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vettenuts · 07-26-2021, 03:16 PM

After a lot of searching I have finally found my air leak, both front air bags are leaking where they roll upward on the bottom stem. Minor leak, takes time for bubbles but they are definitely leaking. So now I am pondering the solution. I will have the coach near Josam Frame & Alignment in Orlando next spring and could easily have them do them while I get my alignment but they are 1,200 miles away. The other option is to attempt them myself.

I have watched several videos and the range of replacement went from disassembly of the axle mounting to making a special 1-1/8" wrench to get the bottom bolt out by cutting a socket down and welding it to a flat bar.

I have also downloaded the Freightliner service manual but it is almost useless as it is poorly written and doesn't address all the fasteners I know need removal to change the air bag.

Hoping maybe someone has some documentation or a DIY they can share on swapping these out. I don't plan on using the coach for travel until after the holidays when we head south so I do have time to work on it.

JNSNWT · 07-26-2021, 03:33 PM

I’m not sure what chassis or year you are working on but I replaced all 4 bags on my 2001 Freightliner XC without any problem.

Just a nasty job.

vettenuts · 07-26-2021, 05:28 PM

Second question if hopefully someone knows, my leaks are minor and coming between the air bag itself and the bottom plate/stem. From drawings I am finding, it appears that this is the clamping plate. I am wondering if my air bags themselves are okay but the clamping load needs to be adjusted, which I believe is the large center nut in the bottom of the air bag. Does anyone know if this can be done?

ftodaro · 07-27-2021, 07:26 PM

Quote:

Originally Posted by vettenuts

Second question if hopefully someone knows, my leaks are minor and coming between the air bag itself and the bottom plate/stem. From drawings I am finding, it appears that this is the clamping plate. I am wondering if my air bags themselves are okay but the clamping load needs to be adjusted, which I believe is the large center nut in the bottom of the air bag. Does anyone know if this can be done?

If your getting leaks in the bags they need to be replaced. Its not worth taking a risk of failure on the road. I replaced my Air bags myself also, and i did it by dropping the front axle.

Had i seen the post on making the wrench (this was after I did my bags) I would try that first. Dropping the axle is work and need need a good impact to bust the nuts loose. Otherwise the project is not difficult if you have a safe place to work and have time to do it.

vettenuts · 07-28-2021, 05:19 AM

Thanks for the response. My reason for asking about the clamping loads on the bag bottom seal is because some bags come as a complete assembly and some with the top plate attached to the rubber bag itself and the bottom plate is reused. So if the bottom bolt is not correctly tightened, they will leak around the bottom seal perimeter similar to what I am seeing. My bags are also not that old and look to be in excellent condition leading me to wonder why I have the leak. However, I am not sure if these particular bags fall into that category.

I do plan on replacing, and am currently investigating a wrench to remove the bottom nut without disassembly of the axle. I have found a 70 degree offset wrench that looks like it might do the job, but it's a roll of the dice because I may not be able to return it. Other option is to make a wrench and we have an excellent used tool store locally that is only open on the weekends. Plan on a visit with him this coming weekend to see what I can find.

Finally, best price on the air bags for anyone in my situation is from Freightliner Gaffney.