I noticed my '12 F250 has grease zerks on the front axle u-joints and was wondering how often you need to grease them ? My truck has 10k on it and while I was changing the oil tonight I decided to give them a few shots of grease until it started coming out of the joint.

 

More if you don't use them or they get into deep water.

 

I believe the secret to greasing any Ujoint is to put enough grease in to lube it BUT not so much as to push the seals apart.......I know crazy ain't it? but if you can walk that fine line the joint will last for a very long time but if you push the seals out.......not nearly as long. A couple of pumps on a hand GG should do the trick, centrifugal force will distribute it to the caps. JMHO

 

I have heard this argument many times and understand the logic behind it....BUT.....my experience tells me different.

IMO you should grease a u joint until you see fresh clean grease around all 4 caps. If 1 cap is not getting grease with the grease gun it wil not get grease with centrifugal force. I have never had a greesable ujoint fail from lack of lubrication useing this method. I put a lot of miles on my vehicles. I currently have 400K+ on my SD. I was a maintenance mechanic in a former career for an OTR trucking company and policy was grease every ujoint every weekend. If a ujoint didnt get grease out of all 4 caps keep pumping until it did, If that was a fail replace it. The very few I had to replace following this policy would have failed (determined by post mortum) in short order if they had been allowed out the door and the failure would not have been detected if we only put a few pumps in every joint.

 

Agreed.......

 

I grease every other oil change or more if in water/mud.

 

That's the method I followed, 295,000 miles on the original joints.

 

thanks guys, the manual really didn't mention anything about the u joints so I wasn't sure. I'm also a believer in greasing until it comes out around the seals, it makes a mess if you don't wipe off the excess but at least you know everything got grease. I drive truck and have greased the u joints on it this way for the past 13yrs and have never had a joint failure that wasn't caused by someone getting too aggressive if they had to remove one to get the drive shaft off.

 

Well now, It would appear like I'm out number on this one. I too have been 'around the barn' on this and if you put in enough grease so it will seek its way out to the caps without pushing the seal out it will make for a tighter joint concerning mud/dirt and water than if you push the seal out with grease. That being said it would also stand to reason that more of the grease you DO put in the cross will STAY in the cross better if the seals remain intact, if the joint is not faulty when manufactured or damaged when installed there is NO reason why the grease you put in the cross will NOT be evenly distributed to all four end caps, JMHO. And for what its worth I might also add that I have owned three Semi tractors, a Twin screw Dump and two single axle dumps and various other equipment and have never replaced a Ujoint or a tie rod end (they have seals also) due to lack of grease. I guess it comes down to personal preference in this case. lol! Have a great day and an even greater Thanksgiving to all of you out there in FTE land. Mcrafty1

PS. and don't be mean, after all it IS the holiday season!

 

Agreed again, fill them with grease,
and happy Thanksgiving

 

Right back at ya!

 

This friendly debate is a lot older than the internet. I can remember my Great Grandfather, Grandfather and Father having this debate around the "forum" (wood stove) in my grandfathers truck barn.

Happy Thanksgiving everyone!!

 

Ya this argument can and probably will go on for ever. On one hand I agree with pushing the grease out past the seals as this provides fresh grease and pushes out the old contaminated stuff. But I also agree that this unseats the seal providing a path for water & dirt IF the seal doesn't re-seat its self once the joint spins and distributes it evenly. Once you unseat the seal you need to be on top of the greasing thing like every 3-5K...IF it doesn't re-seat. If you grease just to the point of not unseating the seal I believe you are better off in most daily driver cases. For something that spends all day in the mud/water grease the hell out of it...just be sure to re-seat the seals. Secondly I think what we have here is one guy has a delicate touch with some finesse on the grease gun, manual or pneumatic. The other guy has the hammer approach with a shop drum greaser turned up to 150psi. If you shoot for something in the middle I believe its the best. If you blast the grease in at 150psi you can damage the seal then failure is eminent. This is not my first rodeo either. I've worked around this stuff for 35+ years. I have found that if you grease just to the point where you see the seals(all 4) swell and see just a touch of grease weep out your at the right spot. I then rotate the joint to work the grease in. Then visually inspect the seal. I re-seat then if they need to be. This is the key no matter which method you prefer. Just be sure the seal re-seats. If not do it manually by gently squeezing the circumference of the seal to push out excessive grease then re-seat it in its groove. Some fresh grease in the groove circumference is good as it helps provide a good seal. Problem solved for both schools of thought.
The reason Ford doesn't mention the u joints is because the ops manual is written by the same people who print phone books. EX: Want to find lug nut torque? Heavens dont look under torque, lug nut or anything obvious look under wheel or tire or muffler bearings!LOL. Ops manuals are just a CYA for the maker and can be totally useless in some cases. Get a real service manual for your rig if you're gonna hang on to it.