I had my stock u joints replaced with precision u joints at the same time my clutch was done. Installer said to greae them one pump everytime I changed the oil. I have my gun all ready to go ( I have never had to use one of them before). Do I just push the grease gun fitting over the u joint zerk or does it lock on some how? THank U~

 

When guns are new they will lock on usually, and you can just pump, as the end on the gun wears in you usually have to hold it one the fitting. HTH

 

You would simply push the grease gun fitting onto the zerk, as you mentioned. Albeit, the grease gun fitting will easily move or pivot on the zerk, it is considered as locked on. You must pull back on the grease gun fitting in order to remove it,once you have pumped enough grease in.

 

Awesome thanks! Does 1 pump sound like enough? Should I be looking for it to come out some place?

 

I normally pump until I see new grease come out past the seal, and not just on u-joints but on everything. Some people will say not to push grease past the seals because it introduces foreign objects, but over the life of the u-joint the grease is going to get pushed past the seal eventually from continually adding grease to it. Also, if you grease stuff regularly than you shouldn't have problems with foreign objects in the first place.

 

I don't agree with you on greasing U joints If you push grease out of one seal that is the one that the grease will come out of after that and the other three bearings won't be properly greased. I use a small pistol grip grease gun for U joints and you can feel resistance when the joint is greased without any grease showing.
Jim O

 

Some U joints require a special fitting (narrow extention) on your grease gun, because the standard end will not reach and fit over the zerk. It just depends on where your zerk is located and how much clearence you have. The extention grease gun fitting is available at most good auto parts stores. I had to use one to grease the U joints on my Cummins powered Suburban.

 

Like I said, the grease you pump in there continually at service intervals over the life of the u-joint doesn't just magically disappear...it's going to be pushed past one of the seal eventually. Plus, just putting in a slight bit of new grease until you feel resistance isn't going to do anything for the life of the u-joint because the needles aren't getting any new grease, their just swimming in the old stuff. A u-joint is basically the same design no matter what application it's in. On my 6' ft' finish mower I pump in grease until I just get the new stream of grease coming out, and it comes evenly out all 4 cap seals. I have no doubts it would do the same on an axle u-joint.

 

I was poping the seals on my precision replacement u-joints and they failed in about 40,000 miles. Consider the environment of dust, dirt, water, etc that they run in, if you allow the seals to unseat which then later allows water spray to work in, I suggest not poping the seals if possible. Water I believe is the real enemy. Once it makes it past the seal, centrifugal force will drive it down to the needles.

Farm implements do not see the pressure water spray type of environment that your drive shaft does when traveling at highway speeds.

This set my goal is to not unseat the seals when I grease them. Good thing the precision units I have are a life time warranty.

 

No of course not, but those are all good reasons to simply go sealed. If a grease-able won't last when it's properly greased, (because no matter what you do, grease doesn't disappear and it'll come past the seal eventually from continually adding it to the u-joint), then whats the point of installing a part you to have to maintain if it won't last if it's maintained. I know others haven't had as much luck on stock u-joints, but (knock on wood), I have 56k so far on my 06 stockers and 174k on my 92' stockers, (but they need to be replaced right now). No to mentioned the sealed ones tend to be stronger than the grease-ables since they aren't hollow.

But, we all have to do what works for us, so I hope you have better luck this time.