rear gear ratio - tag missing

my 84 dodge swb van rear end tag is missing how can i find out what gears are in it i tried google but no luck

You jack up the rear, put the trans in neutral and turn a tire one rotation and count how many times the driveshaft turns. If you have a sure grip, it's pretty stratight forward.

For instance if you the driveshaft rotates 3.55 turns, you have a 3.55 to 1 ratio.

With an open rear end you need to have someone hold one of the tires and rotate the other one two revolutions while counting how many times the driveshfaft goes around. You can do this by yourself by just jacking up one wheel.

Here is a page with more information. http://www.jedi.com/obiwan/jeep/misc/gearratio.html

3.21s or 3.55s

If you have all of those vehicles listed in your post, you're probably skilled enough to pull the diff cover to see inside. It probably needs a fluid change by now anyway. THAT way you know the ratio for certain.

actually it has fresh fluid thats how the tag came up missing (oops) i also know its stamped in the ring gear but tring to not pull the cover just to find out also im no expert on mopars thats why i signed on to this great forum so i can pick the experts brains and i do have the cars listed but none are restored there just drivers (one day..... ) any ways i need to know the gearing as stock so i can figure what gears i should consider to get a better launch its running 15.1s now with a blown power valve ( didnt have time to fix before the track opened)

Just a helpful tip..... PLEASE PLEASE use some punctuation! It annoys people to have to mentally correct your post so they can understand it. We can be a really helpful bunch, but you need to meet us halfway. Thanks!

Deal!

Type like you talk dude We can all read Not all of us are interested in your written english language communication skills Welcome to the board

i fell kinda honored

There is an ongoing tension over grammar here. SOME are very casual and don't mind reading posts with "less than stellar" English. Good for them. They may be poor spellers or maybe they just don't worry about many things. They probably have fewer heart attacks!
Others on this site prefer to read posts that are clear, to the point and have at least High School quality grammar. The simple truth is, the better your skills are, the MORE members there are that will jump in to offer help. I'll be the first to admit though that there are several members on this forum that do NOT have perfect grammar but DO have excellent skills and advice. Welcome to the machine... Don't be a stranger !