problem with my truck

i have a 2001 dodge ram 1500. i just replaced the radiator yesterday, and i have a misfire in the first and, 6th cylinder. i drove it a total of 30-50 minutes yesterday after the radiator was replaced. as i parked for the night i reversed in and i noticed that there was white smoke coming from the exhaust. i decided to let it rest till morning.
i fired it up this morning and it seemed ok drove it to autozone and it engine light red misfire in cylinder 1 & 6 nothing else
i drove it home and the heat gauge whet high not redline, not even the last white line but pretty high. no white smoke came out untill i put it in reverse.
the smoke smelt like burning gas

the work that has been done to the truck is:
new engine
new spark plugs wires and coils
new oil pump
new thermostat
new fuel pump
new radiator
new tires

the a/c and heat don't work but the last week i have left the knob on the max heat, not sure if it is a contributing factor but im giving all the info i can

please let me know what you think

Have you checked to see if the cooling system may be airlocked? How about the water pump, it is working correctly ? The heater core? What's it's condition ? Usage of the wrong coolant or mixing of incorrect fluid types such as coolant can lead to build ups of a sludge type issue in cooling systems and blockages of passages including heater cores. Not limited to just those parts but the entire system
Usage of stop leak for coolant leaks also clogs heater cores as well. I would dig a bit deeper w the no heat issue.....

Misfiring sounds like it's in a " Limp Mode" and a repetitive issue.... computers do that to prevent the engine being damaged from issues of detonation, improper ignition timing , a crank or cam sensor that' s bad or both. Try a live data scan and if it happens again you might be able to see what the little gremlin is and where too.

The white smoke is burning coolant n gas. I have a feeling either a head gasket, intake gasket or both. Have you checked the oil and the coolant levels ? Check your fluid levels and what they look like . Milky oil is water/ coolant in oil, white smoke = burning coolant. You have either a head gasket leaking or intake leaking and going out the tail pipe. That will foul plugs and cause a miss this case it sounds like the engine is shutting down the affected cylinders 1 & 6 ....maybe a cracked head too. Check the plugs wet plug =water in cylinder= cracked head check w a light to see on #1 if not bump the engine if it blows coolant w the plug out ....cracked head . Saw this before on a 5.9 360 Ram 2500 at work . The heads were shot and cracked ....literally a cooked motor. However it doesn't explain it only happening in Reverse. Those senarios are constant engine not transmission

i have a 2001 dodge ram 1500. i just replaced the radiator yesterday, and i have a misfire in the first and, 6th cylinder. i drove it a total of 30-50 minutes yesterday after the radiator was replaced. as i parked for the night i reversed in and i noticed that there was white smoke coming from the exhaust. i decided to let it rest till morning.
i fired it up this morning and it seemed ok drove it to autozone and it engine light red misfire in cylinder 1 & 6 nothing else
i drove it home and the heat gauge whet high not redline, not even the last white line but pretty high. no white smoke came out untill i put it in reverse.
the smoke smelt like burning gas

the work that has been done to the truck is:
new engine
new spark plugs wires and coils
new oil pump
new thermostat
new fuel pump
new radiator
new tires

the a/c and heat don't work but the last week i have left the knob on the max heat, not sure if it is a contributing factor but im giving all the info i can

please let me know what you think
Go to Advanced Auto or Auto Zone get a loaner pressure tester Put about about 12 to 14 psi on the tester gauge. Start the engine if the gauge pulsates you have a blown head gasket or a crack. Rebuilt engines sometimes have problems and this should be under warranty. Napa sells sells a test kit for checking combustion in the anti freeze.
An oil analysis will check for anti freeze in the oil.
If you have air in the cooling system Put a floor jack under it and raise front end this sometimes helps to get rid of air in the cooling system.

What did you find out that was wrong with the truck?

My vote would also be to check for blown head gasket. Couple tablespoons of paprika into the rad :D