I have been searching all over the web for this info. What I would like to do is convert a stereo track into 2 mono tracks where one mono track is the left side of the stereo track and the other one is the right side.
I want to do this because I want to see the difference in panning left and right with separate mono tracks. The stereo track only has one pan knob which I think is a balance knob and not a pan knob. I believe that this will make a lot of difference as far as panning goes.
 
Does anyone know how to do this in Sonar?

Unless you really want to process the sides or two mono tracks differently you don't have to do that. Use the Channel Tools plug in instead. It gives you that same functionality.

Select the track
From the Tracks menu in the Track view, select "Bounce to Tracks(s)"
In the "Bounce to Tracks" dialog
set "Source Category" to Tracks
set "Channel Format" to "Split Mono"

Channel Tools may be the preferred solution as Jeff suggests, but to answer the question, bounce the track and choose Split Mono under Channel Format.

Thanks everyone. I just got tired of looking at the reference manual trying to find it. Channel tools is easier, but once I have something in Sonar that I should be able to do I keep going until I can get it done. 
The whole thing is is that I think the pan pot on a stereo track is more of a balance pot and cannot work as a pan pot. The channel tools plugin is a great work around, but I would rather see a stereo track with 2 pan pots that I can use to put left and right where I want them without using extra plugins.

Essentially, the 2 main sliders on the Channel Tools plug act as separate Left/Right panning controls, so you won't gain anything from doing a split mono bounce other than the ability to apply different processing to the 2 channels

Bristol_Jonesey
Essentially, the 2 main sliders on the Channel Tools plug act as separate Left/Right panning controls, so you won't gain anything from doing a split mono bounce other than the ability to apply different processing to the 2 channels

If I used Channel Tools on the stereo track, You would be right. If I dont use channel tools, when I bounce the stereo track in split mono I have a pan pot on both mono tracks and wouldnt need the channel tools vst at all. If this could be done in Sonar getting 2 pan pots on the stereo tracks, for me this would be easier. This was a design choice by cakewalk to use a "balance pot"on stereo tracks instead of 2 pan pots.

I've used the Bounce > Split Mono technique when double-miking my guitar. The way my Mackie 402-VLZ3 mixer is set up, the first two channels can be linked together as a single stereo channel, so I take advantage of that to record with an AT-2020 and a Shure PG -48 (the Shure pointed at the sound hole, the AT pointed at the body/neck junction). Even though one is dynamic and the other a condenser, this works even though phantom power is either on for both channels or off for both channels on the Mackie. Apparently, a dynamic mike--if connected using a proper XLR cable--ignores the phantom power or it gets bled off to ground or some-such thing. Whatever; it works and doesn't destroy the mike which is all that matters to me.
 
Of course, this results in a stereo track in Sonar which I then Bounce > Split Mono.

It need not result in a stereo track Ron, just point your mics/interface inputs to 2 mono tracks yes?

It is the preferred method of most engineers to always use mono tracks, even when recording a stereo pair of mikes. It will always give you more control of your mix. 
About the only logical place for a stereo track is pre recorded music, a stereo effect processor or a stereo synth. But even those could be 2 mono tracks panned hard L/R. I'm struggling with this issue as my new Scarlett interface seems to revert to a stereo pair everytime I  insert a new audio track or try to re do an old track. I'll set it to 1 left mono, start recording and it's stereo?? and have to re set it again...One thing learned is Sonar hates changing interfaces mid session..