Model FTF530ES1 - when on the spin cycle the grinding noise is loud...what could it be?

SOURCE: Frigidaire Washing Machine Model # GLTF1670AS0 Makes very loud

If you want to take the time, I just replaced my drum bearings and seal for $62.00. No really any special tools needed. My model showed the bearings were not sold seperately and you had to buy the complete tub half, but when you take it apart, you can knock out the bearings and buy them online or at a bearing house. I have a seal part number also.
If I remember right the bearing part numbers are 6306-2RS and 6307-2RS (1 each) and the seal is a 40mmX80mmX10mm thick. Make sure you get the -2RS bearings because they are sealed. The ones that came out of mine are shielded bearings ( -Z ) and they will not resist moisture if the seal shaft seal fails.
Most AutoZones have seal and bearing drivers you can "borrow". They really help during installation so you don't deform the seal or damage the new bearings.

Any good bearing house should be able to macth on up or if you post back I can give you the exact number. I think most brands of front washer use the same bearings, but you may want to take yours apart before you buy.
Worst case the junk yard doesn't care if it comes in pieces or as one piece. Give it a try.

Not sure you will want to get this involved, but its not really too bad of a job.

SOURCE: LOUD BANGING AND SCRATCHING NOISE ON SPIN CYCLE

Urgent stop using it !!!!

The drum suspension is coming to bits , get someone in to look at it before the drum comes through the side of the machine

SOURCE: My model #gltr1670aso makes loud noises during spin cycle

Usually this is due to either the drum support breaking or the back bearing being bad-neither easy to fix- or worth it. Try lifting the drum up and down, if it moves up and down they are bad. I see this a lot, and the price of repair isn't worth it. Craig

SOURCE: LOUD CLANGING EXCEESIVE NOISE DURING SPIN CYCLE.

i would think the bearing

SOURCE: Frigidaire was tub makes loud thump noise during spin cycle....

Need more information to make an accurate diagnosis, try removing the front panel (two screws at bottom) and visually check first the belt (all the way around) and then the springs that hold the tub suspended.
I would bet on the belt.
Quentin