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Topic: Slide Pin Question (Read 647 times) previous topic - next topic

Slide Pin Question

On both front brakes, the top and bottom slide pins appear to have roughly the same length from the inboard boss to the end of the pin.  If the bottom pin has 1/2" then so does the top pin.  If the other front brake has 3/8" on the bottom pin then the top is about the same.

However on the drive axle and the tag, the top slide pins seem shorter that the bottom slide pins.  I didn't actually measure them but if, say, the bottom free length is 1/2" then the top is maybe 1/4". 

Is this normal or should the drive and tag axle brakes' top and bottom pin lengths be roughly the same?

Re: Slide Pin Question

Reply #1 –
It's actually an indicator of brake wear according to the manual. As long as a set of pins haven't been replaced with a different length there is a measurement for how much should stick out when brakes are worn out.

For easy monitoring you should investigate if pins on the same wheel aren't equal (pads won't be wearing equally then) or if one wheel shows an accersltes change compared to its mate.

Re: Slide Pin Question

Reply #2 –
Quote from: its toby –
It's actually an indicator of brake wear according to the manual. As long as a set of pins haven't been replaced with a different length there is a measurement for how much should stick out when brakes are worn out.

For easy monitoring you should investigate if pins on the same wheel aren't equal (pads won't be wearing equally then) or if one wheel shows an accersltes change compared to its mate.
Hey Toby, thanks for the response. If it were one brake doing it, I'd think I have a binding caliper or similar.  But doesn't it seem strange that most if not all 4 of the rear brakes have less slide pin showing on top than bottom?  I need to get back under and look more closely.

On the other hand, when Keith Risch inspected the coach, he said the slide pins look fine.  Maybe no big deal.... just a newbie question.

Re: Slide Pin Question

Reply #3 –
Did you thumb through that manual I linked in your recent question thread about lubing the slack adjuster?  Might find the answer there...

Re: Slide Pin Question

Reply #4 –
Hey Chuck. I did then and again today.  Not seeing anything about uneven wear. 

We could make up a new acronym for, "I searched but didn't find anything" (ISBDFA), since we start so many posts with that phrase!!

So... ISBDFA specifically about this in a search of the forum either. 

Re: Slide Pin Question

Reply #5 –
Quote from: Mark Duckworth –
So... ISBDFA specifically about this in a search of the forum either.
SEE, that's just what I'm telling Glen and Amy in another concurrent thread!  Something new comes up almost every day, and we ALL have the chance to learn.  I don't know the answer to your question, and if the Meritor manual didn't cover it, then I'm not sure where to look next.

Some smart Forum member will pop up with the correct info, or a place to find it.  Then we will ALL get a little smarter!

SO, all we gotta do is wait.........................ZZZZZzzzzz  :sleepy:

Re: Slide Pin Question

Reply #6 –
Mark,just had my front wheels off the other day and cleaned the slide pins,don't remember on the back but you can take a flashlight
and look at the pad itself,if too uneven may be time to change,I know stranger things have happened but there is only one pin
that is supposed to be used.Another point that opionions may vary on is,I take some teflon slide spray and spray the pins so
far has'nt hurt.

Re: Slide Pin Question

Reply #7 –
 Maybe ,slight pad "wedge" will show up at the exposed pin length.  Most pads wear on the leading side more. This would show as more pin exposed on the leading pin. 

Re: Slide Pin Question

Reply #8 –
Maybe that's what the springs help to do,even out pad wear.

Re: Slide Pin Question

Reply #9 –
there is no perfect world so yes there will be a slight variation in pad wear.  I feel there is no replacement for actually looking at the pad itself to see if there is any rust jacking or heat cracking but nice to have something to look up at without dis assembly.  Can't tell you where it was in the manual but I did see it.

Re: Slide Pin Question

Reply #10 –
I often use a 6-8in long piece of  060 welding wire , with a 90 bend at the end. The 90 leg is only maybe 3-4MM long.  Feed the wire through a wheel opening next to the caliper/pad, up to the rotor. Pull back on the wire  allowing the little hook to catch the edge of the pad.  The play from the rotor to the pad =s the pad thickness.
 

Re: Slide Pin Question

Reply #11 –
There is a tool that works like the welding rod truck. It's got a small spring loaded hook with a rod up the centre of a sleeve. End of it is marked to read the measurements. You guys wouldn't like it - it's in millimetres. Will try to take a picture of it tomorrow.