Community Forums

crah · 08-13-2012, 11:42 AM

Typically have my chassis lubed at Speedco but recently read that a different type of grease should be used on the air brakes. Anyone have the specifics? The manual only states one type of grease but it also doesn't show every lube point like the hydraulic jacks and there is 1 zerk up in the steering shaft after you remove a plate from below at the floorboard.

Also I tea that the kingpins should be lubed with the weight removed from the suspension. Obviously they can't do that with the pit at Speedco.

walt2137 · 08-13-2012, 12:17 PM

Crag the Sig and Exe that have Disk brakes do take a clay base grease on some if not all but our old style air brakes just uses regular old grease just be careful on the zert that injects grease in the brake chamber, only a couple shots of grease there. Thats all I have used for over 10 yrs.

Mike Canter · 08-13-2012, 02:30 PM

Not sure I can agree with you about that. First there are no grease fittings on any disk brakes on my Sig. I do have grease fittings on the slack adjusters on the drum brakes on my tag. Those slack adjusters require clay based lithium grease vice soap based lithium grease and I am pretty sure all slack adjusters on drum brakes on airbrake systems require clay based lithium grease. The problem is either people don't know that or don't care. I think this is an important subject because you don't want grease on your brake linings, you don't want your slack adjusters to freeze up and the clay based grease is not compatible with soap based grease. (

crah · 08-13-2012, 03:16 PM

Interesting. I wonder what most people do? I have the 4 drum brakes and I should have said the slack adjusters. I wonder if a place like Speedco know that and actually change greece guns?

walt2137 · 08-13-2012, 04:14 PM

Quote:

Originally Posted by Mike Canter

Not sure I can agree with you about that. First there are no grease fittings on any disk brakes on my Sig. I do have grease fittings on the slack adjusters on the drum brakes on my tag. Those slack adjusters require clay based lithium grease vice soap based lithium grease and I am pretty sure all slack adjusters on drum brakes on airbrake systems require clay based lithium grease. The problem is either people don't know that or don't care. I think this is an important subject because you don't want grease on your brake linings, you don't want your slack adjusters to freeze up and the clay based grease is not compatible with soap based grease. (

Could be right Mike, I have never used clay base on any of our coaches slack adjusters and I have always did all of the service but I do remember the Sig owners on MCOA discussing the clay base for the Disc brake calipers. Sure wont hurt anything to use it.

Downsizer · 08-13-2012, 04:20 PM

On the disc brake calipers, you are supposed to be lubricating the slide pins - there is no "grease fitting". You just want the caliper to be able to slide within it's bracket.

Dutch Star Don · 08-13-2012, 05:34 PM

I know my manual says to use the clay based grease. I'll admit, I never have. I use a quality grease and I'm carefull to give the slack adjusters just 2-3 quick squirts. The first time I lubed the coach, I pumped them full and had a hard time getting the brakes to release.

By the way...the steering column has three fittings. One is obviously down low, one is halfway up the shaft and difficult to get to from the generator bay and one you have to remove the plastic cover from around the steering column (inside the coach).

Mike Canter · 08-13-2012, 05:42 PM

I wish k knew why it has to be clay based. My guess it has to do with the high temps. Because soap and clay based are not compatible my recommendation is if you have been using the wrong one then do not switch now. Stay with what you have been using.

slickest1 · 08-13-2012, 11:22 PM

I have used just regular old grease on slack adjusters, u joints, steering components for 35 years and never had a problem. The key is to a regular greasing schedule and to not over grease things like brake cam bushings which will cause grease on brake linings. I have always greased the king pins with the wheels on the ground and never had a problem with worn king pins. Just my 2cents.

Mr_D · 08-13-2012, 11:44 PM

I've been doing my own maintenance for years, never used a different grease on the brakes. Took it it Brazils for an alignment. The tech commented that "whoever is doing your grease jobs is doing a great job, keep him!" Guess I'll keep it up.

Topman · 08-14-2012, 02:22 AM

My manual recommends clay-based grease as Mike suggests to be used on the calipers for the disk brakes. Meritor sells the stuff (0-616-A) and can be ordered from most truck supplies. My calipers have a very specific method on how they are to be greased. Very important it is done right or the brake pads might not release all the way after application.
However the manual also says you can use NLGI grade 1 or 2 clay based grease; Or NLGI grade 1 or 2 lithium-based grease inside the automatic slack adjuster.
Iver.

Mike Canter · 08-14-2012, 12:33 PM

What I understand is that both are the same lithium grease. It is the base that carries the lithium that is different.

crah · 08-14-2012, 12:54 PM

Quote:

Originally Posted by Diplomat Don

I know my manual says to use the clay based grease. I'll admit, I never have. I use a quality grease and I'm carefull to give the slack adjusters just 2-3 quick squirts. The first time I lubed the coach, I pumped them full and had a hard time getting the brakes to release.

By the way...the steering column has three fittings. One is obviously down low, one is halfway up the shaft and difficult to get to from the generator bay and one you have to remove the plastic cover from around the steering column (inside the coach).

Thanks don. I didn't know about the one inside the coach.

Mike Canter · 08-14-2012, 05:30 PM

Ok, see if this helps.I will keep this simple for me. Grease is really oil that is mixed with a thickener base so the oil doesn't just run off the surface that is being lubricated. These thickeners are made of several different things. In our case we are concered with lithium soap and benetonite clay bases that are used as thickeners. The idea is that these bases that hold the oil and make it into what we call grease and melt and flow when heated. This flowing is what allows the oil to get onto and into the bearing surface. A great example of this is wheel bearing grease. If it didn't flow then replacement grease would never move onto the roller bearings so they would never be lubricated and will burn up. The lithium soap base has to thicken again when it cools down or all the oil in the grease will run out. Benetonite clay base is designed to withstand extremely high temperatures up to 900*F and to not melt under normal conditions. Lithium soap based grease melts at a lot lower temperature so things like wheel bearings will get relubricated without having to get too hot. So in our case if you used a lithium soap based grease on disk brakes or on slack adjusters then if you got the brakes warm or hot all the grease would melt and flow out either onto your brakes shoes or pads or out onto the road. So two dangers of using lithium soap based grease on brake components 1. the grease heats up and flows out of whatever it is lubricating so now it is metal on metal and is going to wear, or maybe gall the surfaces and sieze up or will rust and sieze up or 2. will get on your brake shoes or pads. Now you can say you have used lithium soap based grease on your brakes all the time but you can't see inside the bearing surfaces as to the damage that is being done. You maybe lucky and you have never heated your brakes up hot enough that the lithium soap based grease has liquified and flowed out or maybe you have and it is wearing out or will sieze up in the future. I believe that the engineers that designed these brakes and have specified that we use clay based greases know a lot more about this than we do. It is your choice and your MH but I am going to continue to use clay based grease on my brake components.

Air Disk Brakes Lubrication