I've been running a 19 toother for around 5 or 6 thousand miles, and lately I'm thinking of changing to an 18 as it's a little easier on the driveline and engine on startups.
As a former truck driver, I have many years of the gospel: "In or out - do NOT slip the clutch" on the brain, and the 19 wants a little slip to launch smoothly. If I don't keep that slippage in mind when launching the 19, I get a little bucking in the engine, which is probably grinding some metals into the oil. Depending upon the grade, it sure is nice to shift into 5th at 60 or 70 MPH though, as is the case with the 19.
