I purchased and received a transmission dip stick measuring device. I just went out to my 2006 Pleasure-Way Sprinter motorhome and tried the dipstick. I noticed that there is no cap or anything on the end of the tube where the dipstick goes in. In other posts I have read about a cap. The dipstick worked fine.

So my question is should I leave the end of the tube open , or buy the cap from a Dodge dealer, or put a plastic bag over the opening with a fastener?

 

Don't leave the tube open. You'll need a cap and a retainer clip that holds the cap on. You can get both of at http://www.europarts-sd.com/get-pdf....247993f8899cbcThe cap
# 140-270-00-91 at $2.65 EA and the cap lock pin # 140-991-00-55 at $.70 EA. I got a few eatra cap lock pins, you can reuse the fill tube cap.