has it always been this slow? perhaps the belt is slipping thus not move very fast. Is the engine running full speed? obviously the mower moves proportionatly to the engine speed.
If everything is ok, u could replace the pulley on the engine shaft with a bigger pulley. You would need to do some math to calculate how fast u want it to go thus what size pulley. Also, u would need to get a bigger belt.

U can calculate the new belt length @ http://www.durabelt.com/beltlengthcalculator.php (method 3)

I think its always been slow, but it does seem to be slower then when i first purchased it. Im considering taking a look at the gearing on it, but im preety sure the engine is speed is as high as it was when i purchased it. a clean and lube would probably solve the problem, but im more concerned about if pushing it myself will damage it as i dont really mind getting the exercise, its a matter of breaking it or not.

I assume this is a front wheel propelled mower. If it is, I had one and hated it. It should be fine pushing it because it is made to have a "neutral" rolling option. However, they are a real bear to push...awful actually. I would personally remove as many of the self propelled parts as you can and use it as a free wheel push mower.

The belts on the craftsman front drive do tend to stretch over time. Have multiple personal experiences with belt changes making a noticable diff in speed. I am not questioning your memory, but over 5 years it could become progressively slower without noticing.

That's the difference between a front wheel drive and a rear wheel drive mower. the rear wheel drive costs a few dollars more but seldom needs to be pushed even uphill unless one of the driving wheels gets caught in a chuckhole.

I will say that it drives itself quite nicely, you dont have to push it when your rounding a corner, it keeps itself rolling. Anyway thanks for the feeback guys, i think ill do some maintenance on it and consider getting a new belt or just stripping some of the mechanics so the wheels roll on there own.

I've had 4 self propelled mowers. The first 3 (2 Craftsman & 1 Husqvarna) all had the same lame system where the mower (supposedly) moves itself when you squeeze a handle positioned in front of the bar @ the top of the mower's push handle. This is a belt drive system. I returned all of these mowers very shortly after purchase for failure to "self propel" in tall or wet grass.

I understand that mowing is not recommended in tall (I'm talking about 4.5") or wet grass. However, I don't have time to mow 2x/wk.

I got fed up with the aforementioned drive system & spent just a little more $ on a Honda HRR216VXA with the Smart Drive Variable Speed system. It is a true work horse (compared to Craftsman & Husky) in tall or wet grass. It plows through where the crappy belt drive system of Craftsman & Husky just quit.

By the way, the mulching is also very good with this mower, & the other features you get with it are WAY worth the money compared to Craftsman & Husky.