Need to replace trailer airbag - where do I find the spec?

I have a 2003 Great Dane 53 ft dry van with sliding tandem. The left very big air spring is leaking and needs to be replaced. I agreed with my mechanic to obtain the air spring and he would replace it.

I fear it might be hundreds of dollars so I would like to do what I can to shop around. So I would like to find out the part number for it so I can shop around for prices, rather than just calling some full service place and feel obligated to buy whatever they offer.

However I cannot find ANY web page where I can enter my trailer VIN and get specs for my trailer. Not even on Great Danes own web page. Their web page just tells me that if I have a Meritor RFS23T the part number is 21227742, if I have a Meritor RFS25T the part number is 21227892, and if I have a Fruehauf T suspension then the air bag part number is 9394. Well how do I know that? I bought my trailer used and it did not say what suspension option it has in the auction description.

I could drive out to where the trailer is parked and measure or look for type plates and other signs if I only know what to look for.

Any help would be appreciated!!

 

Thanks! The problem is that Great Dane does not have any official dealers in Las Vegas, NV where I live. But I will probably just call FleetPride then, hoping the difference in price may not be that big. Thanks again!

 

Thanks everyone! I went out to the trailer and found a tag with the part number. Also found I needed to replace 3 of them. Ordered them on eBay for $73 each including shipping (new). Fleetpride wanted $170 each.