I'm now getting what i'd describe as a 'spinning rattle' from driver's side of the dash. it's very interminit and only seems to happen above 40 mph and will do it for a sec or 2 then not for a while-although it has gone longer on occasion. besides the heater stuff what is there mechinical under the dash. I'm thinking speedo cable but i do not know if it's mechinical or electronic. this is on a 98, 2.5L stock.