Hino Brake Problems

blondechick · May 4, 2010

We have a 06 Hino 338. I've read all the post about "Hino Brake" problems, but I haven't seen our problem mentioned.

Our driver's side brake is making a clunking/popping noise. We have replaced the slack adjusters twice. Our mechanic says "it's not taking the grease", he has to remove it and manually pack it with grease (this helps for about 3,000 miles). My co-driver obsessively greases our truck, so it's not from lack of grease. This problems is becoming frustrating and we are afraid it's going to "clunk" while going over the scales and get us DOTed. They are in adjustment, and we don't know what else to do. Any advise would be welcomed. Thanks.

greg334 · May 4, 2010

I had the same problem, it wasn't an adjuster but the cam follower pins on the brake shoes. I lubed the follower pins with a good synthetic grease (not a lot) and it hasn't happened since.

Make sure you also check your clevis pins and use anti-seize on them. Lube the Brake Cam too.

piper1 · May 4, 2010

Sounds like a flat spotted or seized shoe roller (pin) like Greg says.

Any time something that should take grease has to be "hand packed" is a sign of two things, 1) it needs replaced or fixed, and 2) I'd be looking for a new mechanic. How exactly does one "hand pack" a slack adjuster?

It's brakes, they aren't right, fix them. I'd be more worried about my own safety than a DOT hassle.

blondechick · May 4, 2010

Greg,

I'm not mechanically savvy (I know enough to do a PTI), so I'll have my co-driver read this post. I know that he is getting all the grease zerks with hi-temp grease, but it sounds like the lubing and anti-seizing you are doing is above and beyond grease zerks.

moose · May 4, 2010

Call the Hino road side service , tell them it is not an emergency ,
they are very good in working with the dealers to solve problems .
& please let us know what it was so we can check it on our trucks .

blondechick · May 5, 2010

Piper1, Thanks for the info. We are worried about safety, but we're at a lose. We've had 3 set of different mechanics eyes on this problem. We had both driver and passenger brakes "clunking" in Oct '08. We took it to the Jacksonville, FL Rush. They replaced "slack adjusters & shims". The passenger side has not "clunked" since. It was just a couple months later that the drivers side started "clunking" again. It is intermittent, meaning it likes to stop on the way to the shop (and it's not "clunking" today). It is also not related to how hard we brake. The greasing seems to help, but it's only a cover for the real problem. One mechanic in Albany, NY said they were out of adjustment, he adjusted them, and on the way to pick up our next load...the clunking started back. We just replaced the slack adjusters again in March. My co-driver is mechanically savvy, but we haven't bought the tools (jackstands, and deep well sockets) to handle taking off the wheel so he can look at it himself. We will have those items by our next hometime. He is going to check all the rollers and look for flat spots suggested by Piper and lube everything suggested by Greg.

Moose, we are past our 3 year warranty, so last time we called Road Side Service they told us to only call if we were still under warranty, to check the Hino website to find a dealship. I will post as soon as we find out what the real problem is. I'm still open to more feedback. Something is wrong. I just don't know why 3 mechanics haven't found it, and why slack adjusters in '08 fixed the left side, but not the right??

blondechick · May 5, 2010

Also Piper... I did a poor job explaining the "packing with grease". Forgive my female brain, let me try again: The grease zerk between the s-cam and the slack adjuster has a Y in it. Grease is flowing back towards the slack aduster, but not towards the s-cam. The mechanic said the seal was not allowing enough grease to get through. So I guess he's hand packing/greasing the s-cam? Does that make more sense? Should it have to be done that way?

piper1 · May 5, 2010

blondechick said:
Also Piper... I did a poor job explaining the "packing with grease". Forgive my female brain, let me try again: The grease zerk between the s-cam and the slack adjuster has a Y in it. Grease is flowing back towards the slack aduster, but not towards the s-cam. The mechanic said the seal was not allowing enough grease to get through. So I guess he's hand packing/greasing the s-cam? Does that make more sense? Should it have to be done that way?

Ok...that's some very helpful information. First off...no, you should never have to hand pack a cam tube. If they have shimmed up the slacks it sounds like they took the easy way out, your real problem is likely worn cam bushings. If you are going to keep the truck, replace the cams, the bushings and the slacks. While you have the wheel off, check the shoe rollers for any flat spotting, and check the area on the shoe where the roller rides for any deformity or sloppiness. If any of the above is present, replace it all.

When you install the cam tube seal that is at the wheel end of the tube, install it so the seal lip points inward (toward the slack). The seal on the slack end of the tube should be installed facing the same way (out toward the slack). This will allow grease to fill the tube, but the pressure will expel outward away from the wheel (otherwise if you or some greenhorn at a Speedco gets a bit aggressive with the grease gun it would go inward and puke all over your brakes).

blondechick · May 6, 2010

Piper1,

Thanks for all the information. While it's like a foreign language to me, my co-driver understands completely. He'll get that wheel off, give it a once over, and I'll post back what he finds. It's nice to have a website to post problems like this, especially with mechanics becoming as slack as they are. From the mechanic in Albany, NY "POP? They all pop!", I think the DOT believes otherwise.

Thanks again!!!!

greg334 · May 6, 2010

I had a LOT of inspections and not once did a DOT officer say a word about it. They were concern with the play in the adjuster, the issue with the ABS wiring rubbing up against the brake hose, the issue with the clevis pin and so on but never the popping that happened.

Dakota · May 6, 2010

Mine clunks alot, even during inspections and the officer didn't say anything
I've grown used to it, and it passes every inspection/PM

EASYTRADER · Jul 8, 2010

Indently,
Hino brakes, are actually merritor brakes. Mine pop occasionally to, then again so did the brakes on my volvo tractor.

I think Greg is mostly right, its probly just a lubrication issue.

blondechick · Aug 1, 2010

Sorry it's taken me sooo long to get back with an answer...it's taken us this long to really find an answer.

The brake shoe had a hairline crack in it. The mechanic said the tension spring on the brake was pulling the shoes out of alignment and that may have caused the crack.

New shoes, new spring, a good lubing, and ahhhh wonderfully quiet brakes.

Thanks for all your suggestions.