Gary, just curious but have you dynoed your truck with and without the prefilters on your BHAF? Looks to me like you would have some significant airflow restriction with both of those prefilters. I used an Outerwears cover on my old BHAF for but left it off of my new filter. The only reason I used the cover was for possible water protection. I read somewhere on another website that the Outwear covers do restrict airflow more so than what the advertisements and sales people say. I'm using the Fleetguard AH19004 marine version now and according to Cummins/Fleetguard specs this filters capacity is 825 g per SAE J726. I figure the filter should be good for 2 years in the Texas heat and dust. After that, the filter will probably start to deteriorate anyway.
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2002 2500HD QC Laramie SLT SB; 2WD; Auto; 3:54 AS; Camper/Tow Pkgs; 4" Exhaust; Optima Redtops; Rancho RS9000X shocks; DSS; Isspro EV 30psi mechanical FP gauge; Vulcan 3/8ths LP relo kit to VP44; Mag-Hytec diff cover & tranny pan.