I had something similar happen to me recently, only my entire FWD was out - sounded horrible in turns. The TOD computer is separate from the ECU and has to be read from a OBDII scan gauge that can read ISUSU specific codes - I went to the dealer for this (cost me $95) and they told me that both TOD speed sensors were bad - wanted $1200 to replace them. I found them at St. Charles for $319 each. I've got a write-up about the experience and install on my blog: http://vehicross.blogspot.com/2007/0...ercharged.html

I'm not saying that what happened to me in regards to the TOD is happening to you guys, but offering my experience with the situation - especially about the lack of codes.

-- John