Alko stainless steel pistons

Having sticking alko caliper issues and thinking of going the stainless pistons. Can anyone confirm the change is worthwhile?

many thanks 

Livewire's picture

Posts: 170

Date Joined: 25/11/16

 It's a problem with all the

Tue, 2020-06-16 12:33

 It's a problem with all the alko calipers. I've rebuilt mine multiple times, and wash meticulously.  Still have dramas. The company that services my trailer told me they where going full stainless only from now on. So long story short yes they are better, but a full stainless set up would be better. ( I'll be doing that next service.) I've all so found it wasn't so much the piston getting stuck on mine it was the slides. These can get flogged out over time and dry grease can prevent the movements . Some alko calipers have grease nipples which help if you pump grease in often . The upgrade to stainless is costly but if it gives me more reliability I'm in.

Posts: 808

Date Joined: 09/10/06

 Alway found Alko calipers

Tue, 2020-06-16 18:03

 Alway found Alko calipers where a throw away item after 2 years Even after servicing they where never the same. As livewire said the slides were a issue.


hilko's picture

Posts: 52

Date Joined: 27/03/18

Look at this thread here

Tue, 2020-06-16 18:23

See here more.

I've only just done it a couple of months ago...

I'll let you know whether it was worth it. Hopefully in 10 years time.

PM me if you want further info.


Posts: 11

Date Joined: 31/07/18

Alko calipers

Tue, 2020-06-16 23:44

 Hi guys ive run alko calipers for the last 15 years and found that the galv calipers with the resin compisite pistons can be a bit problimatic as the pistons arent always completely round or parallel so when they began to not completely retract i had to spin the pistons in a jig i made to fit the drill and reduce their size by only a few thou using 500 grit wet and dry lubricted with CRC and the piston would drop unassisted into the caliper bore with no piston seal in place  and the problem was solved and in my new trailer I went to the stainless stelel alko caliper I found that one caliper was starting to do the same thing after 5 years  so I spun the piston up in the drill again and with some 500 grit wet and dry took a couple of thou off the piston and problem solved. Ive had the trailer 12 years now and had no other issues. So I found that the resin composite pistons are ok you just need to fine tune them a bit 

Posts: 96

Date Joined: 27/07/16

My 4.5 ton Tri axle was built

Wed, 2020-06-17 19:40

My 4.5 ton Tri axle was built in 1993 and the brake calipers have been refurbished twice. I overhauled the trailer 18 months ago after the trailer had sat idle for a few years and it looked like the calipers and discs where total junk. It turned out they were all still serviceable, the slide pins and bushes where perfect and only needed pistons,seals & bleeders as the pistons had corrosion from the pad side. The calipers are of an early V8 Commodore.

Posts: 605

Date Joined: 28/11/16

 Interestingly spoke to

Wed, 2020-06-17 21:36

 Interestingly spoke to Martin’s trailer parts who don’t sell stainless pistons as they don’t believe it solves the issue. However the guy did mention to die grind slightly around the lip where the piston protrudes seems to alleviate the sticking piston problem 

Posts: 808

Date Joined: 09/10/06

 One thing that should be

Thu, 2020-06-18 17:08

 One thing that should be done on any caliper is a preservice.  Adding extra grease under the piston and rubber boots will help. 

Having worked in the industry and serviced and fitted plenty of calipers the best l found for ease of servicing and getting replacement internals instead of a complete caliper where the trigg hydrolic calipers. Look the same as a mechanical caliper but with a internal piston.