Hello I could use some input. I have a 20/20 GX it came with the stock rims which are 7.5" wide,18 in with an offset of 25. I pick up a spare set from a Tacoma which are 17 inch with an offset of 30, which from my understanding would put the rim approximately a quarter inch deeper into the wheel well. I am looking for the maximum size tire that I can put in here with no modifications other than possibly heat bending the liner a little. I want full articulation without rubbing to take this off road. Any suggestions would be greatly appreciated

 

Combining larger tires with wheels that have even more positive offset than stock will really screw up the handling/steering in a bad way. Google "scrub radius". Larger diameter tires will drive better with slightly less offset wheels (more negative, or less positive). This moves the tire-to-road contact patch more outboard, and better in-line with the axis of rotation as defined by the upper and lower ball joints.

 

does that apply if it is only a 5 mm toward the inboard?

 

... IMHO the standard issue Lexus / Toyota wheels on every body-on-frame vehicle has either 7.0" or 7.5" width, combined with a positive offset that is way too inboard ... for that lovely soccer mom stance.

For me, an 8.5" wheel (to reduce sidewall bulge) with a 0 offset (25mm outboard from stock) puts the edge of the tire in perfect vertical alignment with the edge of the fender flare ... not at all aggressive ... just looks more planted, with the wider track slightly improving handling in the twisties.

Also when I have dumped 18's for 17's ... I always went with an LT E1 tire for a stiffer sidewall. From a looks standpoint ... for that "offroad look" the general rule of thumb is a minimum 2:1 ratio ... tire diameter to wheel diameter ... which is why many off-roaders consider running 20's or 22's as "pimpish" ... sorry, just reporting ... no insult intended on my part ...

 

thanks I will keep that in mind for sure. So I have a choice to make get rid of these 30 mm offset rims or put a 1-in spacer. Seems to me that would be the same outcome as long as you're in the group of people who have no concerns with spacers. there seems to be two different camps one said it's okay one says they're Dead set against wheel spacers. Obviously the safer thing would be to buy rims with the proper offset but since I already made the mistake of purchasing these beautiful extra set of 17 inch rims I'm not sure if I want to do that, and I think I would only do that if I could first sell this set of rims. So I will have to give each of these ideas some thought. Thanks for your input. I may follow half of it sticking with the seven and a half inch rim bought with a closer to zero offset

 

... as stated in earlier posts, quality spacers are fine ... but should not be a "install and forget" ... torque should be religiously checked with every 6,000 mile tire rotation / balance ... with any brake work being performed by an OCD technician who understands spacers.

 

I did Google SCRUB Radius and it was a little confusing to follow along but the one site seem to say pushing your tires out,in the front especially cause your tires to wear quickly for some reason. I didn't quite follow the reasoning, I'm guessing your tire tread will is on a slight tilt and you would be wearing either inner or the outer edge. I'm assuming it would be the inner Edge. But like I said it was pretty confusing. It also said that by pushing the tires out if one of the tires were to go through a puddle and start to hydroplane while the other wasn't hydroplaning the car would be unnormaly forced toward the tire with grip. But it did say not to push them out, that closer to a zero offset is ideal. That's what I took away from my search

 

I seem to recall reading the one person's input on wheel spacers is not only a safety Factor but his point was using a spacer to push your Rim out changes the angle of the arc as the wheel turns versus having a proper offset it wouldn't have that exaggerated Arc....OR possibly I am recalling that improperly and he may have said either way whether it's a wheel spacer or an offset change toward pushing the wheel outward causes the wheel Arc to change and possibly cause Tire rub during a turn. I think that's maybe what it was

 

... all spacers do is change the wheel offset ... so an ET = 0 wheel (zero offset) would be the same as an ET +25 wheel (25mm inboard offset) with a 25mm spacer ... absolutely no difference ... other than the safety consideration of running spacers.

 

the question I have about spacers comes along due to a comment by another poster here. And their comment said that pushing the tire out from the wheel wells original position adds torque on the bearings. I'm trying to picture if the torque on the bearings is any different with a spacer as compared to switching to a different Rim that has the equivalent amount of offset as that spacer makes. What are everybody's thoughts here

 

No difference ...

 

Sorry if I'm beating a dead horse here,. But just to clarify- pushing your wheels out farther than stock does put excess strain on your bearings?. If So both methods hurt the bearings, using a wheel spacer to push your wheel further out versus using a rim that has a lower offset which obtains the same wheel position in the wheel well,both straining your bearings correct?.thots please.

 

Lexus / Toyota 4-Wheel Drive Body-on-Frame vehicles are designed to go offroad ... imposing way more load and impacts to the bearings than the 95% that never go off-pavement. Yes, the bearings will see an increase in load when pushing the wheel offset more outboard ... but anything that does not go negative on the offset will be a rounding error in the scheme of consideration ... Toyota overengineers everything ... and there are too many that run wheels in this range on the 4-Runner, Tacoma, FJ Cruiser and Lexus GX forums that have not flagged any measurable reduction in bearing life.

 

"but anything that does not go negative on the offset will be a rounding error in the scheme of consideration".... can you please explain this part of your reply. Other than that I think what you're saying is that these bearings take a hell of a beating when they go off road so it's not really something I should be concerned with for the most part because I am not a heavy duty off-roader or rock crawler where the bearings must really really be placed under a tremendous load, and apparently still survive!. But I don't understand that one sentence. Thanks for your input it sounds very intelligent/spot on.... I think that part of your sentence is basically saying go negative because it would be an error not to go negative when you consider all the advantages of doing so

 

Another reason to go with the larger wheels is you have more option with big brake kits. If you have 17s, you are limited to 338mm rotors and 6 pistoncalipers (eg, Stoptech ST60). With 18s, you can fit 355mm 2 piece rotors w/ 6 piston calipers. I have the latter setup on my LX470 w/ OEM 18 wheels, and the truck stops very quickly (and weighs 800 lbs more than the GX and has bigger tires!)