Greasing Sealed ball joints

[buck91]

Current ball joints on my '96 have had shredded boots for many years now and somehow just the occasional spray of cyclo chain lube (lots of moly and graphite) has kept them tight and trouble free. Well, they are just starting to squeak again so I picked up some low mileage a-arms off a late model Cobra (direct fit, better BJ's and better bushings). 17k miles on them. My question is, since they are currently off the vehicle it is very easy to slide a needle past the boot lip at the top of the joint without damaging anything. There is visible grease inside the boot which I can see as the boot is semi transparent; is it worth it to add more? What are the chances the original grease is incompatible with a lithium complex like valvoline synpower? Wouldn't it just be my luck that Ford used something off the wall like bentonite grease and I ruin it by adding an incompatible grease...

 

[RoadRaceJosh]

If dirt has not entered the ball joint I would leave it alone.

 

[michaelluscher]

Leave it

 

[OneEyeJack]

I think you've already identified the risk. Maybe it's better to leave well enough alone.

I've used Red Line CV-2 grease on a failing ball joint while I was waiting for a back order to be filled. It worked fine, stopped the squeaking for about 6 weeks. Beyond that I don't know. I did not mess with the new part.

 

[BISCUT]

My F150 is 11 years old and my front end is good but it needs bushings and had some noise. My guy used a needle to put additional grease in the sealed ball joints. Made a difference, Not huge, but it is noticeable.

 

[Bgallagher]

Originally Posted By: Joshua_Skinner
If dirt has not entered the ball joint I would leave it alone.


+1

 

[Chris142]

The grease needs tobe between the ball and socket.adding it to the boot does not accomplish anything.

 

[djb]

The grease has two purposes. It forms a lubricating film, which takes a minuscule quantity. The rest is a reservoir for the working fluid. With a sealed boot, only a tiny quantity is needed.

In the days of open bearings and grease fittings, grease had more to do and the volume was important. It needed to lubricate, transport broken-down grease from the film, flush wear particles shed from the soft bearings, block water intrusion and form a barrier against external grit. All of this required a larger volume of frequently refreshed grease -- usually inserted into the middle of the bearing, flowing out.

 

[Lolvoguy]

Originally Posted By: Chris142
The grease needs tobe between the ball and socket.adding it to the boot does not accomplish anything.


bingo

 

[buck91]

Originally Posted By: djb
The grease has two purposes. It forms a lubricating film, which takes a minuscule quantity. The rest is a reservoir for the working fluid. With a sealed boot, only a tiny quantity is needed.

In the days of open bearings and grease fittings, grease had more to do and the volume was important. It needed to lubricate, transport broken-down grease from the film, flush wear particles shed from the soft bearings, block water intrusion and form a barrier against external grit. All of this required a larger volume of frequently refreshed grease -- usually inserted into the middle of the bearing, flowing out.



That paints an effective picture. Looks like I'll be leaving well enough alone

 

[TFB1]

Originally Posted By: Lolvoguy
Originally Posted By: Chris142
The grease needs tobe between the ball and socket.adding it to the boot does not accomplish anything.


bingo

Wrong answer guys, if you load the boot with grease there will be some wicking action... I've stopped "creaking" noise on several sealed tie rod and ball joints with the needle injection method...

 

[SOHCman]

+1 ^

THe new grease will seep to some extent, of perhaps the oil seperation is capable of wicking down into the ball. I have been keeping some torn boot tie rods quiet for years doing this.