Soft brake pedal on the Dmax

It’s not a great feeling when you put your foot on the brake, and very little happens. We’d not long got back from the top of Cape York, and I thought that the brakes felt a bit weird when we rolled into Mareeba.

Sure enough, the next day with the camper off I got to do some testing, and the braking was shocking on our Isuzu Dmax, and even worse than that, I had to double pump the brake to get it to become firm, which is never a good sign.

We’ve had a fair number of issues with our Isuzu Dmax, but nothing like this before.

Recent shoe replacement

I had the rear brake shoes replaced in Cairns just under 6000km ago, and asides from getting stuck in a sandy creek I was a bit surprised at the dramatic performance change.

After some testing, I touched the front rotors which were cooking hot, and the rear drums were icey cold, which confirmed my suspicions; we had no working rear brakes.

Stuck in a creek in Cape York
We got stuck in a soft creek at Cape York, which wouldn’t have helped

Adjuster problems

Rather than muck around myself, I decided to find a mechanic to have a look, and he put it on the hoist, and tightened the shoes up using the adjuster.

However, he commented that the adjuster would spin both directions, and it shouldn’t do that; there’s a tab which should lock it and stop it reversing unless you push it in.

He pulled a wheel off, and you could see that this tab wasn’t engaging on the adjuster teeth properly, and he was suggesting that it probably came loose on its own, explaining the lack of brakes.

He then mentioned that he had an aftermarket set of brakes on a different Dmax do the same thing, and the pin that holds the tab in place seemed to be manufactured too low.

Dmax rear brake shoes
The Dmax rear brake adjuster wasn’t being locked one way
Dmax drum shoes
The mechanic suggested the tab should sit up higher on the adjuster

I hadn’t used genuine Isuzu brake pads on this instance as the mechanic who did the job wouldn’t warrant them (as he wouldn’t have been supplying them), and maybe this was a mistake.

The brakes are back, for now

Regardless, the brakes were re-adjusted tight, and we got our handbrake back (which had also completely died, for the first time), and the brakes were working perfectly fine.

In the past, we’d get a tight handbrake after going through mud or water, and it would gradually wear and need a higher pull on the lever, but it had never completely failed, and in this instance it was so bad that I couldn’t even get it to hold on a mild hill, on full height of the handbrake lever.

I didn’t think that the shoe adjustment would make the pedal sink to the floor and be soft, but it clearly does. We’ve now got working brakes, I can easily adjust them if needed (just hop under with a screwdriver), and I’ll be following up with the first mechanic about the brand of aftermarket shoes, and whether they’ve been manufactured incorrectly if they start to fade again.

This is the first time I’ve really looked into drum brakes on anything other than a camper trailer, and it was an interesting learning experience. 

Digging into the issue

After writing this post, I had quite a few people comment or get in touch saying they’d had similar issues, and decided to keep digging.

Our brakes are still working OK, but I’m not sure if they’ve deteriorated at all. I contacted the original mechanic, who was very supportive, and told me the brake pads fitted are IBS, and part number NS3093. 

I believe these are distributed by the same parent company as the Protex brand, and I’m waiting for information back. So far, there’s a couple of different options:

  • The wrong brake shoes were put in the right box
  • The wrong brake shoes were installed (mechanic got the wrong ones), which seems unlikely given my discussion with him
  • The shoes were not manufactured correctly.

My gut tells me the bottom option is likely (given the information I’ve obtained so far), but I don’t really know. For now, I’ll wait to hear back, and monitor my brakes carefully. It’s a pain in the backside though.

Do you run genuine parts? Have you had any issues with your Dmax rear brakes?

Sharing is caring!

Similar Posts

Leave a Reply

Your email address will not be published. Required fields are marked *


  1. Hey Charlie,

    That’s a pain. You might have to revert back to OEM gear. I’d have just replaced like for like if I had my time again

    All the best!!

  2. Just back from the mechanic who couldn’t Bendex shoes fit into my Dmax drums, I know the dealer swapped some part of the adjuster last service so possibly there is some confusion which adjuster fits these brakes.

  3. Hey Cleve,

    Cheers for sharing. I wonder how many people are having issues.

    Hopefully yours is all good

    Take care

  4. I’ve just checked with mechanic they’ve installed protex N3342 so I hope they’ve reinstalled the correct adjuster on each side and the adjuster is correct size.
    I’ll keep you informed.

  5. Great read, I’ve just had my rear brake shoes installed and presented a bit spongy but it’s too early to tell if I’ve got the same problem, mechanic said they are non genuine and they need to bed in. Time will tell, but I’ll certainly be watching for fade or no brakes.

  6. Hey Peter,

    That is very interesting. Mine were IBS brand, sold through Bursons. There is a slim chance the wrong ones were fitted, but given you and I aren’t the only one to experience this it wouldn’t surprise me if the pads aren’t correct.

    I’ll update this when I have more information

    All the best

  7. Hey Brett,

    Fair comments. This was a direct replacement of the OEM part, but there were two different options.

    I’m in discussions with the shoe manufacturer now

    All the best

  8. Hey Terry,

    I’ve had a few people tell me that now too. Is this with aftermarket parts, or the genuine Isuzu ones? I never had an issue until I swapped

    All the best

  9. Hey Joe,

    Interesting. I hadn’t heard of that before.

    Thanks, and all the best

  10. You are right on the money with the adjuster pivot pin being in the wrong place.. I have found that exact problem.. protex brand I believe. got a set of DBA shoes and problem solved.

  11. I’m a diesel mechanic have worked on trucks cranes and cars you need on new cars cermic rear pads or they wear quicky make noise due too excess dust also should replace hardware springs clips adjusters if done hard yards

  12. This is a common problem with the D MAX. My D MAX ute had zero rear brakes, found when it was serviced by a dealer.

  13. You get left and right threaded self adjusters on your rear drum brake, while driving and on brake application your brakes adjust itself, if you fit them on the wrong wheel it can cause the brake to adjust down instead of up.

  14. Hey Christopher,

    Unreal mate. They could even be the same parts. I’m going to give the mechanic a call and see what brand he used. I wonder if they’ve been incorrectly built. Pretty sketchy, when you think about how many people are possibly in the same boat

    All the best

  15. Christopher Steensen says:

    Hi,I’ve got a 2017 colorado 4×4 it has done the exact same thing, I had the front and rear brake pads an shoes replaced, 4500km later soft pedal no hand brake, I bleed them adjusted them good for 3 days then back to soft pedal, found out self adjusting tab wasn’t working same result genuine pads put in all good now,but the scary thing is how quick it left me with no warning!!! Thanks I thought it was just me.Chris

  16. Hey Graham,

    There’s certainly some advantages of disc brakes, and I like the idea of the conversion, but not the price. If you are towing something heavy though, its probably money well spent.

    On the flip side though, I think its just the fact that we didn’t go with OEM brake shoes, but time will tell!

    All the best

  17. Your experience has confirmed my decision to replace the standard rear drums on the DMax with discs. The improvement from day 1 was phenomenal. Was costly but worth especially as we tow a largish van.
    cheers and travel safe.