I have an LG top loading washer, model WT4870CW. During the wash cycle the machine makes a grinding noise. The noise does not occur during draining and spin cycles. Any idea what could be the issue?

Probably motor control board is bad

This sounds like you have a problem with the tub suspension rods (4 of them) if one is faulty, you will have to replace all four of them to cure the problem.
It could be that they just need to be realigned as the grinding sound is the inner tub contacting the outer tub housing.

How To Fix A Washing Machine Making Noise During The ...

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Jul 27, 2015 - Agitator directional cogs aka "agitator dogs" (top load washers) ... If you hear a rubbing sound or the drum spins uneven, then the ... A washer making a loud noise during spin cycle can also be caused ... The clutch in a washing machine connects the inner wash tub to the ..... May 8, 2015; High Water Bill?

Dishwasher Making Loud Grinding Noise During Wash Cycle

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Apr 11, 2014 - Dishwasher Making Loud Grinding Noise During Wash Cycle ... GE, Whirlpool, Frigidaire, KitchenAid, Maytag, Kenmore, and LG) this is a .... Our Amana dishwasher is making a loud, high-pitched squealing noise throughout the wash ....Out Of A Washing Machine - Top Load & Front Load September 30, ...

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check back of unit as the concrete on the back may of been dislodged check not over loaded also the belt maybe loose or streached

Can I have the hole model number?

http://www.applianceaid.com/neptune8.html

Most noises from a washing machine occur during the spin cycle. If you hear loud thumping during the spin, the load of clothes may have become unbalanced. Stop the washer and redistribute the clothes, then re-start it. Repeat these steps if necessary.

bad clutch or no belt

Most noises from a washing machine occur during the spin cycle. If you hear loud thumping during the spin, the load of clothes may have become unbalanced. Stop the washer and redistribute the clothes, then re-start it. Repeat these steps if necessary.

The inside of your agitator became worn, and possible strip out the spline that allows the agitator to properly grip the shaft. The loud noise mustly occurs during the spin cycle. If you hear this loud noise your load of clothes may have become unbalanced. Stop the washer and redistribute the clothes, then re-start it.