It is October and I need to travel in an RV, towing a small car, from Salt Lake City to Denver. I'm concerned about road conditions at this time of the year and don't want to get caught in snow. Is it better to go I-80 through Wyoming and then down into Denver? Or, is it better to go south from SLC and the east on I-70. I'm not too concerned about time as I have several days to do it in, but I'm concerned about road conditions, rest areas appropriate for RVs and not wanting snow. I'm a single woman traveling solo.
Both ways would probably be fine during October. Major snowfall can happen in October, but it's rare for it to close the highway for long. Your entire drive will be around 12 hours (I'm adding plenty of extra time since you're in an RV towing a car and you'll be driving alone).
You say that you have a few days to do this trip in, so I would just decide which way you're going as close to the departure time as possible. That way, you can watch the weather, and decide on a different route if snow is expected on one of the highways.
Assuming the weather is fine, I'd probably choose to take 80 because it's interstate freeway the entire time, which I'd feel more comfortable with (since I'm not usually driving an RV or towing a car).