I have a 1992 corolla brake peddal pulsalating?

Replacing the rotors is usually a good idea if you experience shimmying when braking. It is recommend that you replace both the rotor and the brake pads at the same time. The reference for this information is from this site:

https://practicalmechanic.com/2017/10/25/how-to-change-brake-rotors-on-a-toyota-corolla/

1. Jack up the vehicle and put some jack stands under it.
2. Remove the Lug nuts and the tire.
3. Carefully remove the caliper and caliper bracket.
4. Remove the old rotor. And replace it with the new rotor.
5. Reassemble the caliper bracket
6. Put on the new brakes pads and reassemble the caliper.
7. Put the tire and lug nuts back on.
8. Be sure to use the proper torque specifications.
9. Remove the jack stands and lower the vehicle.
10. Read torque the lug nuts to the proper specification.
11. Follow the link for details and photos.

https://practicalmechanic.com/2017/10/25/how-to-change-brake-rotors-on-a-toyota-corolla/

You need to compress the calipar, sounds like a groove in the rotor, a big screw driver works

need to check (rotors or brake disc for specific, thinkess) then replace brake pads .no need to add brake fluid.

jack up frt end. remove wheels. take note of how the brakes go together. do 1 side at a time so you can use the other side as a referance. remove caliper bolts. use a c-clamp to push in caliper pistons. remove old pads. than remove caliper bracket and rotors.dont be afraid its not a big deal. make sure to check brake fluid level and pump the pedal when the job is completed.

You need to replace the front pads and resurface or replace the rotors. Also check your slides for the calipers and make sure they are clean and well lubed when yo reassemble the brakes. If the slight pull still occurs either nthe flex hose or caliper is starting to get weak. But I think for now doing the front pads and rotors will solve your problems.

http://car-and-truck-repair.casubi.com/article/487317/basic-car-maintainence-ii-brake-pad-change
Plz visit this site,
Hope this helps!

30% of a brake pad is still quiet a fair bit, unless you drive and use performance pads.

dealerships do say alot to make money from there customers,

if you stick to speed limits or a little bit over with no harsh braking and down gearing for cornering you will be fine with the 30% left on the pads, get them sorted when you come back though or after a week or so of being back :)

Even though there may be some brake pad remaining, sometimes you need to machine or replace the rotors in order to get rid of a noise. Rotors can develop a bad wear pattern that acts against a glazed pad to produce a loud noise even if they are not worn out. Replace the front brakes, pads and rotors.

The brake hose maybe bad replace it. They can claps on then self inside the hose. One work to check is have someone push the brake paddle down and release it if the rotor is hard to turn, open the bleeder vale if fluid comes out and the rotor turns freely that you problem.