Hey I wasent sure if it was possibly with different back spacing, but can a stock 17 wheel and tire be used as a spare on a 33 tire and new 17 rim with 4.50 back spacing. Thanks for the help in advance!

 

You should always have a full size, matching spare.
( that means that it is the same as the other 4 wheels/tires you have on)

Depending on when and where you need the spare, it will at the least drive very poorly until the regular is back on and at the worst cause you more problems than just a flat tire.

Safety should always be the the deciding factor when making modifications to your Jeep.
If you cannot afford the 5th tire/wheel, wait until you can.

 

Definitly agree saftey comes first, just heard from a friend that keeping the stock could be an option but with my doubts figured id ask here. All 5 its gonna be then