Well, I was at Cummins and one of the issues I had and still have is the front brakes not fully releasing. So in researching it Meritor has a update to our brakes on the older units. It seems that they are putting an extra spring in on the caliper pins and that helps force the brakes open. So, that is on order and should be in tomorrow and done by Friday. I decided that it was taking too long and drove home. IT was 180 miles and the Jeep is not a FT. We are spoiled.....
John do you have any part numbers?
My 1996 U320 driver side front was dragging one day about 6 months ago and got very hot.
I pounded on the caliper with a hammer and it stopped dragging.
It has not happened again but I do worry about it.
The Meritor slide pin return kit# is: Kit 15018.
Here's the listing from the Meritor ADB catalog:
Dave that looks like the kit. I will know late today or tomorrow when it gets in. Also rebuilding the fronts too.
Our air disk brakes will not release and will drag on rotor if:
Wrong grease is used
Grease is not fully purged after greasing
Slide pins are not cleaned
Chassis grease should not be used on brakes
John,
For others' future reference when they are doing a search - what were the symptoms? Noise? Problems accelerating from a stop?
Michelle
Barry & Cindy.
Do you have any info on the slide pin cleaning and frequency? Can they be maintained by periodic lubrication with WD-40, silicone spray, etc.
Grease was purged and replaced with the mobile synthetic a year ago at MoT and slide pin cleaned and greased then too. The symptoms were a singing on a right turn heat gun showed that side much hotter by 50 degrees in two trips around the shop. They checked and everything is in spec but meritor said that this is an issue on the front brakes.
We have someone remove the wheels and clean slide pins every few years. Slide pins come out with a 'pull-hammer' that threads into end of slide pin, after removing center locking bolt.
Cleaning them has meant wire brushing rust, etc to get them shiny and replace pins if pitted. We never lubricated them and put them back dry. Now we lightly spray the slide pins in CorrosionX. I have never lubricated them while installed in caliper. I believe that WD-40 will attract dirt as the pins are exposed. I am not sure how much help adding the little springs do to keep brakes from dragging.
Barry, I feel your right on concerning care of the pins and the WD-40, it does gum up things and for the springs, My money is on Meritor knowing how to solve the problem with the additional springs, any thing would help to push the pads back away from the rotor, and
this is not a new subject about the recommended use of the spring kit.
As with normal things, time is the answer.
Do not use WD 40 but a dab of anti seize. The cuts are in and merit or also suggested a rebuild of the caliper too as the main spring might have failed. They pinpointed the problem and even told the tech the symptoms. Exactly mine, this must be q known issue to them.
Talked with Cummins today. They said that the caliper binding in the inside where there was some dirt that had gotten in. It was hard and they cleaned it out and it now slides and glides like it is suppose too. So, that is done. I have a new Fuel water Racor as well. Now to the start batteries but I will post a different thread on that.
The front brake is working perfectly. THey cleaned it out and re installed it. I have decided to have the rest of the 5 other calipers done. They said that they have all hard parts inside and the seals looked good on the one they took apart so they will clean out the other ones and if there is nothing broken inside them they will not need the 400 dollar rebuild kit. So I should have good as new calipers. It will take about 4 hours a caliper to do. Ouch.....
John,
Why so long? You remember when my caliper froze up. The next time I was in Nacogdoches FOT did all four of my calipers in slightly less than one day. I can't think of the tech's name, but it was the one who does the front end work.
Paul
They are doing a total rebuild on the inside not just the pins. I had the pins done in a day when they were done last time too.