Front Air Bags on R4R-A Roadmaster Chassis (2005 Cheetah)
Well I finally got to replace the front air bags that initiated this post. That you all for the helpful suggestions that made this project less of a pain in the A**.
In the process I discovered a few techniques that made the project easier and I want to share them. While every chassis and air bag set up is different for those working on a 2005 R4R-A Roadmaster this may be helpful.
1)Safety - Not being a regular mechanic laying and working under a 39K motor home can be a bit unnerving. I spent the $100 and bought a pair of 12 ton jack stands from HF to support the coach. Used the leveling jack to raise the coach, then placed the jack stands and released pressure on the jacks. Easy peasy.
2) Compressing the air bags is much easier using ratchet cargo straps but once compressed and in place, the straps can be a real pain. I found that once compressed and partly in place I had to remove them to get the straps off. I found it easier and quicker to compress with the strap and then hold compressed with both hands and put in place from underneath the chassis.
3) The original air bags for this chassis had a 3/4" FPT air inlet. The new ones have a 1/4" FPT air inlet. The connection to the air hose is not standard. As a result it is best to re-use the 3/4" brass adapter from the Original bags. In order to do this I used a 3/4" to 3/8" bell reducer (also brass) and a 3/8"X1/4" male-male pipe thread reducer (also brass). It was not recommended to use teflon tape but pipe dope to insure a good air seal. Lastly, if you install this adapters prior to installing air bags you will likely not be able to get enough compression of the bags to make them fit. I learned the hard way that installing the bags on the chassis first and then installing the air adapters was much easier.
4) The Automan 9551 air bags I got arrive with a different bold pattern than I needed. The solution I found worked best was to first adjust the piston (bottom) bolt pattern as close as possible before install. Do not tighten the center bolt that holds the piston to the bag until the bag is in correct position on the chassis, This will allow for minor further adjustments as needed. Once in place, the center bolt can be fully tightened using a 3/4" offset box end wrench from underneath the chassis.
5) Using a bottle jack to raise the bottom plate in setting the bags was a real help. Note the top bolts and outside bottom bolt can be easily set in place using a deep socket 11/16" ratchet, but the bottom inside bolt is a very close fit. The only way I found to tighten the nut was to use a 11/16" open end wrench. Here again the bottle jack was helpful in getting the bolt in a position that the nut can be started on it.
6) Lastly, the 4 nuts that hold the bags in place have been doing so for a long time. Impact wrenches probably wont fit. I found it worth the $15 to buy a 1/2" socket breaker bar (also from HF!) and penetrating oil spray made getting these free much easier.
Sorry I have no pics. Maybe I can take some today and post them. Next project is greasing the front of the chassis and then I will re-park the coach so I can do the back. I hope the above information will be helpful to others taking on this project.