This may be a dumb question...but...

I am looking to put a wider and taller front tire and use skinnier, but just as tall tires on rear, so as to not use spacers...( or perhaps as little as possible)

Want to keep the wheels (stock 16") Since it is 4WD, it is my understanding that the diameter of the the tires need to be the same, but not necessarily the width...Is this correct?

Are there tire combinations out there that will work for this?

You are correct as long as they are the same diameter the width does not matter, I cant remember the exact max diam difference you can have front to rear but it is very minimal for 4wd.

You can do 235-85-16 in the rear and 265-75-16 in the front.
Use this link to answer all your tire size questions. http://www.discounttire.com/dtcs/infoTireMath.dos

I put 245-75-16's on the front and 215-85-16's on the back. After several thousand miles of towing my fronts still look new. Before I switched, the truck was eating the front tires like crazy.
Dave

I put 245-75-16's on the front and 215-85-16's on the back. After several thousand miles of towing my fronts still look new. Before I switched, the truck was eating the front tires like crazy.
Dave
Glad to hear your success...I have the same issues with my fronts and have decided to just change the fronts to 245-75-16 and rotate side to side and keep the rears at 215-85-16...according to my tire guy, i gain over an inch in width and only about 3/16" difference in overall height...he said that was negligible...

Thanks for the comments...

If you wanted to go bigger yet there is 285/75-16's and 255/85-16's

Its .24 difference in overal diameter, so less then 1/4". and 614 vs 610 revs per mile.

I

woops
I'm running 265\75\16 and 235\85\16
works good almost 2" wider