be the inner axle seal, or should I not worry about this? Appreciate your thoughts.

Thanks

 

[OGBeno]

That looks red to me and I think that looks like M1...I agree with R2 on this one.

The M1 was used for the wheel & trunion bearings right Victor?

Moly would be much darker in color, and even diff. fluid would be much closer to a brown as opposed to a reddish tinted grease.

I assume Victor that you didn't pack the knuckle housing with M1

Is there any chance (and I really don't know the answer to this) that the trunion bearing could be weeping some grease below via pressure? Just a thought.

I hate to say this, but you might have to go in there if you are indeed worried about the weeping in that picture.

Good luck.
-onur
Akron, OH

 

[Biff]

That looks red to me and I think that looks like M1...I agree with R2 on this one.

The M1 was used for the wheel & trunion bearings right Victor?

Moly would be much darker in color, and even diff. fluid would be much closer to a brown as opposed to a reddish tinted grease.

I assume Victor that you didn't pack the knuckle housing with M1

Is there any chance (and I really don't know the answer to this) that the trunion bearing could be weeping some grease below via pressure? Just a thought.

I hate to say this, but you might have to go in there if you are indeed worried about the weeping in that picture.

Good luck.
-onur
Akron, OH

Actually I'm more curious than worry, the rig is not my dd so I can take my time with this and learn from my mistakes and from you guys.

Based on my research/work/and what you guys have told me I will be reopening the birf, repacking with molly greese, and replacing the inner axle seal, I think that should take care of the weeping. Also was thinking of putting a little RTV silicone around that area, so as to make a secondary seal.

I really appreciate your help guys.

 

[OGBeno]

Victor--

The birf should be repacked with Moly grease (gray, dark peanut-buttery consistency stuff)....not the M1 which is red and is for the trunion and wheel bearings...

Cool?
-o-

 

[elmariachi]

I used the exact same grease, in both knuckles. Yes it was Mobil 1, syn. Rookie, do you agree with Jim, that it might be the inner axle seal, or should I not worry about this? Appreciate your thoughts.
Thanks

I am going to have to recant my prior post, which made from home using my POS monitor. I am on my new Dell flatscreen here at work (and I am sober) and the leak does look red. I think the comments about the Mobile 1 synthetic separating may be valid, which sucks. I guess now I need to keep an eye on mine, seeings how this was the first time I used M1 red. However....

I only use the bearing grease in the upper and lower knuckle bearings, never in the birfield joint and cavity. The FSM calls for moly and I wouldn't recommend deviating from that. So if your birfield cavity is full of M1 red, you might need to tear them down and rebuild with moly.

 

[Biff]

Victor--

The birf should be repacked with Moly grease (gray, dark peanut-buttery consistency stuff)....not the M1 which is red and is for the trunion and wheel bearings...

Cool?
-o-

Got it. was thinking of using this what do you think?

 

[Curran]

Biff,
I'll tell you exactly what your problem is. (I speak from frightening first hand experience on this one.)
See THIS THREAD
I recommend fixing this ASAP!
The studs that attach the steering arm to the knuckle are loose. This is a often overlooked piece of a front axle service that can have disasterous consequences. The studs are not press fit into the housing. They screw in and should be re-torqued into the knuckle prior to putting everything else back together. [This step is left out of the FSM.] If they are not properly tightened into the housing the studs will begin to back out no matter how tight you torque the nuts.
Look carefully at the damage in my pictures. My steering linkage was essentially being held together by one loose stud. Had that las stud failed I fully believe I wouldn't be here to pass on this info.

Curran

 

[OGBeno]

Biff,
I'll tell you exactly what your problem is. (I speak from frightening first hand experience on this one.)
See THIS THREAD
I recommend fixing this ASAP!
The studs that attach the steering arm to the knuckle are loose. This is a often overlooked piece of a front axle service that can have disasterous consequences. The studs are not press fit into the housing. They screw in and should be re-torqued into the knuckle prior to putting everything else back together. [This step is left out of the FSM.] If they are not properly tightened into the housing the studs will begin to back out no matter how tight you torque the nuts.
Look carefully at the damage in my pictures. My steering linkage was essentially being held together by one loose stud. Had that las stud failed I fully believe I wouldn't be here to pass on this info.

Curran

That thread is very very good...thanks a bunch for taking it to the top...
-o-

 

[Biff]

Biff,
I'll tell you exactly what your problem is. (I speak from frightening first hand experience on this one.)
See THIS THREAD
I recommend fixing this ASAP!
The studs that attach the steering arm to the knuckle are loose. This is a often overlooked piece of a front axle service that can have disasterous consequences. The studs are not press fit into the housing. They screw in and should be re-torqued into the knuckle prior to putting everything else back together. [This step is left out of the FSM.] If they are not properly tightened into the housing the studs will begin to back out no matter how tight you torque the nuts.
Look carefully at the damage in my pictures. My steering linkage was essentially being held together by one loose stud. Had that las stud failed I fully believe I wouldn't be here to pass on this info.

Curran

Thanks for the info. Curran, makes alot of sense. I will torque all the studs to spec as soon as I open the knuckle up.

 

[flintknapper]

Got it. was thinking of using this what do you think?

If you're going to use the Valvoline (I did) then just buy the #986 full synthetic in a 1lb. tub. Also, I packed the trunnion (knuckle bearings) with the same moly grease I used for the birf.

They (the bearings) live in the same spot and need a grease capable of withstanding high pressures. The weight of the front end and all dynamic loading is directed to this spot.

Good luck.