I use Dodo Juice Supernatural Leather Cleaner on any thing leather on my cars and really love the product. And like @Bishop187 has mentioned use a soft toothbrush on the steering wheel on regular basis.
I don't think using a normal upholstery cleaner would be a good idea as dedicated leather cleaner are usually water based and have blend of soap and mild solvents compared to slightly harsher for upholstery.
A few pics of leather cleaned (including steering wheel) with Dodo Juice.
View attachment 201755
Yes. Totally forgot about Dodo Juice Supernatural Leather Cleaner. It’s amazing.
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