The tire appeared to have a slow leak as I kept having to add air to it. So, I used Fix a Flat and now I have vibration at high speeds from that tire. What do you think might be the problem.
I have also been told that my rear axle might need to be replaced.
Please help. Not sure what to do and have little $$ to do anything.
It's definitely related to using Fix-A-Flat. The Fix-A-Flat has added enough weight to the inside of the tire to throw off balance.
Unfortunately, the fluid it puts inside the tire will likely continue to keep that tire unbalanced, even if it is rebalanced at a shop. They may even find they are unable to balance it because when it's on the machine, since the weight inside (the liquid) keeps moving around, it will be impossible to "zero" the weight of the tire and achieve a smooth ride. The good news is that you likely do NOT need an axle replacement - the unbalanced tire won't cause that to fail.
The proper solution here is to either have the tire professionally patched (which would include also unmounting the tire from the rim and cleaning out the Fix-A-Flat "gunk"), or replacing the tire. Fix-A-Flat isn't intended to be a permanent fix for a leaking tire.
I suspect that the fix-a-flat has thrown your wheel out of balance.
Most tyre fitters will balance your wheels for a very small cost. I would have this done first before spending any more time or money looking at the axle, etc...
