I have been itching to upgrade my stock 17" to 18" wheels on my '04 Fx4 Screw, but I've been getting mixed opinions from the local naysayers, so I figured I would come here and ask the experts. I tried doing a search but didn't really find anything specific, as I am a semi n00b when it comes to rims and tires.

As stated, I want to upgrade to 18" wheels from my stock 17's and am looking at these:




As my truck is black, and I think these would just look brutal. So the questions I'm concerned about are:

Are the lug patterns the same from 17's to 18's?

I'll do a little more research here on the forums about tire size, but I have the stock Generals on there now and would like to upgrade to BFGoodrich All Terrain T/A KO's. With the slight change in rim size, how much of an effect will this have on my speedometer? Would a programmer be enough to compensate?

How much stress, if any, would this put on my rearend?

Being that I live 20 miles from downtown Chicago, I have to deal with snow and alot of road salt in the winter. I've read that polished aluminum is NOT the way to go for these weather conditions, unless I plan on hosing my rims off every day. Would just hte plain aluminum wheel be ok with moderate upkeep in the winter?

Eventually, I will have a 6" lift added, but will probably just go with a Top Gunz leveling kit to get me going.

OH YEA! Ok, now I feel really kind of stupid, but is there anywhere to find out exactly what it means when it speaks of "offsets" and "backspace"? I had an idea what I thought it meant and have a feeling I'm WAY off.

Any help would be appreciated. I'll keep searching the forums when I get home tonight and see if I missed a post about exactly what I'm asking.

Thanks guys.

 

Ok, I got some info on the size difference but now I'm concerned with the backspacing and the offset. I found a cool site that had a great diagram defining the 2.

I don't plan on doing hardcore offroading, but I do like getting my truck dirty.

Pretty much any size of rim I get in 18" has a 4.5" backspacing.

As far as the offset, most are -12mm, but one has a +30mm offset. Are these measurments the distance from dead center of the rim towards the front of the rim area where the mounting holes are? I hope that doesn't sound too rediculous, but I don't know how else to describe it, haha. Meaning, the lower the measurement, possibly, the stronger the rim, due to the actual mounting surface being closer to dead center?

Be honest, if I'm completely wrong, please let me know. =D

 

Lug patterns must be the same. On BS, just search for "backspace, measure" and there will be several good threads. Offset is a bit trickier and is not as easy to measure as backspacing, so don't worry about that.