Drain still clogged after being snaked.

Here's what I've been dealing with so far.

A while back my washing machine would start making a glugging noise and back up during the drain cycle. I figured it was due to washing large loads of laundry. I adjusted the loads and it happened rarely. Recently thought I have noticed that the washing machine drain and the downstairs toilet next to the washer would both start making the glugging sound before the washing machine drain would back up. Sometimes the downstairs toilet would back up also. Now it has gotten to the point that I don't have to run the washer for the toilet to glug or backup. Guess it just depends on the day, IDK. But lately when the upstairs toilet would flush or the shower is being run it might either make the downstairs toilet glugg for a minute then back it up or it will be fine.

I got tired of this and rented a 100 ft drain snake from home depot and ran it though the drain of the downstairs toilet. On the first run with the spade snake bit I noticed small roots tangled on the cable. So I ran the root cleaning bit and the C bit though the drains. After that everything seemed to work normally.

I did this on Sunday Oct 4th. and toilet is backing up again Oct 8-9.

I really don't know what else to do after running a snake though the drain. I really don't have the funds for a plumber right now.

I have not yet tried to check or clean out the vents on the roof, I don't have a ladder to get to the roof. But would clogged roof vents cause this kind of problem? Or could it be something else?

Any help, suggestions or tips would be appreciated.

Stay off the roof.

Have a professional come and do a camera inspection of the line. If you have roots, you likely have a dip in the drainage as well, or even more roots. The camera will show you what's going on.

Thank you for your kind and professional input. Forgive my ignorance, but could you explain what a dip in the drainage problem is and how bad is it? to fix.

maybe 100 ft wasn't enough.
If it's longer than 100 ft there should be a clean out.
possible the root ball fell off the pipe as you pulled it out.
Run plenety of water while cleaning the line .
I have seen old lines that had a lot of build up.
after snaking it that debri lies on bottom of drain like sand and causes problems.

snake it again

I tried to run water down the drain as I snaked it the first time, but it might not have been enough water. I know the tree's I have are big and old. So it wouldn't doubt I missed one, or I hit a root and thought I was at the end of the pipe.
Funny thing about the clean out port. My neighbor told me the houses that are in my neighborhood are so old that they don't have a clean out. He had to dig up the line and put one in. He also told me he had to clean out a cast iron trap that was full of crud and gunk. So I guess I've got a bit of digging so a clean out port can be installed. It also wouldn't surprise me if sand is getting into the line. The soil here in Savannah is pretty much all sand.

Agree with the camera inspection and locate the issue

Also there is no end of the pipe unless you are on septic.. If on city you probably didn't reach the stopage

Call the city and see if they can camera their line up to yours. Buy root-x at your local hardware store. Do the root-x at night and in the morning flush everything good.