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Front Axle Joint Grease

10K views 9 replies 5 participants last post by  AlanMcR 
#1 ·
I noticed that the right hand "ball" was collecting a fair amount of grease on it, so I removed the plug checked the level and it's pretty low. What is an appropriate grease to top it up with? I was think Redline synthetic, but since it goes in easy and comes out hard, so I want to be sure I'm using the correct grease.

BTW, I noted that the grease that is in there is black instead of the theoretical waxy yellow. I'm not if that is indicative of a CV joint boot issue or if the previous fill was just done with black grease (or Redline that turned black). Would you suspect CV boots at 80K miles?

And while we're on the subject of CV boot, why is it that one is even necessary? It seems to me that the CV joint and the bearings could all just roll around in the same grease.

Thanks in advance,

- FD
 
#2 ·
The CV boot is needed because the CV spins and will throw the grease away from it. If the axle ball is leaking black runny stuff I'd take it apart. The worst thing that will happen that way is some early maintenance. The alternative is a potentially expensive failure.
 
#3 ·
I used Mobil 1 Grease in mine too and it was red, but it was on the MB sheet and is able to be used. I don't know how much to put in there but I put about 20 hand pumps from my grease gun. Seemed about right as it is a large cavity. The color does not matter at all (I was curious also).
 
#4 · (Edited)
The plot coagulates . . .

Thank you for the replies. It looks like things are getting uglier. The left axle ball was filled with nice looking MB green grease, but the right, while nearly empty, contained black/graphite colored grease - the color of the moly grease specified for CV joints. It seems to me that MB was rather clever to use two different colors of grease so that failure of the boot could be noticed.

So, I think the boot is blown and the lack of lubrication has caused damage to the CV joint which in turn is the cause of the vibration issue I have been trying to sort out. I feel my wallet shrinking.
 
#5 ·
Open up the fill plug on the joint housing, raise the front axle, insert a slim finger into the hole and slowly rotate the wheel. You should be able to reach the CV boot with your finger and feel for any tears/rips.

To check the wear on your CV joint, do a full turn to the right, drive slowly and listen for any clicking noise from the front CV joint. If it clicks, it's toast.
 
#7 ·
MiN - Thank you again for sharing your wisdom. I opened up the plug as you suggested and "felt" with my finger and, in addition, I used some rags poked through the hole to "clean" the grease off of the boot. Despite the presence of black grease, I could not find a rip, tear, or hole in the boot visually or by "feel" with my finger. Furthermore, I could find not discernible play in the wheel bearings or anything else on the front end for that matter.

A friend and I put the truck up on the lift (two post), locked the differentials and let it idle in gear with the tires on. It was wicked cool to watch all four wheels just rolling along in mid-air like that, but more importantly, absolutely everything was running as true as I have seen any drive train run. Not a wobble or deviation anywhere! The drive train ran like a Swiss watch. We took the tires off and ran the "speed" up and it still ran like a Swiss watch.

We also turned the wheels from lock to lock while it was running on the lift, and no clicking or other noises. We took the truck out and drove right and left circles, and still no noises or clicking.

But on the road, it still rumbles/resonates as 58 - 62 MPH. I am stumped.

Thanks,

- FD
 
#9 ·
I have had the tire balance checked and it is fine. This is not a feel in the wheel type of vibration - it's more like someone has attached a giant low frequency buzzer under the truck in that you can hear it more than feel it.

Since there is no bearing play, I don't see the need to replace all of the bearings in the right front at this point. So, my current plan is to remove the right front swivel housing while leaving the bearings and hub in place (I have read on the net that this is possible, especially on the right side with the short axle shaft). I plan to clean off all of the black grease, inspect the CV boot and replace if required (I have also read that this can be done with the axle assembly in place). I will also replace the axle to axle housing seal (009 997 28 47) since the black grease may be from differential oil leaking into the swivel housing and I will replace the axle bushing (460 337 00 49) since it's cheap and a worn bushing could be allowing the axle to vibrate. The new grease will allow me to properly assess the condition of the CV boot in the future.

Does this sound reasonable?

Beyond that, if the vibration is still present, I think I will just drive the truck and wait for something to break.

- FD
 
#10 ·
The boot can be replaced in place. It isn't a lot of fun. Heck, just cleaning out all the axle ball grease is a messy job. Be careful with the ABS sensor. If possible, gently remove it from the axle (grease it when replacing). If it won't come out, disconnect the sensor and

That being said, if you are doing the work to take apart the axle ball, I'd definitely put on a new boot. Frankly, If there is any looseness at all in the system, I'd be tempted to do the bearings and all.
 
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