One problem related to engine exhaust system has been reported for the 2008 Toyota 4Runner. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2008 Toyota 4Runner based on all problems reported for the 2008 4Runner.
My Toyota 4runner has a consistent ammonia smell that leaks into the cabin. This has gone on for a month and hatch Toyota denies it's a problem. My wife and I fear for our health because of this odor. The forums report this problem as far back as 2003, but Toyota says they are unaware of any problem.