lost transmission fluid line broke driving put back on.put 4 and a half in said full driving 1 to 2 miles recheck was empty no leak and nothing on stick should i replace tr filer

ty

The whole system probably holds 10 quarts so what you added filled the torque converter and you are still low as nothing is in the pan according to the dipstick reading. Okay. Fix that broken line, good time to drop the pan and replace filter if you have time, add 4 quarts and check after running through gears but don't drive it yet. Economical way to do this is buy two gallons to start. You may use it all and quarts are too expensive. Keep topping it up a pint at a time till it's good. A corroded/broken line seems common on the Blazer. Easy way to burn up transmission for people who don't watch fluid level or notice leaks on the ground.

should i change the tr filer

Filter change won't fix this problem but while putting in lots of new fluid, it would be the perfect time to drop the pan, wipe it out, and change the filter. It's easy and only $10 more.