I have a 99 Cherokee XJ and I think its time to install some aftermarket speakers.

Any suggestions? And does anyone know exactly what size they are?

Most audio shops will have that in a look up chart. Why the speakers?

I've always found the weak link to be the deck and lack of sub woofers.

If you want it to sound a lot better buy a good deck that has a built in crossover, and install a 10" woofer and amp.

crutchfield online shows sizes and possible placements as well as j.c.wittney i think.

Pull your stock ones out and take your own measurements.

Those look up charts are BS. They said I needed shallow mount 6.5" speakers,adaptor plates and a special plug to replace my roll bar speakers. Wrong, wrong and wrong.

Rockford Fosgate Punch 6.5" spekers fit perfectly without any of the extra junk they said my vehicle "required" for installation and they're much deeper profile than most of the ones I looked at. I have 4" of depth to mount a speaker in the roll bar.

They sound a 100 times better and I'm installing my own head unit, amp and sub this weekend.

Stock Jeep speakers are simply awful.They distort at 1/2 volume and the magnets are tiny.
Even the expensive factory Infinity systems are below par with most aftermarket 200 watt head units and speakers available these days.
With the top down and doors off I need a good system to even hear the radio much less enjoy it.