How Much Grease in Steering Knuckle (1 Viewer)

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@greentruck - I've already bought everything and if it's leaking at all I should get it fixed, besides. I'd rather repair the issue than just adding diff oil and grease to the knuckle.

I won't argue with that get it done approach, except to note that the grease goes in the knuckle, but the diff oil goes in the diff;)

Keeping 'em separate is part of why you do the axle service. If they mix on their own, that's an issue, but you don't want tp help them mix if at all possible. If they are mixing, that's a reason to expedite servicing. If you're getting some noise in turns from a birf and it's just low on grease, then fill and keep running until the next scheduled service would be what I'd do. That's where the habit of topping them off during intermediate servicing is a good practice.
 
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Let's return to your birf pic. Is it leaking or operating properly?

Sounds like you don't know the service history on this truck and are somewhat unfamiliar with birfs, so here's the answer.

It depends.

If the axle was filled after being cleaned up 7,000 miles ago, then there's likely an issue with the wiper seal

If that's the situation after 200,000 miles and no one has done much except maybe added some grease to this birf from time to time, the wiper seal may be functional for now.

See what looks like bare metal in the oval, eye-like pattern on the outer birf where it swivels? If the birf is working properly, that will be evenly and lightly wetted with grease. This is normal and the consumption it indicates is why you top up the grease in between axle services. It is not a leak.

One of the few ways to really tell without records whether it's a leak or just the result of not being cleaned up over a long period is to clean it up yourself and watch the results. Another way is to compare the two birfs and if one is obviously more leaky than the other, it could be an indication of a compromised wiper seal. Even if you;'re all prepared to tear into the axle, analysis like this is often useful to understand the symptoms of the issues you'll face before you dive in.
 
I don't know the history, purchased it about three weeks ago. There's grease splattered on the outside of the driver's wheel suggesting there's been a more liquid oil around which I imagine is coming from the diff (see pic below). The previous owner stated, per his mechanic, that the grease/oil mess was no big deal or nothing to worry about, I'd like to be more confident before I go any distance off-road. Here's a pic of the passenger side diff, I'm not home so can't physically feel it to see if the backside of the knuckle is moist but from the pic it looks pretty dry. I'll try to take some pics as I dig in and report back.

wheel.JPG


pass birf.JPG
 
@DirtScaresMe - the guys who's going to be my second set of hands has the pipe and I was going to do the paper trick and a 2x4 for extra safety for the floor and axle. I don't have a brass hammer (I've got ball peen, framing, rubber mallet) but got hose clamps, hoping I can make it work for now.[/QUOTE]

You could lay one of the brass drifts across the axle and whack it with a normal hammer too.
 
I don't know the history, purchased it about three weeks ago. There's grease splattered on the outside of the driver's wheel suggesting there's been a more liquid oil around which I imagine is coming from the diff (see pic below). The previous owner stated, per his mechanic, that the grease/oil mess was no big deal or nothing to worry about, I'd like to be more confident before I go any distance off-road. Here's a pic of the passenger side diff, I'm not home so can't physically feel it to see if the backside of the knuckle is moist but from the pic it looks pretty dry. I'll try to take some pics as I dig in and report back.

Interesting. That pattern in the wheel could be just from the moly grease if they didn't use a new seal under the drive plate. They leak like that, ask me how I know.

The birf does look dry in the underside pick. Need to verify that, but probably worth pulling the wheel off and pulling the plug to see what you can see. If it really is that dry...is it making noise on sharp turns at slow speed? I'd probably shoot some moly in there just to be safe unless you plan on parking it until it's serviced if it really is dry. But if it's just the pic angle, it's really got some grease on the outer ball and you can see moly covering most of the birf inside, maybe a cleanup will tell you more and be a stress relief from knowing the PO was probably an idiot and his mechanic wasn't a whole lot smarter.
 
i looked at the driver's side a little closer a few minutes ago and it's definitely leaking a wet greasy fluid down to the backside of the wheel. I think I'm better off tearing it down to replace all the seals and such and getting it back where it needs to be.
 
Seems to have been neglected. Didn't know if it was your DD or not, but if you can afford to park it until you're ready it might be for the best to go through this one before any adventures, major or minor...
 
I tend to over think everything, so this won't be a departure from that track, but...

I wanted a way to add a measured amount of grease into the knuckle and other than doing the measurement and math on my pneumatic grease guns, I've decided to use the $2.00 method.

Measuring with a kabob skewer through the observation port is useless as it can pick up grease marks with a grease pocket trapped high in the knuckle and give you a false reading. Due to this I've just decided to give them half to 3/4 a tube to each knuckle every 5,000 miles when I change my oil and service my prop shafts.

$2.00 bags at Target

64F37432-0B28-455C-9BE2-D958553862C5_zpshd68mqk5.jpg



43D2CCEF-B149-4B5B-AD64-E0B4A7D02FAA_zpsxahsxvpj.jpg


C6AC572D-BEA8-423B-AE1A-C451DD69E199_zpsayq0vwvy.jpg


Just fold the bag down over itself which makes loading the grease easier. Snip off an inch at the bottom and you are good to go.. Took about 30 seconds to get 1/2 - 3/4 tube in the knuckle without any mess.

Hope this might help someone.

Cheers,

J~
 
I tend to over think everything, so this won't be a departure from that track, but...

I wanted a way to add a measured amount of grease into the knuckle and other than doing the measurement and math on my pneumatic grease guns, I've decided to use the $2.00 method.

Measuring with a kabob skewer through the observation port is useless as it can pick up grease marks with a grease pocket trapped high in the knuckle and give you a false reading. Due to this I've just decided to give them half to 3/4 a tube to each knuckle every 5,000 miles when I change my oil and service my prop shafts.

$2.00 bags at Target

64F37432-0B28-455C-9BE2-D958553862C5_zpshd68mqk5.jpg



43D2CCEF-B149-4B5B-AD64-E0B4A7D02FAA_zpsxahsxvpj.jpg


C6AC572D-BEA8-423B-AE1A-C451DD69E199_zpsayq0vwvy.jpg


Just fold the bag down over itself which makes loading the grease easier. Snip off an inch at the bottom and you are good to go.. Took about 30 seconds to get 1/2 - 3/4 tube in the knuckle without any mess.

Hope this might help someone.

Cheers,

J~

If you have any left over you can “volunteer “ to decorate your mother in laws birthday cake!:flipoff2:
 
For a complete amateur, can someone point me to the fill plug and the type of grease and grease gun to use? I understand the concept and technique and want to give my bifields some grease...just not sure of the details
 
1) Taking the usual safety precautions, raise the truck's front axle, remove the wheel and tire. If you're looking at the end of the axle straight on, the plug will be at about the 11am position on the left side, at about the 1am position on the passenger side and jsut inside the dust shield of the disc brake. It is a plug with a square head, rather like some plumbing.

2) The spec is for a NLGI GC-LB moly fortified grease. I've been using Valvoline DuraBlend Synthetic Blend Grease, which is cheap and widely available.

3) A grease gun with the rubber hose flex line on the tip works best for me. The tip is just smaller than the opening provided when the plug is unscrewed. Stick it in there and pump until you've got what you need.
 
1) Taking the usual safety precautions, raise the truck's front axle, remove the wheel and tire. If you're looking at the end of the axle straight on, the plug will be at about the 11am position on the left side, at about the 1am position on the passenger side and jsut inside the dust shield of the disc brake. It is a plug with a square head, rather like some plumbing.

2) The spec is for a NLGI GC-LB moly fortified grease. I've been using Valvoline DuraBlend Synthetic Blend Grease, which is cheap and widely available.

3) A grease gun with the rubber hose flex line on the tip works best for me. The tip is just smaller than the opening provided when the plug is unscrewed. Stick it in there and pump until you've got what you need.
Thanks! This is within my meager capabilities.
 
We add moly to knuckles several times a year. Clean away loose dirt around square 12 mm plug before removing it. We leave wheels on rig, don't need to jack it up if you have a creeper to lay on. I add about 1/2 tube on each side 3 or 4 times a year. I do about 20,000 miles a year with quite a lot of trail time. Your results/needs may vary. You can often look at the outside of the knuckle balls and see a trace of grease from the felt wipers which can give you a general idea of how full or empty the knuckles are.
 
Yep, can be done with the wheel on. Good tip on getting the plug cleaned up before removing, too. Just that if you've never done it before, much easier to see what you're up to with the wheel outta the way.

The other issue is that if this is catching up with neglect, it's good to shine the light in the hole and evaluate. You may have to push the moly away from the inside opening of the hole to see down inside, but it's reassuring to see that the birf is still covered in lube to some degree. If not, then that's good to know, too, as it may affect future work plans.

Of course if you're conscientious about keeping up with maintenance, then you know what's going on by outside appearances and just reaching up and pumping in a top-off quantity is not a problem and does save time over pulling the wheel if that isn't needed for some other reason.
 
A zip tie works as a quick “dip stick” to check your grease level too! Just stick it down the hole until it hits bottom, pull it out ...... pow! :flipoff2:
 
1) Taking the usual safety precautions, raise the truck's front axle, remove the wheel and tire. If you're looking at the end of the axle straight on, the plug will be at about the 11am position on the left side, at about the 1am position on the passenger side and jsut inside the dust shield of the disc brake. It is a plug with a square head, rather like some plumbing.

2) The spec is for a NLGI GC-LB moly fortified grease. I've been using Valvoline DuraBlend Synthetic Blend Grease, which is cheap and widely available.

3) A grease gun with the rubber hose flex line on the tip works best for me. The tip is just smaller than the opening provided when the plug is unscrewed. Stick it in there and pump until you've got what you need.
Is the full synthetic like the one below acceptable? You mentioned that the blend is what you use. Not sure if there's any reason to avoid it.

https://www.amazon.com/dp/B000CQ4DK0/ref=cm_sw_r_cp_apa_CfGlAbJW503VJ
 
Is the full synthetic like the one below acceptable? You mentioned that the blend is what you use. Not sure if there's any reason to avoid it.

https://www.amazon.com/dp/B000CQ4DK0/ref=cm_sw_r_cp_apa_CfGlAbJW503VJ

Should be fine to use that, as it looks to be rated the same as the conventional Valvoline I use in terms of its ratings.

CAVEAT: Mixing full synth and more conventional lubes can cause issues. Hard to say if it will or not in this case. If you're just topping off and don't know what's in there, I would use the conventional stuff, because most likely that's what's in there. If you've got things apart and cleaned up for an axle service, then a full refill will not present problems with mixing the two, so synth should be good to go there.
 
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