They will fit in the wheel well. Probably gonna rub on turns though. A 2-2.5 inch lift should help that.

 

so leveling kit would fix that

 

Would definitely help

 

I put a 2" leveling kit my 04 and installed 285 70 17's. They rub slightly when I make a hard turn so I think the 305's would most likely rub

 

They may fit if you put a leveling kit and a 1.5" body lift on. Don't know how high you'd want to go or what you want to pay but that's the cheapest route. I've got 285s with a leveling kit and rear leafs from a 2500 and i rub just a little at full lock.

 

Are you putting them on stock or aftermarket wheels? The more negative offset the wheel(more it sticks out of the fender) the more chance of rubbing. Id suggest a leveling kit or atleast some turns up on the torsion keys though. Some trimming of lower corner of bumper probably needed as well.

 

my back spacing on my rims 5 1/4 and i am doing a full leveling kit

 

Should fit but may have a little trimming. Will look good though

 

I had 285/75/16 on my stock height 04 silverado and although they were close they never rubbed . The 305/70/16 has the same diamter at 32.8 inches so you will probably be fine, the extra 20mm in width may rub in turns though.

 

When I had my 99 nbs I leveled it with the stock keys and had 285-75-16s and had no rubbing. They filled the wheel wells nicely too.

 

What wheels would these be going on? I think a stock 16" rim is only 7" wide. That's definitely too narrow for a 305.
IIRC, a 9" wide rim is the minimum recommended for 305s.

 

my new rims are 10 inches wide