TCMDOC
New member
The stock 4Runner pipes are actually metric and the closest match is 2.375" outside diameter 2.25" inside diameter. The tailpipe flares out a little bit for the last 4 inches only. As long as you use stock pipes, the 2.25" or 2.5" muffler should be fine (no loss of low end torque). I put on a custom mandrel bent 2.5" outside diameter tail pipe on my 4Runner with a magnaflow and lost low end torque. I quickly changed back to stock.
Since the 4Runner's pipes are 2.375", I recommend the use of a 2.5" muffler and stock pipes.
i know this thread is a lil old, but i just didnt want to steel anyone elses thread, so i figured let me look, first, so i found this ad on CL
flowmaster 44 series muffler
and i was just wondering if this would be a problem, since i dont know the size of the pipes if the exhaust tubes, and by seeing your previous post i dont think it will be a problem,, but please anyone can let me know, im riding a 97 4runner SR5 automatic. like to have that nice rumbling sound.