I'm looking for part #s on smc vavles commonly used on air ride suspensions for custom trucks
They use the VX series valves. Get with a local SMC salesperson at 1-800-762-7621 and he can get you more information.
Here is a breakdown of the p/n:http://www.lincolnmarkviii.org/suspension/pdfs/vxd_series.pdfPage 1.Kale
Alkon makes a 4 way spool valve designed and tested specifically for this application