First 5th Wheel--Bad Braking???

I would say that the trailer brakes need adjustment!!
Can you lock then up when going slow if you do it with the slide lever.
If you pull hard from stop will the brakes hold??

I had this same problem with my second 5th wheel a few years ago. We purchased it slightly used from a dealer. The brakes did not feel like they did much. I was pulling with a Ram 2500 Cummins with no exhaust brake so I noticed quickly that this 5th wheel was either significantly heavier than 5th wheel number one or there was something wrong with the brakes. I replaced my controller and saw no change. I ran a heavier wire from the controller to the connector in the bed of the truck and saw no change. The dealer claimed he had checked the brakes before I picked it up and there was no problem. He also said the previous owner did not tow much and it was just short distances to the lake where he camped. So what was the problem?

I pulled the brake drum to inspect for myself and found the brake shoes covered in grease!! The previous owner apparently used the "easy lube" grease fitting on the axle and had pumped huge amounts of grease before each trip. The grease seal could not hold it and so the brakes were covered. I was out of the 30 day warranty provided by the dealer so I tackled the job myself. I removed the brake shoes, soaked and cleaned them in gasoline and lacquer thinner to remove all the grease....or so I thought. I did this on all four wheels. After reinstalling and adjusting the brakes they were great!!! Then after a few trips I started to notice the brakes seemed less effective again. So again I pulled a wheel and could tell there was an oily residue on the shoes. My new grease seals were fine. Apparently the residue was coming out of the brake shoe. I cleaned all of them again. This helped again. Then several months later same issue!!

So the bottom line is this. Always hand pack bearing and do not use the easy lube feature. If you have grease on your brake shoes then REPLACE THEM WITH NEW ONES. You cannot get all the grease out of a contaminated brake shoe. After replacing my shoes i was able to lock up all four wheels by using the manual lever on the controller.

What year Ram do you have?? Newer ones you have to chose between electric hydraulic, electric, heavy, and light. You may need to go from light electric to heavy elecric. Also, make sure it is not set to electric hydraulic.

The newer rams have brake control options for different types of trailer brakes. Located in the Uconnect apps

bowler1 wrote:
... maybe the trailer brakes will get better as I break them in (user manual said it takes about 1000 miles to do this)...

^ This could be your problem.

When I purchased our new 5th Wheel, hooked it up on the dealer lot, pulled forward and tested the trailer brakes they did absolutely nothing. I refused to take delivery until the brakes were repaired.

After several days of back and forth with the dealer they managed to convince me the brakes weren't defective, they just needed to be broken in. They pulled a drum and found nothing wrong. According to them, the guy transporting the trailer from the factory had a faulty brake controller and the trailer brakes had never been used. They insisted the brakes would gradually improve over the first several hundred miles of use.

Turns out they were correct. By the time I got home with the trailer (50 miles) I could tell the brakes were getting better. After a few hundred miles of use they work great.

The new shoes on new drums don’t always have the same arc, so the shoes need to be be bedded in to the drums. Find a quiet backroad and do 10 stops from 30 mph using only the manual brake control.
Pull over and back up and use manual control to stop and pull ahead and manual control stop. Repeat several times to work the self adjuster feature on the brakes. You should notice an immediate improvement, or as other poster mentioned they are covered in grease.
This is how I break in a new set of brakes, hope it helps.

My brakes don't have self-adjusters. Manual adjustment only.

I just went through the same thing with my 2014 3500. It seems more common on 2015 2016 but also 13 and 14.i was telling myself exactly what you said then I pulled a new 7x14 utility trailer and knew there was something very wrong

There are self-adjusting trailer brakes on the market but our trailer builders refuse to use them.

I had my trailer back at the dealer twice due to braking being jerky at times and sometime barely braking. Both times they said nothing wrong with the camper so it must be in my truck controller. Bringing it home a few months ago and slowly coming down my street, I activated my controller and watched front drivers side lock. Nothing from other three. So that week I jacked it up and pulled the hub, everything looked good. Pulled the rear hub and found the wiring on the magnet chewed up and shorting out. Checked the other side and was good so I replaced the one magnet and all is good. Sent a picture to the cell phone to both the service manager and owner of the dealership, still no acknowledgement.