Rim size/offset

**lordfrosty** · 02-28-2009, 02:12 PM

Can someone please explain to me how you figure out rim size and about offsets negative/positve. I've got a 07 Sierra 1/2 ton with 275/55 20. So If I wanted to put 285/55 20 tires on what size rim would that be? And if i wanted my wheels to stick out a bit, how would I do that.

**adampaul1964** · 02-28-2009, 02:27 PM

the 285/55/20 is less than 1/2 inch taller than your current tire and only 3/8 of an inch wider, if you have factory rims the offset is positive 31mm so if you go to a rim with say 20 mm positive offset the tire would stick out around maybe 1/2 inch more at most, which doesn't seem like very much but visually it will make a big difference, hope this helps.

check this post out, it's pretty good:

http://www.gmtruckclub.com/forum/showthread.php?t=19213

**lordfrosty** · 02-28-2009, 04:47 PM

So, if I want to make my tires stick out more without changing my rims, how would I accomplish this.

**DrewsZ71** · 02-28-2009, 04:59 PM

Originally Posted by lordfrosty

Can someone please explain to me how you figure out rim size and about offsets negative/positve. I've got a 07 Sierra 1/2 ton with 275/55 20. So If I wanted to put 285/55 20 tires on what size rim would that be? And if i wanted my wheels to stick out a bit, how would I do that.

Here, try this website http://www.wheelsmaster.com/rt_specs...9&text1=&text2=

It lets you play around with different tire sizes and offsets and gives a pretty descriptive detail about what will and will not fit. The current setting on the page are from my truck but you can play around with them and get a good idea of what kind of clearances and measurements are going to look like.

**lordfrosty** · 03-01-2009, 01:37 AM

Thanks, thats a helpful website. So, the greater the offset the more the tire will stick out (is that correct). Is there something i can do to make my tires/rims stick out more without changing them.

**DrewsZ71** · 03-01-2009, 11:00 AM

The more the negative offset the more the tire/whell will stick out. Also, take this into account that the more the wheel/tire moves outward the closer it will bring it to hitting or rubbing on the fenders when the wheels are turned left or right.

**Chevy Newby** · 03-01-2009, 12:27 PM

I am having the same problem with my truck. I want to change my wheels but the wheels I want have a negative 25 offset which means they will stick out about 3 1/4", so I would need to do a body lift of maybe 3"s. But the greater the NEGATIVE offset of the wheel the further it will stick out, I do know that much. But maybe you can get away with adding spacers to your existing wheels and the wheel push them out a little bit and give you that aggresive truck look we are lookin for. Drew and Adam are 110% righyt in their statements...I love this site.

**94short&wide** · 05-25-2009, 10:32 PM

Originally Posted by lordfrosty

Can someone please explain to me how you figure out rim size and about offsets negative/positve. I've got a 07 Sierra 1/2 ton with 275/55 20. So If I wanted to put 285/55 20 tires on what size rim would that be? And if i wanted my wheels to stick out a bit, how would I do that.

my friend has a 55 chevy he is selling the rims will they fit my 94 gm 1500