re-packing greasing the bearings / axle

Charlie D. wrote:

Grit dog wrote:
If it's impossible to get grease to the inner bearings without disassembly or an easy lube ( that's where the spindle is line bored carrying grease to in between the 2 bearings, right? Help the clueless), then how can one push out the grease seal on a hub with bearing buddy's..

The spindle is not line bored it is drilled. The EZ Lube system does not inject grease between the 2 bearings. It is injected between the back of the bearing and the lip seal. This seems to be what creates the issue with blowing the seal out.

I hand pack because I do not want to take a chance of blowing out the seal and I do not want the entire cavity full of grease. Just my opinion. Op, any auto repair shop can repack your bearings. Call a couple for price. May be cheaper and quicker than a RV dealer.

Correct and to further illustrate this, here is a pic of the spindle of an E-Z lube axle and you can see the zerk fitting on the end of the spindle where you pump in the grease.



Below is a picture of the hole where the grease comes out. The grease goes into the zerk thru the center of the axle and exits that hole. It is located just inside of the grease seal that rides up on that flat portrion in the picture and the grease inters the area between the larger diameter of the inside bearing and the grease seal. This is why one has to be EXTREMELY CAREFUL and follow carefully the directions such as rotating as you pump (which takes two people since one needs to be rotating the wheel while the other pumps the grease SLOWLY) and ONLY USING a hand pump grease gun since a powered one can force the grease into that small area too fast and blow past the grease seal. This significant downside is still there even with hand pumping if the conditions are just right.



Here is another picture of that exit point with some grease coming out of the hole in the axle.



Now to the meat of the main issues with these E-Z lube axles. To analyze this at my first bearing service after I carefully cleaned all the bearings I pump grease into the zerk to just where it starts to come out of that hole. I then installed a completely dry bearing and the old grease seal into the hub and mounted the hub to the axle. To properly document a snapshot I then did TWO FULL STROKE pump on a standard hand grease gun w/o rotating the hub since I wanted to get a feeling for how much grease actually got to the bearing. This was because there had been multiple posts like yours where individuals were giving their axles one to like five pumps of grease and thinking they had actually done anything. I was appalled at the result.


Below in just how much grease you get in that area with those two full pumps I described above.



As they say a picture is worth a thousand words.:p

Now here are the real issues and why these E-Z lube axles are a great idea, with poor execution and dismal effectiveness. To even have a hope of being effective the entire void between the two bearing inside the hub cavity has to be 100% packed with grease w/o voids or air pockets. The only way I can even think to accomplish this is to some how install the hub with the inner bearing and grease seal installed leaving the outside bearing out and then somehow stuff grease into that cavity ensuring you don't have any voids or air pockets. This is critical since the how concept of these axles is to pump grease into that zerk with it coming out at that inner cavity and forcing enough grease out thru the hub and thru the outer bearing so you replace a large amount of grease in each bearing. No body says how much grease you should see come out from zerk end of the axle thru the outer bearing. Also, there is absolutely no way to tell for sure if the grease pumped in or expelled has been evenly distributed around each bearing. This requires IMO a whole lot of HOPE and some serious PRAYING.

I will readily admit I didn't document as well as I could exactly how much grease one wastes in filling that hub void around the axle between the two bearings and on some more noodling my first SWAG of close to two tubes for 4 wheels once everything is said and done is I think closer to being right that my second SWAG of 1/3 tube per wheel or 1 and 1/3 tubes for 4 wheels. There is a lot of space around that axle between the bearings that must be 100% filled with grease and in any event ALL THAT GREASE in there is WASTED since that is not used with a normal hand pack bearing service. I won't even get into how you initially fill up the cavity initially w/o leaving air pockets or voids and am still wanting to see how someone SLOWLY PUMPS in grease while SIMULATANOUSLY ROTATING the wheel so you evenly distribute the grease around the bearing and don't accidently try and force a lot of grease at a concentrated spot with the least point of resistance probably being that immediate grease seal since what you are doing is forcing the grease against that seal and HOPING is pushes grease the entire length of the hub and out the outer bearing area. SORRY anyone logically looking at what is required and what is to be accomplished that wouldn't have nightmares is IMO just not RIGHT INSIDE as the ole car commercial said.

My bottom line recommendation is to ignore the EZ Lube capability and just do a regular normal disassembly, inspect and hand pack.

One final comment is that even whether your trailer comes with the EZ-lube feature or not I would also recommend doing a bearing service very soon if never done before because the amount of grease from the factory might not only keep you up at night but cause you nightmares. Below are a series of pics I took at my first service on a new trailer documenting just how little grease the factory put in. Note the scarce amount in the grease seal in the first two pics. All these pics were as found with no removal of any of the original grease from the factory and the trailer has less than 4,000 miles total on it since new.














Larry