Air Brake Filter

[Ragman]

I have a 2001 Tradewinds with a 330 CAT and planning to replace the air brake filter that sits quite high above the slobber tube. (Hard to get to.) My filter is about six inches wide and 6-1/2 inches high and is quite heavy.

Has anyone replaced the filter yourself? I could use some guidance with this. Should I just replace the filter or remove the whole system (including the slobber tube) and replace it on the workbench?

Thanks.

Happy Trails,
Larry

[bdpreece]

You need to get under there and clean everything to see if there is a name or number on the filter. I spent a lot of time trying to get mine off (04 National Tropi Cal Cat 350)as I thought I had one that came apart like a spin on canister. I finally found out I had to remove the lines and take it loose at the bracket attached to the frame rail then just drop it down and put it on a bench to disassemble. Really not that hard once I figured out what I had. I sold the coach so all the paperwork went with it. don't remember what it was now.

[chasfm11]

I've worked on ours several times. First, I'd agree with the other poster that you need to figure out which of the several brands of air filter system you have. Haldex is a common one. I don't know for sure but I thought National was on a Freightliner chassis and, if so, you can contact FCC for parts information. I even buy my air filter kit directly from FCC in Gaffney, SC.

2nd, I'd agree with cleaning up the area all around the filter. The last thing that you need to do is bump something and knock debris inside. On mine, I can contort my way to a sitting position. I take a strong light with me and shine it on to the area, making sure that everything is clean.

I needed a strap wrench to loosen the filter and found a set of strap wrenches at Sears. On mine, after a I get the spin on filter, there is a coelessing filter under neath of it. One time, I had wet contamination under the coelessing filter and needed lint free clothes to clean it out. After that, it was just reassembling things. The first time that I did it, I replaced the exhaust valve and the input heater cap. This last time, I just keep those parts for future use. On mine, to remove the exhaust valve, I had to loosen and rotate the filter assembly.

I'm never a big fan of taking more apart than I have to so if there is a way to work on the unit without disconnecting the hoses, that is the way that I would good.

BTW, be sure to use the lanyards on the air takes to bleed down the air pressure before you take anything apart.

[bob109]

Quote:

Originally Posted by Ragman I have a 2001 Tradewinds with a 330 CAT and planning to replace the air brake filter that sits quite high above the slobber tube. (Hard to get to.) My filter is about six inches wide and 6-1/2 inches high and is quite heavy. Has anyone replaced the filter yourself? I could use some guidance with this. Should I just replace the filter or remove the whole system (including the slobber tube) and replace it on the workbench? Thanks. Happy Trails, Larry

This info may help depending on the type of chassis you have

Air Dryer Maintenance

[movin-on]

This may help also...Although it is for a 2004 Freightliner chassis, it is exactly the same on my 02 Freightliner chassis...It is for a Haldex Pure Air Plus dryer...

DiscoveryAirDryer

[OneRVer]

I am pretty good doing somethings on my motor home. Saying that I do take caution with somethings that I have never done before. My dryer/filter is located just behind and to the left on my right rear duels. When I went to replace it something bothered me. I have never done this before. So what I do when I get worried about what I am doing or going to do, I will take it to a shop and watch what they do so I will know how to do it the next time. Well this is one item that I am glad that I did. Took about 75 mins to get the darn thing off. Then there is more then just the filter. It had an inner and outer filter plus o-rings and other parts and pieces. So anyway I am glad I took her to a shop and I will be darned if I can remember what all had to be done in the first place.

So good luck. I will be wondering how yours went.

[chasfm11]

Quote:

Originally Posted by OneRVer I am pretty good doing somethings on my motor home. Saying that I do take caution with somethings that I have never done before. My dryer/filter is located just behind and to the left on my right rear duels. When I went to replace it something bothered me. I have never done this before. So what I do when I get worried about what I am doing or going to do, I will take it to a shop and watch what they do so I will know how to do it the next time. Well this is one item that I am glad that I did. Took about 75 mins to get the darn thing off. Then there is more then just the filter. It had an inner and outer filter plus o-rings and other parts and pieces. So anyway I am glad I took her to a shop and I will be darned if I can remember what all had to be done in the first place. So good luck. I will be wondering how yours went.

Maybe it really was that hard.... or maybe the tech who was working on it was doing so on the first MH that he had ever seen.

Let me tell you a story. On many of the Cummins ISBs in the early 2000 range, Freightliner put on an A/C belt that was too small. To compensate, they removed the adjuster on the compressor from its proper location and mounted it under the compressor. There is no way that the belt that size will go over the fan blades. Many Discovery owners took their RVs to dealers to have the belts replaced. The techs removed the fans and charged $350 for the job.

THe real "fix" is to cut the old A/C fan blade off, remount the adjuster veritically on the inside of the compressor and buy a belt tha is about 2" larger than the original A/C belt. With that change, it is easy to put both belts on. It can take about 10 minutes. A shop that charged an hours labor was still taking advantage of the situation.

I can understand that, if you don't have the proper sized strap wrench, the air brake filter might be hard to take off. It is also possible that the proper lubricant was not use on the o-rings when it was installed or that the type of air filter is different than I have seen. I cannot imagine one that hard to get off, however. It is nothing but a cannister with central threads. Worst case, you can punch a hole in the side and stick something through to give yourself some leverage.

[Ragman]

A BIG THANK YOU to everyone. You gave me the courage to tackle this job. It wasn't as difficult as I had thought and I didn't realize how necessary it is to keep your air lines in a safe condition. Tonight I will try to post exactly how I did it when I have more time. Thanks again. You're always such a big help.

Larry

[RV'nOldTimer]

Quote:

Originally Posted by Ragman A BIG THANK YOU to everyone. You gave me the courage to tackle this job. It wasn't as difficult as I had thought and I didn't realize how necessary it is to keep your air lines in a safe condition. Tonight I will try to post exactly how I did it when I have more time. Thanks again. You're always such a big help. Larry

I am (over) due an air dryer/filter change, so i went by the local Freightliner place with my unit's serial number and they looked up my chassis on their computer and sold me the kit -- part number HDX DQ6026 -- $152.83 plus tax. Ouch, but ok, we're on the way.

At home, I find that none of my filter wrenches are large enough, so I measure the new desiccant filter and order a new heavy duty strap wrench to handle the five inch diameter filter. This afternoon I got around to tackling the chore. Cleaned up the site, exhausted the air tanks, and tried to get the wrench on the filter. Wouldn't go, so I made a little more room around the top area by cutting some cable ties to shift some large cables that were above the filter. Still, no joy. The wrench wouldn't fit, so I measured the filter by cutting a string to its circumference and comparing it to the new filter. Remember, the new filter is five inches + or - 0.1 inch diameter, the filter on the MH is 6.1 inches, so this isn't going to work. Good thing the wrench didn't fit 'cause the new filter obviously isn't gonna fit. So I buttoned things back up and will make another trip to FL.

Anybody have any idea what filter is really on the MH? I can read the letters PUR on the label, but its not the same size as the part sold to me and cited above. Other than this difference, it looks the same.

JT

[Dick1142]

I haven't changed mine yet, but I bought the OEM replacement filter at NAPA. Was only $27, which was a buck cheaper than the NAPA (wix) replacement. Hopefully it is as it looks, and just spins off and on.

My filter is a Wabco R 950011 or a NAPA 4374 (it is about 6" around, and black in color)

[Dirtbuster]

I just changed mine Tuesday. There are 4 bolts on the top of the canister. I think they were 15mm. Remove the bolts, & lift the top filter housing off. Inside you will find the replacement desiccant filter. Push on the filter CCW around a 1/4 of a turn. Turn the housing over & the filter will fall out. Put the new filter back in, & install. Directions should be inside of the box. My filter was a different number. Called Freightliner to verify new number, & they said it should fit.

I removed the complete unit. Took 3 bolts off of the frame, & removed all of the air lines & 1 electrical connector. Make sure you drain all of the air off off of the air system, before removing anything. There is a schrader valve on the bottom of the dryer, to verify that the air is gone. This should not take more than 30 minutes to complete!

I hope that the 27.00 filter at NAPA is not the same. Ouch is all I can say!

[wagonmaster2]

Quote:

Originally Posted by Dirtbuster I just changed mine Tuesday. There are 4 bolts on the top of the canister. I think they were 15mm. Remove the bolts, & lift the top filter housing off. Inside you will find the replacement desiccant filter. Push on the filter CCW around a 1/4 of a turn. Turn the housing over & the filter will fall out. Put the new filter back in, & install. Directions should be inside of the box. My filter was a different number. Called Freightliner to verify new number, & they said it should fit. I removed the complete unit. Took 3 bolts off of the frame, & removed all of the air lines & 1 electrical connector. Make sure you drain all of the air off off of the air system, before removing anything. There is a schrader valve on the bottom of the dryer, to verify that the air is gone. This should not take more than 30 minutes to complete! I hope that the 27.00 filter at NAPA is not the same. Ouch is all I can say!

Dirtbuster,
Did you just remove the top part of your dryer to replace the cannister inside, or did you remove the whole dryer to work on it outside on a table? I did mine a couple of years ago and it was so tight working above the axle that I removed the mounting bolts but in no way could I get the push/pull air hose connection apart so had to let the unit hang on the hoses while removing the 4 bolts and the top part of the filter while laying under the back end of the coach, not a very nice experience. But thankfully I did have a good helper who is a qualified auto mechanic.

Wagonmastee2

[Dirtbuster]

I removed the whole dryer assembly. On my coach there is only one fitting to break loose with a wrench, and the 2 plastic lines with quick connects. Press in on the connector where the hose goes into, & pull the hose out. Pretty simple if you have removed the hose before. It is the same type quick connect used on the pex water piping.

If you did not remove the whole dryer, a 15mm ratcheting wrench should work pretty good.

Hope this answers your question.

[wagonmaster2]

The air hose with the push connection was the one giving me problems, it wouldn't budge at all, and that was the first time it would have been removed. Is there something special that needs to be done the first time?

Hoping by the time the next filter change comes around I'll have been able to figure out how to remove it. Working on all that under the back of the coach still hooked to the two main air hoses was no fun.

Wagonmaster2
2004 Meridian 36G