2008 ram did not come with a cab air filter but it can be retrofited where is the cabin filter on 2008 a jeep liberty.
													
																	2008 dodge ram cabin air filter location. 
									
	
		
	
																	Turbo diesel crew cab pickup 4 door this video shows you where the ac filter pollen filter or dust filter is located in a 2008 dodge ram 3500 st 6 7l 6 cyl. 
																	Check the condition of the cabin air filter in a 2008 dodge ram 3500 st 6 7l 6 cyl. 
																	Turbo diesel crew cab pickup 4 door. 
																	The cabin air filter in a 2008 dodge ram 1500 is located beneath the dashboard on the passenger side. 
															
													
									
	
		
	
																	After you remove the cowl there will be a grey accordion looking filter in the cowl remove that and replace with the new filter. 
																	After opening the hood remove the windshield wipers and the black covering 2 small t 30 screws and a few body grommets. 
																	Hello i do not know if is relevant but for 2008 2013 caliber and 2008 2013 caliber srt4 the cabin air filter is located under the glovebox.