[rheavn]

Dealing with the front & tag air springs you are working on the outside of the frame rail. Because of the dual tires on the drive axle, the air springs for the drive axle are mounted on the inside of the frame rail. With the tag tire off I was able to inspect the rear drive axle air spring which is the same as the front drive axle air spring. Fortunately inscribed on the air spring was the bellows number 1T15L-2. The bellows number allowed me to only have to consider 16 different air springs. Twelve air springs were eliminated due to the air inlet type & location--down to four. Then two were eliminated by the bottom plate mounting bolts. One was eliminated as it only had a 1/4" air inlet. The one on my coach is the W01-358-9447. I verified with Firestone tech support that it is the proper air spring. I questioned the catalog depiction that showed a bottom mounting stud of only .65" long as mine is longer. He checked the air spring engineering drawing & stated the catalog is wrong and the bottom mounting stud is actually 1.29". The longer bottom mount stud is needed to use a nylok nut.

I called Newell and spoke with Mike Ellis. He stated that he was familiar with the front air springs for the Dana IFS and believed parts had them in stock. He went to parts, pulled one. It matched my description and read the Firestone part number from the label. The Firestone front air spring for my coach is a W01-358-8087. Newell does have the air springs in stock currently. Newell part# 19443.

The air spring ordeal is now done and here are the air spring numbers for my coach. For anyone with a 1998/1999 IFS chassis your air springs are probably the same. A comparison with the Firestone catalog and what is on your coach will verify if yours are the same. Be advised that the front air springs are in this catalog: http://vicbushfield.com/pdf/RV%20Master%...2009_E.pdf
You can do the comparison without removing anything. You just need a tape measure and/or set of calipers.

Front--W01-358-8087
Drive--W01-358-9447
Tag---W01-358-9378

I called Firestone tech support back and inquired as to whether or not the W01-358-8087 was a good and current number. He stated that it is a good number, but is not stocked. Special order only and currently there is a ten week delay. He stated the chances of finding some one other than Newell who had one on the shelf would be nil. He also stated any Firestone air spring distributor could place an order, with a ten week delay.

I hope my experience will help others in maintaining their coach and allowing many miles of happy travels. I do apologize again if I caused any one any frustration with the confusion over the front air bag number. I received information directly from Firestone and passed it on. It proved to be wrong!

I find it odd that Firestone chooses to heavily emboss the PARTS of their air springs on the bottom, but only put the finished part number on a paper label they place on top.