Disc Brake Replacement: 2016 Ranger Z519 Tandem Axle

[Boatguy001]

I am looking for input on changing my trailer disc brakes; specifically, removing the caliper (and any other tips to complete the job).

I called my local Ranger dealer requesting a quote to change out the disc brakes on my 2016 Ranger z519 tandem axle trailer. The shop is set to permanently close and they advised doing it myself "as it is not that hard". I called Ranger and got the brake pad specs (1997-2000 Kia Sephia front pads) and purchased 2 sets of ceramic pads.

I watched a couple YouTube videos on changing trailer disc brakes (boats were not Ranger Boats): both videos showed the caliper bolts being fully removed with a 9/16" wrench. Once the caliper bolts were removed the caliper was free to be removed from the rotor.

I attempted to complete the job but was unable to remove the Caliper bolts. I figured out that the caliper bolt requires a 7MM Allen Key (not a 9/16" wrench as advised in the YouTube videos). No matter how many revolutions I put on the caliper bolts with the Allen Key, they are not coming out. Anyone have experience here and can provide input on how to remove (if they even are removable)?

Also, I've seen some information about compressing the caliper with an old break pad and a C clamp before putting on the pads... and opening up the brake fluid cap... is this necessary?

[mactlman]

posted same reply twice so erased this one

[mactlman]

"Also, I've seen some information about compressing the caliper with an old break pad and a C clamp before putting on the pads... and opening up the brake fluid cap... is this necessary?"

the caliper slides screws need to unthread more than come out. they float in the hole and the caliper slides freely in and out on them. if the screws are backed out of the knuckle, the calipers should pivot or lift off of the knuckle.
try using a prybar or big flat head screwdriver to get the piston to move in some, even a little, which will allow the caliper to move more.
new pads will not fit unless piston is returned to in position. have any buddies who work on cars? or a trailer shop close. really easy job usually. post in the georgia forums and see if someone on here close could help you?

[Boatguy001]

duplicate somehow?

This is my first time posting here. I did search through the forum to find an answer but the information wasn't clear. So, I posted my questions.

[Boatguy001]

"Also, I've seen some information about compressing the caliper with an old break pad and a C clamp before putting on the pads... and opening up the brake fluid cap... is this necessary?"

the caliper slides screws need to unthread more than come out. they float in the hole and the caliper slides freely in and out on them. if the screws are backed out of the knuckle, the calipers should pivot or lift off of the knuckle.
try using a prybar or big flat head screwdriver to get the piston to move in some, even a little, which will allow the caliper to move more.
new pads will not fit unless piston is returned to in position. have any buddies who work on cars? or a trailer shop close. really easy job usually. post in the georgia forums and see if someone on here close could help you?

I called a few trailer shops and they stated they do not work on boats.

The screws were backed out to the end of the knuckle, the caliper was loosened but still couldn't remove it. Is compressing the piston the step I missed? When I compress the piston, do I need to open the brake fluid cap first? Is this a job you've completed before on a Ranger?

[mactlman]

brake fill cap fine on or off--i have done brakes on basscats and stratos and most trailers are basically the same systems. I was a master auto tech in my previous field so it is all the same basic brakes systems to me.

are the pads worn out or falling apart?
do you have any buddies that work on cars? neighbor? should be a basic brake set-up.

[mactlman]

seen this video? look like your system?

[Blair B]

It’s a simple job, unless you have the calipers with a parking brake. Take the 7mm Allen wrench and remove the slider pins, they are going to be tight, you might have to put a small cheater bar over your Allen wrench. Slide off the caliper, pull the old pads out, take a C clamp and push the piston back into the caliper body. Make sure to clean and lubricate the slider pins.

[rangered]

I blew out a hub so I opted to get the whole spindle, arm and calipers all together? It was a little
more $$ but gave me peace of mind that all the hubs and stuff was new. Brakes4Trailers is a
good source for parts. Good luck

[Boatguy001]

seen this video? look like your system?

haven’t seen this video until you sent the link. It looks like the same system or very similar. I’m planning to give it another go this weekend and I’ll let you know how it goes. Thanks for the info!

[Boatguy001]

It’s a simple job, unless you have the calipers with a parking brake. Take the 7mm Allen wrench and remove the slider pins, they are going to be tight, you might have to put a small cheater bar over your Allen wrench. Slide off the caliper, pull the old pads out, take a C clamp and push the piston back into the caliper body. Make sure to clean and lubricate the slider pins.

Thanks for the information; I’ll post an update on my progress after this weekend.

[Boatguy001]

I blew out a hub so I opted to get the whole spindle, arm and calipers all together? It was a little
more $$ but gave me peace of mind that all the hubs and stuff was new. Brakes4Trailers is a
good source for parts. Good luck

Not sure I’ll go this route but good to know the option is there! Thanks for the info.

[Grits and gravy]

A new caliper is less than $200 with everything ready to install. I had one lock up on me and replaced it. Took about 15 minutes and works perfect now.

[Boatguy001]

A new caliper is less than $200 with everything ready to install. I had one lock up on me and replaced it. Took about 15 minutes and works perfect now.

Good to know that’s an option. Thanks for the info.

[Boatguy001]

haven’t seen this video until you sent the link. It looks like the same system or very similar. I’m planning to give it another go this weekend and I’ll let you know how it goes. Thanks for the info!

Video is very helpful. I was able to remove the caliper bolts only to discover the replacement pads I ordered (based on information from Ranger) don’t fit. Also, ranger mentioned they don’t use hex on the caliper bolts… wondering if the system on my boat was upgraded. Anyway, I ordered some UFP DB-35 pads and will install them! How often do you recommend changing trailer disc brakes?

[mactlman]

Video is very helpful. I was able to remove the caliper bolts only to discover the replacement pads I ordered (based on information from Ranger) don’t fit. Also, ranger mentioned they don’t use hex on the caliper bolts… wondering if the system on my boat was upgraded. Anyway, I ordered some UFP DB-35 pads and will install them! How often do you recommend changing trailer disc brakes?

my stratos was 20 yrs old when I sold it and she still had original pads. (stored in a climate controlled garage also)

[Boatguy001]

my stratos was 20 yrs old when I sold it and she still had original pads. (stored in a climate controlled garage also)

I completed the job today. I discovered one of the pads came free from its backing; so I’m glad I did the job. Otherwise, for the pads that were intact, there was still a lot of pad left.

The front, port side axel only has one line/hose going into the caliper. I looked at the starboard side to see how the hoses run and there is no line/hose coming from the front of the trailer on the port side (like there is on the starboard side); is this normal?

[mactlman]

usually the calipers are "daisy chained" together in a series.. in first one and out of the first one on one side, then to the next in line, then on to the other side of trailer and in one first caliper then out of and first caliper to second on that side.

try backing up slowly without the trailer wiring hooked up, if it stops the truck or tries hard, all is good!!! make sure master is full also!

[Boatguy001]

usually the calipers are "daisy chained" together in a series.. in first one and out of the first one on one side, then to the next in line, then on to the other side of trailer and in one first caliper then out of and first caliper to second on that side.

try backing up slowly without the trailer wiring hooked up, if it stops the truck or tries hard, all is good!!! make sure master is full also!

Braking performance is improved. You’ve been a huge help! Regarding topping off the master, my trailer documentation states that either Dot 3 or Dot 4 can be used. How do I know which type of brake fluid is currently in the system? (I understand you don’t mix Dot 3 and Dot 4)

[mactlman]

3 and 4 mix. 5 does not mix. Some bottles will say dot three and four both on the same bottle also