Will pretreating remove ground in dirt? If so what product should I use?
Answer: Sounds like you need a good deep cleaning! In order to get these ground-in dirt stains, I recommend trying Tough Stain Pre-Treat for Carpet and Upholstery. This product will loosen the engrained dirt. After using this product properly (you will find the instructions on the back of the bottle) use a portable or upright deep cleaner to flush out the extra dirt.
If there is any discoloration remaining, follow up with OxyPro® Stain Remover for Carpet .