Self adjusting brakes

JBarca wrote:

GrandpaKip wrote:
I am considering replacing my brake assemblies with new ones that have self adjusting brakes when the time comes to reshoe. They are not that much more costly than buying new shoes. Wondering what anybody else's experience has been. The axles are 3500# Lipperts with 14" hubs. For around $250, I get all new.

Hi Grandpa, (I'm one too and proud of it!)

I was one of the early ones on the forum to upgrade my camper with Dexter self adjusting brakes. They do work well and I'm still using them. That said I did have a hurdle or two to work through.

The post has my install and a lot of pics.
Dexter Self Adjusting Brakes (long W/pics and details)

The Dexter's are "forward or reverse" adjusting. Basically they work on the concept of when excess running clearance comes between the brake shoe and the drum ID, there is enough brake shoe travel that the pawl makes a click of the adjuster. That one click is not much movement, I think it was like a 7/16-20 fine thread on the adjuster so 1 click (5 to 10 deg rotation) may have been approx 0.001 to 0.002" adjustment. They want it that fine so you sneak up on the adjustment.

That said I did have 1 wheel give me a hard time and it was not the fault of the Dexter self adjuster. It was the fault of the darn brake drum run out of the original drums. Trailer wheels are not considered "precision" in any stretch of the imagination. Not that they cannot be, just it costs a fraction more time to make the same drum casting precision verse poor. With 0.028" TIR, (out of round) running of the drum surface to the wheel bearings, this issue will go unnoticed on manual adjust brakes but not self adjusters. When you adjust manually you hear a drag then nothing then a drag. The nothing is the run out (air space of out of round). Since you set them for the drag and they do not adjust, well they do not stop as good but they do not cause a major problem.

On self adjusters that much run-out can cause a problem. The shoes adjust up into that excess run out area and they get too tight. If your drums spin within 0.015", then they will work OK. Auto drums back in the day use to spin within 0.005" TIR or better and had the reverse adjust feature.

I know I may be more into the details of these things then the average RV'er, but they do work well when all the parts are right and I'll put more on when they wear out.

Good luck with yours. Lippert is now selling forward self adjusters too. I do not know if they make them or have someone else make them for them. They may or may not be the same as the Dexters. There is not a lot of parts difference between to make them self adjust.

Hope this helps and good luck

John

PS Here is the Lippert self adjuster http://www.lci1.com/self-adjusting-brakes

The Dexter http://dexteraxle.com/inc/sdetail/1497/48429
Dexter flier http://dexteraxle.com/i/u/6149609/f/product_flyers/Nev-R-Adjust_8-12.pdf

Where I bought mine. Price is good. Even better when on sale. My 12 x 2" where like $39 the entire brake ass'y back in 2009 http://www.easternmarine.com/Electric-Trailer-Brake-Assemblies/

Excellent write-up. I am very early in figuring this out. Thanks for all the info.

GrandpaKip wrote:
I am considering replacing my brake assemblies with new ones that have self adjusting brakes when the time comes to reshoe. They are not that much more costly than buying new shoes. Wondering what anybody else's experience has been. The axles are 3500# Lipperts with 14" hubs. For around $250, I get all new.

Hi Grandpa, (I'm one too and proud of it!)

I was one of the early ones on the forum to upgrade my camper with Dexter self adjusting brakes. They do work well and I'm still using them. That said I did have a hurdle or two to work through.

The post has my install and a lot of pics.
Dexter Self Adjusting Brakes (long W/pics and details)

The Dexter's are "forward or reverse" adjusting. Basically they work on the concept of when excess running clearance comes between the brake shoe and the drum ID, there is enough brake shoe travel that the pawl makes a click of the adjuster. That one click is not much movement, I think it was like a 7/16-20 fine thread on the adjuster so 1 click (5 to 10 deg rotation) may have been approx 0.001 to 0.002" adjustment. They want it that fine so you sneak up on the adjustment.

That said I did have 1 wheel give me a hard time and it was not the fault of the Dexter self adjuster. It was the fault of the darn brake drum run out of the original drums. Trailer wheels are not considered "precision" in any stretch of the imagination. Not that they cannot be, just it costs a fraction more time to make the same drum casting precision verse poor. With 0.028" TIR, (out of round) running of the drum surface to the wheel bearings, this issue will go unnoticed on manual adjust brakes but not self adjusters. When you adjust manually you hear a drag then nothing then a drag. The nothing is the run out (air space of out of round). Since you set them for the drag and they do not adjust, well they do not stop as good but they do not cause a major problem.

On self adjusters that much run-out can cause a problem. The shoes adjust up into that excess run out area and they get too tight. If your drums spin within 0.015", then they will work OK. Auto drums back in the day use to spin within 0.005" TIR or better and had the reverse adjust feature.

I know I may be more into the details of these things then the average RV'er, but they do work well when all the parts are right and I'll put more on when they wear out.

Good luck with yours. Lippert is now selling forward self adjusters too. I do not know if they make them or have someone else make them for them. They may or may not be the same as the Dexters. There is not a lot of parts difference between to make them self adjust.

Hope this helps and good luck

John

PS Here is the Lippert self adjuster http://www.lci1.com/self-adjusting-brakes

The Dexter http://dexteraxle.com/inc/sdetail/1497/48429
Dexter flier http://dexteraxle.com/i/u/6149609/f/product_flyers/Nev-R-Adjust_8-12.pdf

Where I bought mine. Price is good. Even better when on sale. My 12 x 2" where like $39 the entire brake ass'y back in 2009 http://www.easternmarine.com/Electric-Trailer-Brake-Assemblies/

RoyB wrote:
I'm pretty sure they do the same. They have the same rotating STAR gear you use the brake adjusting tool on.

I back up and put on my brakes to adjust them at any rate haha...

NOTE: was reading up on electric brakes and self adjustment. One comment was the brake controller will not work when in reverse. so the answer may be NO. My 2010 Ford built-in brake controller will kick out from 10MPH down to 0MPH. Hopwever using the manul slide activates the brakes no matter what speed you are going so I don't know about that statement they don't work in reverse.

Roy Ken

Some brake controllers like the old Voyager I had would not work in reverse. This was a major issue when I got stuck in traffic on 12% hill. I had to stand on the brakes to keep myself from slipping backwards. That's why I bought a Prodigy - it will work backwards.

I have self adjusters on ours.

Don't know if the same star adjuster, but the manual does say back up to adjust.

Has worked well for us.

I'm pretty sure they do the same. They have the same rotating STAR gear you use the brake adjusting tool on.

I back up and put on my brakes to adjust them at any rate haha...

NOTE: was reading up on electric brakes and self adjustment. One comment was the brake controller will not work when in reverse. so the answer may be NO. My 2010 Ford built-in brake controller will kick out from 10MPH down to 0MPH. Hopwever using the manul slide activates the brakes no matter what speed you are going so I don't know about that statement they don't work in reverse.

Roy Ken

Good question, I was wondering the same thing. Also, are they like auto brakes where one has to be going backwards and stop for them to adjust? (Probably)