I'll do this starting at present and go back in time - Driving tonight the heater stopped working - blows, but cold. Online research suggested low coolant. A few weeks back had timing belt replaced, mechanic told me I was low on coolant and he topped it off at that time. Few weeks before that, told same thing (low, they filled it up). 1 April I replaced the radiator, and now since then I keep going low on coolant. Here's the thing, there is never any fluid on the ground, but the other day I thought I smelled something odd from the front after driving for 45 minutes. Made a mental note, but forgot about it til tonight, when the lack of heat brought me back to 'low coolant.' The only other distressing thing is since the timing belt was replaced, the trans has been shifting hard, between 1st and 2nd and sometimes 2nd to 3rd. Occasionally 3rd to 2nd too. Does anyone want to hazard a guess at either why the coolant is going low, and whether any of the recent work could be contributing to any of these symptoms? Hubby just left for work travel, thought I'd see suggestions I might get from this forum. The trans was replaced 2 years ago, still under warranty, just haven't taken it back to them yet with recent shifting concerns. Worried they would say somehow the timing belt work is at fault, but I digress...