Hi. I drive a 1990 240DL station wagon. Lately,the transmission has not been going easily into 4th gear, causing me to stay into the slow lane, sometimes for miles, until it kicks in. I tried checking the transmission fluid levels per the owner's manual, but still found it confusing whether it needed the fluid or not. (If the stick shows simply "wet" with engine running, does that mean it's full?) Just in case, I added about 1/3 quart of transmission fluid, and will have to see if it makes a difference. Meanwhile, what are the signs that the transmission itself is going? All the other gears seem to come in fine. ALSO: I have been using the cheapest grade gas for quite a long time -- will this cause trouble somewhere down the line? FINALLY: I admire all of you who seem so knowledgeable and able to do so much of your own work on your cars. I am not so able, or brave, and for financial reasons, basically just take the car to the mechanics when something clearly seems to need attention (screams for it?) I bring it to local, well-reputed, general mechanics (i.e. not Volvo specialists). I bought the car 4 years ago, with 78,000 miles, from elders who maintained it impeccably. THe odometer broke with me at 84,440 miles, and other than periodic oil changes and fluid checks, I have missed all those other scheduled maintenances. Am I dooming this car? Any advice on any of this, especially the transmission issue, is already appreciated. Thanks for being out there. Ms. MM Bosco822@aol.com.