Why does my suburban engine stop while driving

Is the check engine light on ?
It could be a faulty speed sensor on the transmission.

The engine is overheating, check the anti-freeze level when cold, refill and repair the leaks. Check belts that drive the water pump.

I am assuming the fan clutch stops spinning when the engine stops.
Could it be something leaking vac ?

Sounds like warped rotors that are siezing up due to your calipers sticking.

it may be your shift solenoids their are two of them that controls upshift #1 solenoid controls 1-2 gears then #2 controls 3-4 which transmission do you have in your suburban do you have the 4L60E OR 4L80E if you have an older suburban with a Carb on it then you will have the 700rr

replace the sending unit if the pressure was low the engine would be noisey

I suspect you have had an oil pump failure. To get at the rotory gear oil pump you will have to drop the oil pan. After you take the pan off, ( having drained the oil the oil pump is what the oil pick up line leads into. That pick up assy. is a round shaped disc with a screen inside it. Clean the screen first then the oil pump. Install new oil pan gasket on reassembly. Hope that helps you. Please let me know.

Hopefully the engine was not damaged when the pump broke. If it was you may need a complete engine rebuild, MAYBE.

Stop engine and ck for a loose pully, Check the belt tensioner. flying parts under the hood no good.

check bearings

the idle speed is computer controlled and not adjustable, slow idle is caused by a dirty intake, do the following.

Here are some of the causes of surges, stalls at stops, slow idle speed, erratic idle speed, rough idle and engine hesitation (and other problems), it is in most cases the idle speed control air-bypass valve and or throttle valve and upper intake, these area's get full of gunk and combustion residue over the miles and cause idle issues (stalls, low idle) like yours, Get a can of intake cleaner from any local parts store, not carb spray, intake cleaner, it is made by a company called CRC, remove the air intake hose to the engine, hold the idle high so the engine won't stall, then spray the can of cleaner into the intake while keeping the engine running, use at least 1/2 the can, shut down the engine and disconnect the battery for 5 minutes, then restart and complete a number of mixed driving cycles, town, freeway, stop and go etc., after a few days the problem will go away as the system will relearn to the clean intake.