You have an 88 aerostar with premium sound system but when replacing stereo with after market you need diagram for equalizer booster?
If you replace the factory stereo and the van has a factory equalizer, you will need to remove the equalizer as well. The factory stereo/equalizer package is essentially one unit in two different cases. Neither is designed to work without the other. Best of my knowledge, neither will work without the other.
Hi The Haynes Manual 36004 Titled Ford Aerostar Mini-Vans 1986 thru 1997 2WD Models Page 2A-3 for 4 Cylinders Engines Has A Diagram & 2C-7 for 3.0L V6 Engines Has a Picture Of Timming Chain & Gears. 1 Could Assume Same For 2.8L V6 As for 3.0L V6 & Last 2D-3 Has A Diagram of crankshaft pully & mentions tooth & or teeth for The 4.0L V6 Engines Good Luck