Meritor Maintenance Manual M4 and Dually Axle Seal/Brakes

[Al Anderson]

Hello All,

I have a leaking axle seal at the wheel on the dually axle and am looking for the manual to hopefully get information about replacing it.  I am also looking for a parts source for both the seal and the pads?

On a related note, the past owner/service shop doesn't doesn't appear to have used the correct clay based grease in the calipers.  Is it better to try flushing them out with the correct grease or leave it and just use the correct grease going forward?

Thanks in Advance,
Al Anderson

[Steve Huber Co-Admin]

Al,
The link to the Meritor M4 manual is in Coach Assist on the Private Members Only board. It is under Beaver Equipment Manuals.
Steve

[Gerald Farris]

Al,
When replacing a wheel hub oil seal, I always remove the oil seal and take it with me when buying a replacement, therefore I have never written down the various part numbers. To remove the drive hub, you will need a 4 inch socket to remove the spindle nuts. I use a 3/4 inch drive one on a 3 foot long ratchet, and I have never had a problem with the lock nut. However if you are not familiar with drive axle repairs or do not have the proper tools, you might consider having it done by a professional, but only one who is familiar Meritor ADB brakes. Very few trucks ever had Meritor ADB brakes, so truck mechanics have rarely, if ever worked on them. They were mostly used on Fire Trucks, Tour Buses, and RVs. 

When it comes to brake pad part numbers, there are many options depending on whether you want pads for one or two wheels and how severe your operating conditions (temperature) are. Also Meritor changed their part numbering system a few years ago, so there are still a few of the old part numbers around (S2R7017173). For your coach there are 3 service levels of brake pads in an axle set (2 wheels) that run from Kit15625PM, Kit15626PM, and Kit15627PM with the higher numbers being for more severe service conditions and at a higher price level. The single wheel kits are Kit15615PM, Kit15616PM, and Kit15617PM, if available.

When it comes to caliper lubrication, my suggestion would be to lubricate all calipers, using the proper grease, and following the exact lubrication instructions listed in the Meritor service manual. These lubrication instructions will purge some of the old grease and lubricate the piston and shaft to insure proper operation. I lubricate my Meritor calipers about every other year. This schedule is about right for the drive axle and probably a little excessive for the front and tag axles since Meritor states that the calipers should be lubricated twice in the life of the pads and I drive about 15,000 miles annually on average.

Also, when servicing your Meritor ADB brakes, my suggestion is to always install caliper return springs as per the Meritor Technical Service Bulletin, if they have not already been installed or if they have been damaged from excess heat. The part number for the spring kit for one wheel is Kit15018, and they are only sold per wheel (2 springs), so you will need 6 kits for a tag axle coach.

Gerald     

[Pat Long]

What Gerald says Is Good Advice but to get to the spindle nut you will have to remove the drive axle itself.  If you have never done this it can be quite a stressful job.  You probable have the Rockwell drive axle and if it were me in your situation I would search on Youtube drive axle removal and see the procedure step by step.  I have done both Eaton and Rockwell and have found the Eaton an easier job.  Start with youtube and see if its a job to tackle.  And as Gerald has stated Don't Forget the Update Springs KIT15018, for the Caliper return to neutral position, eBay is the best price on all the parts mentioned.   I would stay with the KIt15625 pads

[Mike Shumack]

Pat what is the difference you are talking about with the drive axle removal between the Eaton and Rockwell?
As a retired heavy truck mechanic, I have removed many drive axles over the years, and I don't recall any differences or difficulties (maybe it's due to age related memory purging).

The basics are to remove the axle retaining nuts then whack the center of the axle with a large sledge hammer to loosen the tapered locks. The sledge hammer (or Tool) shocks/bounces the axle shaft which makes the tapered locks pop-out/loosen. Then you slide the axle out (and have a oil catch pan ready under the hub).

There are tools available, like this (but I have never used one). Although if you miss hitting the center of the axle with the sledge and hit one of the axle shaft retaining studs, you will have wished you had the tool. 

[Al Anderson]

With regard to removing the axle/cover for the dually wheels; once I removed the bolts, I simply tapped on the cover with a brass hammer and the conned shaped spacer popped out on their own.  I was able to use a soft drift pin to knock the lock nut off but have ordered a four inch socket for the reinstall.

Thanks everyone for all the help.