: How can my 2 subdomains create more value for each other? I have a domain example.com that has 2 entities www.example.com This is my product's website. It has great content and is updated periodically

I have a domain example.com that has 2 entities
example.com
This is my product's website. It has great content and is updated periodically by additions to the blog.

Sessions per day: 150
Indexed pages: 238
Links to the site: 347

The links are generally pretty good quality. There are a few sites where I'm not sure what they are.

support.example.com

This is actually a web application that provides information that's stored in a database. There's good content that surrounds the info from the database. Things are set up so that the pages will be found for very specific queries (e.g. "How do I change the oil filter on a 1987 Ford Mustang").

The information in this app is translated into 34 languages. Because of that, and all of the combinations of data coming from the database, the site theoretically has 723K pages. I also build the URLs so they look like you're accessing an HTML page and are very readable.

Sessions per day: 1700 (just about all from searches)
Indexed pages: 575K
Links to the site: negligible

All of the support pages have links back to the www site.

So what's the question?

Well, I checked my PageRank and saw that it was 0 and became concerned. I started to look at all of the metrics on the sites and try to understand this. However, on further review I see that newer websites will always have a 0 PageRank (or at least that's what gets reported).

So the question is broader: is what I'm doing reasonable? I'm a bit concerned about the links from support to Because there's so many of them, is it possible that Google will see this as an attempt to game the system?

The support site is also currently ad free. If I start serving AdSense ads, will Google give it a little push to attract more visitors?

In general, is there anything else I can do to have these 2 sites create more value for each other?