Here is a post that I did years ago. Hope this helps.
If there is still a sticker tag in the center of the lower carrier facing towards the rear, your in luck for making sure that you will get the right parts from ACE. If you still have that tag in place, record the number with your other information for your coach. This is a link to American Carrier Equipment in California. American Carrier Equipment - American Carrier Equipment, Inc. Home Not much of a web site for them. To get information and ordering parts, best way is to call:
American Carrier Equipment, Inc.
2285 E. Date Ave., Fresno, CA. 93706
If you are going to work on this unit, For $2.00 or so BUY THE SERVICE MANUAL!!!
Also they are called American Carrier Systems ACS.
My unit is 8015 and is superseded by Model 8050 (same components)
Here is a shot of the location of the Serial number tag:
Here will be some of the components that we will be working with:
You can purchase all that is needed from ACE, manuals and parts, but I purchased the Firestone bags from Truck Suspension, Bilstein Shocks, Firestone Air Bags, Timbren, Leaf Springs - TruckSpring.com
The Firestone air bag number from Truckspring.com: W01-358-5412
ACE Part number: 8003-011
One of the problems I have seen in other forums is that some people have listed the wrong air bags for people to get. The bags needed for our rigs have an internal stop to keep you up if for some reason you loose air. Also while setting, the system as it looses air will rest on these internal stops.
With this system on the P30 chassis, it has a system built into it that will keep the rear from wagging. If the Transverse Rod Bushing and Straddle pin get worn, you could have a wag!
You can replace these without taking down the spring beam. I removed mine so that I could check all the bolts, clean and paint.
I have seen some of the spring beams broken, and would place a bet that someone has drove the rig with out good air bags or no air in the bags. When Airstream place this unit on our rigs, they cut off the back side of the springs leaving them almost like a steel bar for a suspension with out the air bags not working. Airstream recommends that we not go over 40 mph if the air bag system is not working right (no air etc.). So keep your air bag system working properly or you will have many other problems that you don't want.
Here is some replacement part numbers from ACE:
4 needed of 7572-102 Transverse Rod Bushing
2 needed of 5506-001 Straddle Pin
2 needed of 8003-011 Air Spring or (Firestone Bag as talked about earlier)
All bolts should be OK. If you want to replace bolts and nuts, replace with only the recommended Grade of bolt. Most American Standard bolt markings on the head are as listed: 3 marks will be a Grade 5 bolt, and 6, Grade 8.
Here is a shot of the Transverse Rod when bags are down, and when they are to height.
Notice how the air bags are also inflated. First is with 40 lbs. of air, they start picking up the coach at 70 lbs. The Height Control Valve shuts off air supply to the bags just under 80 lbs.
I think that Airstream recommends to only travel at 40 mph (as talked about earlier) if not inflated to operating pressure. My compressor is set up kick in at just under 80 Lbs and out at 90 lbs. I have tried to hit 100 lbs, but the compressor don't like it.
As you see in the photo the pins and yellow neoprene bushings with steel washers backing them. Paul told me if the washers are loose from the bushings, they should be replaced.
Before replacing anything on this carriage, you will need to block up the axle to the frame. Measure the height while the bags are inflated, (if they are working) then cut a block or crib 2x4 or 2x6's to allow all the pressure to be removed from the air bag carrier. You can also use some heavy jack stands to place under the frame to the floor for extra protection.
To remove the spring beam, first place a jack under and about the center, and make sure all pressure is off the unit. Remove the linkage to the air valve, using two 7/16" wrenches. You will be removing bolts out the bottom for the air bags 3/4" socket, bolts for the pins holding in the straddle pins 5/8" wrench and socket, and the end bolts of the spring beam to the shackle 3/4" wrench and socket. The all tread rod going into the air bags might come out completely, that will be OK, but there are two nuts on the end of the all thread up inside the spring beam. It would be OK to remove all the bolts for the straddle pins.
The bolts in the shackles, could interfere with the tire. Mine just made it past them with a little force. Remember this spring beam is heavy and you do not want it dropping on you, BE CAREFULL!
After you have the spring beam down, you can first remove the air fittings on the top of the air bags. There will be two 3/8" bolts on each side of the air fitting holding the air bag. Using a 9/16 box end or short ratchet, remove the air bags from the top frame. Do not damage the air fittings.
If not removing the spring beam, remove the air bag bolts and the bolts holding in the straddle pins. If the all thread rod stays in the air bag, after you remove the top bolts and air fittings, you will be able to move the bag to clear the threaded rod.
The bushings in the transverse rod should come right out. If the metal backing plates were loose, they are already off. You will see the new ones are molded on. The bushings will come right out of the transverse rod and new ones will go right back in. You will see the pins look worn at where they contact the bushings. Good rule of thumb is while your are at it, don't skimp, replace both pins and bushings.
After replacing the bushings you will be able to bolt the transverse rod, bushings and pins right back in place.
Replace air bags in reverse order you took them out. When connecting the air fittings, make sure that you keep the fittings clean and check for leaks.
The top bolts of the air bags, oiled 20 ft. lbs. ( I could not get a torque wrench on the bolt heads just as tight as I could with my Craftsman 9/16 box end wrench.
Bottom all thread rod: Use Loctite No. 271 on the end that goes into the Piston (bottom bag mount).
On bottom of all thread rod going through spring beam, first 1/2" SAE flat washer
Then 2, 1/2-13 NC Hex nuts on each rod. Torque the first nut to 55 ft. Lbs. Oiled.
Place second nut on and do not exceed the same torque.
If you have taken down the spring beam, the shackle bolts will torque to 130 ft. lbs. Oiled.
Straddle Pin bolts, torque to 55 ft. lbs. Oiled
The new air valve used: Lear Siegler Inc. Neway Division 90054007 or 90054387
Airstream Air Bags DIY.doc