Hi Dave and Mary
First off welcome to Sunline Club! Glad to have you with us. I could not tell by your sig what model Coach you have but it is a 2007 with a slide so that is at least in the 8,600# GVWR series camper.
As 264SRinPA Mike said, Sunline has installed both the Dexter EZ Lube and they used AlKo ultra lube axles. Don't know why they switched back and forth but they did.
Here see an Alko pic of it.
Basically there is a hole drilled down the center of the axle spindle that then is cross drilled to come up just behind the inner bearing. A double lip grease seal with spring is used intending to keep the grease away from the brakes. As you pump grease in, it comes up behind the inner bearing them out thru the outer bearing then out the end of the grease cap into a glob in your hand.
This concept is different then a bearing buddy. As the bearing buddy pumps in from the outer bearing, then thru the inner bearing and well if you keep pumping, out thru the inner seal and then up into the brake area if your trailer has brakes. Where TT's do.
This concept was originally designed for the boat industry. And it has now made it into the cargo trailer and TTís.
You can ask 6 mechanics if they are OK or not with brakes and you will get probably at least 4 different opinionsÖ
Hear see this pic.
That is off my TT when I pulled the brakes drum off a few weeks ago. That inner seal is what we nick name, blown out. It has nick or tear in it and grease comes out, gets all over the inside of the drum and then on the brake shoes. Not good.
That was on a standard axle setup. No EZ lube, No Ultra lube. I bought my recent TT used. What I suspect happened was, my TT was from PA. In PA they have mandatory vehicle inspection. I know NY does too. Here in Ohio the wheels can rot off first and then they will give you a ticket. It use to be in NY they had to pull 2 wheels and check the brakes on a car. I assume a TT may be the same too. So they did a quickie, pulled the drum, looked at the brakes and pushed the drum back on and tore the seal. Or they messed it up from day one. The end result however is, the seal had a tear and grease goes a flyin. Didn't matter std axle setup or EZ lube.
So what is my take on this on a TT?
I just bought new TT axles. I did buy the Ultra Lube feature. It was only $10 upgrade. Not a big deal.
I do my own service work and I hand pack the bearings. I packed the bearing on my Ultra Lube option axles just like I would of on a standard axle.
New double lip seals always go on every time I pull the drum regardless of greasing option. Now a days they are like $2.50 a piece for most of them you can get (off shore) unless you get the real high end industrial ones in the $10 range. And some places still charge the $10 for the same off shore seal tooÖ. It is really hard now to not get off shore type components in this type of materials.
If I ever actually grease the bearing with the Ultra lube it is a must to use a hand grease gun and pump really slow. Ideally the TT is up off the ground and the tire is slowly rotated while pumping. This is to help the grease not build pressure between the inner bearing and the seal to blow thru the seal.
Since I keep after the axles the grease does not get hard. I would not recommend using the EZ lube feature on axles that have gone many years and the grease never changed. Packed/caked grease does not flow easy and again pressure builds and can increase the chance of blow out.
To check the brakes on a TT the only way to do this is pull the brake drum. Well if you always subscribe to put a new seal in every time you pull the drum, well repacking and checking bearings is not that much more.
So how would ďIĒ use it? Well if I was going on a very long trip where higher heat could come, I have an option to add a little fresh grease pending how long it has been since I actually did a repack. For me this is about all I would use it for.
So when do you pull the brake drum, check brakes and regrease the bearings? Many axle manufactures state annually as a course of standard practice. This does fit if you use your TT a fair amount of milage every year. However if you only put 1500 to 2,000 miles on in one year, well the grease is not going to turn bad and the brakes are not going be in rough shape as they where hardly used.
If you go 6,000 to 8,000 miles well that is different and a check is a good thing, thus comes the new grease job. This is not to say that a good working TT doing 15,000 miles a year is an issue to not make it a year. If your bearing pack canít make it that long, they did something wrong.
I would not exceed 2 years even if on the 2,000 mile annual thing as rust and other things can set into in the brake components.
So, where does this leave one on a TT? If you end up going 2 years between brake drum pulls, having a EZ lube greaseable axles means you can freshen up each spring but take it easy when doing so. If you end up doing 1 year between brake pulls, well I have not figured out the gain just yet. But again I did spend the whopping $10 to upgrade my axle to have the option. If grease is applied properly and you have good seals and not caked up grease, the concept does work well.
Hope this helps and happy camping