Sorry, this is a long one. Finally got the 5th out for 2 trips after buying it late last fall. One was 600 miles round trip and the other was 240 round trip. When I started down our gravel road for the 1st trip, I tried a gain of 6, no lock-up. Then tried 8, then 10... progressively better but no lock, on gravel. At this point I'm committed and no turning back. On the way, I had the opportunity to perform my first panic stop for a deer. Truck brakes were cycling on ABS and although the trailer was not at full power, hauling it down from 60 to 20 was no problem and actually fairly impressive.
Next stop was a gas station after a long hill. Felt the brakes, only 3 were hot, 4th was ice cold. Nice feature on a brand new trailer. Looked it over a little at the campground but nothing obvious and I wasn't going to pull the wheel off. Later, at home, started adjusting the brakes and I lost count at probably 4 turns on the star on the cold brake. The others were also loose but not as bad. Figured this had to be the problem.
2nd trip started down the gravel, gain of 10, no lock, same performance. Checked the drums after a stop, same one was still cool. Made the full trip of 240 miles using the brakes several times and the one drum was still cool but not ice cold.
Pulled the drum off tonight and found a little oil/grease on the magnet surface and drum but not a lot. Cleaned with brake cleaner and reassembled. Pulled the break-away cable and it would drag when I rotated it forward but would still turn by hand. Jacked up one of the 3 that work and I could not rotate it, completely locked up. Ohmed out the entire system and got 1.1, which is acceptable, as far as I know.
So, question #1, is it possible that the brake/magnet still need to wear in more? I would think that even new parts could stop me from rotating the wheel at full power.
#2: Do you think it's the magnet, even though it ohms out ok?
Finally, my concern about performance. These axles are the 4400 lb lippert/axletek which have 3500lb spindles/10"brakes and 5200 lb tube (not happy about this). The fact that I can't even lock the 3 good tires on gravel makes me furious. The equivalent braking force is less than that of tires skidding on wet pavement. In addition, one is not working at all. Luckily, my truck is able to keep all 4 on ABS on dry pavement. So, what sort of braking potential do I have? Well, if all 4 worked, assuming the effective friction coefficient would be around 0.5 (that may be optimistic) and the truck can take full potential of the 0.8 that the harder E tires provide, Iโm at 82.1% of what I could have if the trailer could be near lock on pavement. With only 3 working, Iโm down to 74.6%. You may be thinking I should have bought a ยพ ton. Assuming a gas ยพ ton would be 500 lb heavier than my 6100 lb F150HD, it would provide less than 1% better performance, which translates to about 2โ better in a 200โ stopping distance. Thatโs not going to cut it. I need better trailer brakes. First step is to get all 4 working. Then, when I get time, these inadequate 10โ brakes are out of here. Thereโs a lot of focus on trucks but we need more on trailer brakes. How many out there take them for granted. How many adjust them to lock only on gravel and not on dry pavement? The puny brakes are fine for the guy that doesnโt want to take the time to fine-tune but I want full power.