What is min leveling lift needed to fit wheels

[bigceltic]

I have read through the various forums on wheel offset, backspacing, etc but was not able to find an answer to my specific question - if there is one I missed, please link to it, thanks.

My question is: I like the KMC Rockstar II wheels and always see the disclaimer: "Aggressive fitment. Vehicle should have lift kit or fender modifications for proper clearance." I think the 17" have a -12mm offset, and the 18" have 0mm offset and both have the same disclaimer. What is the min height leveling lift needed? I have seen them range from 1" to 3" (doing a quick Amazon search)? I assume that is dependent on the tire size as well (if I go with 17", tires will be stock size 265 70 17 and if 18" then 265 70 18 which is 1" taller but same width as stock according to https://tiresize.com/calculator/).

Thanks in advance,
George

 

[AEdelheit]

No lift as it does not increase tire clearance unless you go tall enough to drop the bump stops down, if anything get 1/2" longer high clearance control arms. Here is a good , accurate, write up on tire fitment https://www.thurenfabrication.com/tech/tire-and-wheel-fitment.html .

You really do not want a negative offset, it will decrease handling and increase component wear, 0 offset is still not ideal but better then negative.

 

[bigceltic]

Ok, I think it is making some sense to me after re-reading that page you sent. The Rockstar IIs come in a 20" with 18mm offset which seems to be better ("+18mm to +25mm wheels and stock arms, you will clear the arms full turn lock."). Cooper makes a Discoverer AT3 XLT in 285 55 R20 that using the size comparison site says it will be only 0.7" taller and 0.8" wider so it seems like it will work without a lift, and not change my speedo or performance much. The only downside is that size Cooper only has BSW - I am a white-lettering-out kinda guy. Now that I know what I am looking for, I will just have to find the right tires. Thanks again for the help.

George

 

[Ozymandias]

315/70-17 on stock rims is the biggest that only have a slight rub on the upper control arm at full lock.
285/75-17 should clear at all.

 

[AEdelheit]

Glad you got it figured out, it is really confusing and there is a lot of bad information out there.

 

[AH64ID]

The AT3 XLT’s are a great tire, so far at least, and id take a BSW to get that tire. I just put a set on and they are smooth, quiet, and fairly aggressive for an AT. Price is great too.

Severe Snow rated, designed for hauling, gravel roads, and a 60K mile warranty. I didn’t find anything else with similar specs.

 

[bigceltic]

Yeah, I have been watching the thread on best AT tires and I do like the Cooper AT3 XLT. I have been running the Cooper STT Pros for a while and have been happy and impressed with them.

If I do this, I need a spare, and I want to keep the 17" rim (or do you think it better to buy a steel/cheap 20"?) and so there are a number of 275 70 R17 tires that are super close in diameter to the 285 55 R20 Coopers. Would that work as a spare or is it better to get an exact same size? In my old Jeep Wrangler, I ran a 33" BFG AT but a same diameter but narrower spare.

 

[Ozymandias]

Driving on road go 20"
Driving off road stay 17"

 

[AH64ID]

Since it's a spare I'd get close, and cheap, as possible. A 4th gen 275/70R18 stock spare is slightly taller, but probably be the cheapest option.

 

[AH64ID]

Driving on road go 20"
Driving off road stay 17"

Or 18" for off road, as the 17" load ratings are fairly restrictive for many.

 

[Ozymandias]

Or 18" for off road, as the 17" load ratings are fairly restrictive for many.

Thats correct, but he asked for twenty or stock.

Would love to have 18" on my Rig buts either costly, wife says no no, or looks ugly.

 

[AH64ID]

Thats correct, but he asked for twenty or stock.

Would love to have 18" on my Rig buts either costly, wife says no no, or looks ugly.

Indeed!

The whole reason I went 19.5's several years ago was the cost vs load on 18's.... but now I own OE 18" wheels and in the stock size I was pleasantly surprised at tire prices...still TOO much, but not as bad as other sizes or brands.

 

[bigceltic]

I would say I do 90%-95% on road - with very little off road (forest service roads, not major 4 wheelin) when we are at national parks and such. I will check craigslist and ebay for 4th gen tires. Thanks for the suggestion.