I have a lightly modified 1997 Toyota RAV4 (yes, a RAV4) Here are the mods.

RAV4orce, Magnaflow Muffler 2.25, and Borla Tip, Pace Setter Header, DEI Thermo Wrap, Random Performance Cat Converter, TRD Thermostat, TRD Radiator Cap, Addco Rear Anti-Sway Bar, K&N Apollo Intake filter, TRD Quick Shift, RAV4.1L Front Tower Brace, H&R Springs, Bilstein SPORT Shocks, 2003 Rear Tire Hard Cover, HID Hi and Low beams, Clear front Markers, Rear Reverse Lamps and rear brake lamp, Bomex Front Spoiler, 1998 Rear Taillight, and TRD front Anti-Sway Bar, Yokohama AVID V4s 235/60/16, All Energy Suspension Poly Bushings, Kenwood Receiver, Alpine 40X4 RMS AMP, Infinity Speakers, Infinity Basslink Woofer (200WATTS). Power Slot Slotted Front Disc Brakes, Magnum Hi-Performance Stainless Steel Brake Lines, Twin Derale Engine and Gear Box Oil Cooler, Next Level Performance Tri-Phase module, Front and Rear Spacers 1.25, Nology Spark Plugs and Wires, MSD 6A, MSD Tach Adapter, MSD Blaster SS Coil. Performance Oil Pump, bought, Performance Aluminum Performance Water Pump, bought. Pivot Ground Kit, Pivot Raizin Electrical Stabilizer, DEI Exhaust Rap on Header and 2.25" Pipe. Scan Gauge II, Helix Power Tower Spacer Plate, Grounded Muffler among others.

Please click on link and using headphones. Can you tell me what is this rattling sound.

http://www.youtube.com/watch?v=uPBhjm9fWPE

Thanks for your introducing, Nice to visit your company.

Excuse me, what company? I'm for real.

http://www.cardomain.com/ride/400637

I found it. Looks like the exhaust pipe, which has a flex section. Was wobbling under torque. I added a Chery Bomb Vortex muffler. It lowered the sound and stopped the pipe from vibrating.