I just had one quick question about replacing the clutch slave cylinder on a 02' Ford F-150 4.2l V6.
The orignal stock part had a rubber boot for a dust shield covering the spring. The new slave cylinder I purchased does not include or mention using the rubber boot dust shield. But they did say it was redesigned and it looks like they built in a rubber dust shield onto the moving cylinder.
Here is a picture of the new one with dust shield
My main question is do you think I need to pull the rubber boot off the old and throw it on the new one? I know it will fit I just dont know if it is required.

http://i602.photobucket.com/albums/tt101/gordon_Gjs/18.jpg

http://i602.photobucket.com/albums/tt101/gordon_Gjs/8.jpg

I wouldn't worry about it too much.

do you think it would have an effect on the life of the slave cylinder?

Ideally you should replace the slave cylinder whenever you change the clutch. So, in essence as long as it lasts the life of your clutch, it should be good enough :)