Got 4 toilets in the house (3 upstairs), We're having issues with two upstairs, but one more than one.
The toilet that is giving most of the problems have been over flowing on a regular. Whenever it clogs, if it's plunged slightly, it flushes fine. But when it's flushed repeatedly it goes down then comes back up then flushes again. Sometimes the bowl fills up then starts going down slowly before it flushes and gurgles.
I tried liquid Rotor Rooter, no help.

Has this been going on for a while? It may be a vent clogged or no vent or vent to far away form the toilet.

Can you see a pipe close to any 2nd floor toilet coming out of the roof?

If you fill the sinks up in those bathrooms and pull the plug how well does that drain?

A "gurgle" tell you the system's attempting to vent through the toilet. The "gurgle" you hear is air being pulled through the toilets trap. This indicated a blocked vent.
The solution would be to rent a sewer snake,(see image) and snake the lavatory roof vent. Put out enough snake to reach the base and 16 feet more, good luck, Tom

Thanks gents.
21boat:
The pipe I see by the toilet is the shut off. This has been ongoing for some months now on and off, but is has progressively gotten worst, since the post it has a very slow drain now after plunging.
And the answer to your last question, all the sinks in the bathroom drain good.

speedball1:
I was thinking of trying the snake from the toilet, would that work instead of the roof?

speedball1:I was thinking of trying the snake from the toilet, would that work instead of the roof?
Not in this case. As I stated;
A "gurgle" tell you the system's attempting to vent through the toilet. The "gurgle" you hear is air being pulled through the toilets trap. This indicated a blocked vent.
The only way to clear a blocked vent is through the bathroom roof vent.
Looks like you'll be doing some climbing. Good luck and be careful up there. Tom