air dryer filter (dryer)

dogvetia · 08-20-2007, 05:47 PM

Our local freigtliner dealer really does not care to work on motorhomes so I do most of the maintence myself-engine oil/filter/fuel filter/transmision filter and lube of chasis. I have hesitated to do the air dryer cannister filters even though it looks to be just a large spin on Haldex filter. any one with thoughts or suggestions on doing it yourself? thanks tom

dogvetia · 08-20-2007, 05:47 PM

Our local freigtliner dealer really does not care to work on motorhomes so I do most of the maintence myself-engine oil/filter/fuel filter/transmision filter and lube of chasis. I have hesitated to do the air dryer cannister filters even though it looks to be just a large spin on Haldex filter. any one with thoughts or suggestions on doing it yourself? thanks tom

**"007"** · 08-21-2007, 07:47 AM

Will short cut your question to FL Forum below may get more answers there.

GaryKD · 08-21-2007, 08:07 AM

My air dryer is just a spin on filter. If you are doing all the other work, this is an "easy button" decision. You can to it too. Just make sure you have all the air out of the system. Drain the tanks manually before trying to remove the filter.

tmitchell · 08-21-2007, 08:22 AM

I changed my air dryer filter in May. It was the easiest one to do on the MH. Make sure you pull the 3 lanyards to expel all the air first.
Tom

tom wilson · 08-21-2007, 09:25 AM

if you have the midland-haldex air dryer there maybe a coalescing filter under the spin on. it can be pulled up and out with visegrips and another shoved down in place.

chasfm11 · 08-21-2007, 10:13 AM

When I did ours the first time, I bought a set of strap wrenches from Sears to break it loose and I bought a "kit" from Freighliner (ours is a Haldex Pureone). The kit had both a new plastic input and an exhaust valve in addition to the desiccant and coelessing filters. The second time I did the job, I just got the two filters. Here is what I found:
1. The instructions recommend cleaning up the area before tackling the job. Mine was a mess. It would be good to not get anything inside.
2. I found that I needed a good light to see what was going on and that, after I got the desiccant filter off, the best position was to sit right next to the filter (coach jacked up and 12K jack stands underneath).
3. There was water under the coelessing filter on the second replacement. I'm told this is normal. I dried it out good with a lint free cloth before replacing that filter.

The job takes me about 45 minutes, start to finish now and a lot of that is setup time (pre-cleaning area, running the light, laying down some cardboard, etc.) I periodically check my tanks and have yet to find any water in them. I think that tells me that the dryer/filter is doing its job. If you do want to replace the exhaust valve, you have to loose the clamp holding the whole filter assembly in place and rotate it about 35 degrees. I'm not sure that doing that was necessary but since it was in the kit, I put it on. I did find that the intake port was damaged by the heater coil so I was glad to change that. It appears that the intake part was re-engineered to add a gasket to prevent that problem in the future. I ended up breaking the intake during removal because the plastic had welded itself to frame.

All in all, this job is a lot more fun to do than changing the power steering fluid, IMHO.

Camping Dutchman · 08-21-2007, 12:12 PM

Go for it, not a terribly hard task, and nothing like the satisfaction of getting your hands dirty!!

wagonmaster2 · 08-23-2007, 05:52 PM

I have been considering doing this job myself also, but my dryer looks like a large can that has 2 halves bolted together. Wish it was just a spin on since I do all the other filter changes without any problem, but this looks like it has to be unbolted from the frame and lowered down to be able to take it apart. Can't even see a tag to know what kind of replacement filter it takes.
Wagonmaster2
2004 Meridian 36G W/XC Freightliner

Cruzer · 08-24-2007, 04:09 AM

OUr 2004 Bus/Freightliner had the Haldex/Midland PURest dryer. It had the design you mention. Yet, the top comes off with 4 bolts to access the desicant cartridge. You don't remove the clamshell clamp as it only houses the turbo protection valve and a few other non-serviceable components. Check out This Link for the service instructions from the Haldex website.

Old Snipe · 08-24-2007, 08:30 AM

I'm scratching my head, went through my FL books and wrote up a schedule for all my service items, but I missed this dryer filter somehow. How often does it need to be changed?

Best Regards!

Pusherman · 08-24-2007, 09:02 AM

Air Dryer Filter Replacement Interval:

For an 07 Journey @ 75k miles or 36 months, whichever comes first.

Cruzer · 08-24-2007, 09:25 AM

Air dryer elements do have service time frames but these vary greatly, depending upon what conditions you travel in. These things fill up from use. If you drive in dry Arizona your dryer will last quite some time but if you travel in a hot humid area it won't last as long. Plus, if your compressor were to start to bypass oil into the air, that too would shorten it's life cycle.

Today's air dryers do a great job of removing moisture from the air. The old pre-trip daily manual draining of air tanks just isn't necessary anymore. However, it does serve a purpose and that is to test the air dryer. If it's functioning correctly you'll see only a slight amount of mist when you pull the tank drain lanyard. Once the filter starts to lose it's efficiency you'll see much more moisture spitting out. That's the signal that it's time to service your air dryer rather than waiting for the calendar to get a specific month and year.