Our Dodge Ram Vans do not have the luxury of a trip/fuel gauge like most of the Dodge Caravan's do. BUT, this little jem does so much more than that.

This display is really amazing in itself.

It will report in REAL TIME what the vehicle is doing.

Want REAL TIME data on how your drving to save on fuel? This baby can do just that plus so much more.

A USA Today article written about hypermiler's talked about this device. Just changing your driving habits while monitoring the gauge can give a significant boost to your vehicle's mpg.

ScanGaugeII - The 3-in-one Automotive Computer

It plugs right into the vehicle's OBD-II port and reports REAL TIME information. This port is located in the lower part of the dash just above the brake pedal. Easy to reach and locate.

OK, without sounding like some dumb sales person, the link here shows all of the features.
http://www.scangauge.com/features

 

I use one of these in my 96 B3500 and it works extremely well. It lets me tune my driving habits such that I've been able to average up to 19 MPG in some cases (and this is with a cargo box and bike on the roof, and in the mountains). It also provides helpful diagnostic info and can read trouble codes. It's only been a couple of months, but I don't think I could drive without it now

 

How new does the truck have to be for ODBII?

(4 hours later)
Nevermind, I had a chance to read the page, 1996 and newer.
I'm out of luck.