I picked up a 01 996 and the guy never cleaned the inside of the rims and now I'm trying to get them cleaned. I used the regular washing soap and that took care of some of the dirt but what remains almost looks like stains. Any suggestions on removing that?

I used Chemical Guys iron remover, let it soak as directed, scrubbed the barrels, then used Meguairs All Wheel Cleaner. Repeated until the desired results are achieved.

For the wheel face I use the same Meguiar's Gold Class I use on the whole car and for the inner barrels, I use this.

I had stains on my Subaru outback wheels. Guy at O'Reilly's told me to use oven cleaner. Worked pretty well.

Follow up question. What are you using to remove old tire weight adhesive?

for cleaning I like P21-S wheel cleaner. It works great and doesn’t stink like a lot of the others.

Highly recommend you take the wheels off the car, and after cleaning thoroughly put a good coat of hard wax/sealer to help keep them clean.

3m adhesive remover

I've heard this stuff is amazing (pun not avoidable) for all kinds of stuff, but keep forgetting to pick up a bottle. Just placed an order on Amazon.

I’d probably start with an iron remover but I use these two together:

https://a.co/d/g9SjWoH

and

https://a.co/d/haE1zhP

The one thing about Iron remover is to make sure you get all of it off. Usually use a separate bottle or pump sprayer. I use P&S for their Bead Maker as well, for best results remove the wheel and work off the car as some of advised.