beardofZeus123

Hey guys i'm new to this and seeking some help on getting new wheels and tires for my truck. I recently got a 2007 chevy silverado, crew cab. In the future I was wanting to get aftermarket wheels and tires for it. I have been looking at some 20x10 wheels and 33" tires (305-55-20). I was wondering with that combination of wheel and tire what is the minimal lift I could put on the truck without rubbing. I don't know a lot about all of this any help would be appreciated!!

SWHouston

Need a little more info...
On the sticker on the Drivers Door,
what size tire is listed as original equipment ?

beardofZeus123

well the inside of the door says 265/70/17..but the dealer put 265/65/18 bridgeston tires on 18 inch chevy wheels

SWHouston

That's ok, I just needed the basic size of one of the OEM's. The 18's were probably an optional for your ride.

Here's what I see...
You'll be increasing the overall diameter of the Tire by about 2.0". The 305's are actually about 33.5". That's not excessive, and if any problems arise, it shouldn't be from that. That will however cause a Speedometer error, making your actual speed faster than the reading. Most times one can re-program the Computer, to make that correction. If not, you'll just have to deal with it. There may be mildly noticeable changes in the perceived breaking ability and power of your vehicle as well.

Now, here's where you need to be careful...
You'll be increasing the width of the Tread about the same (2") which will move/widen the inside of the Tire, 1" closer to your framework and fender-wells. Most times, that's not excessive, but it may just be close enough to rub.

You said "Aftermarket" on the Rims, and 10" width is ok for the 305's. Now if you had selected a GM Rim, which was an option for your specific vehicle, GM would have "offset/moved" the Rim outward, to allow for the additional Tire Width.

Now, here's where you have to "trust" the Rim manufacturer...
If you specify "exactly" what vehicle you're putting the Rims on, and the Dealer says they WILL work, that should mean that they have made any corrective adjustments to consider rubbing, and it's their guarantee that won't happen.

A satisfaction guarantee and no hassle return policy may be needed.

However, IF there is only a very slight rub in a place, there are things you can do to eliminate that, but it can't be excessive. We can discuss that if needed at some point.

Good Luck !

PS:
The issue of concern here is called "offset", you can read more about that, at...
http://www.tirerack.com/wheels/tech/...jsp?techid=101