Offtopic, but I need to pick someone's brain.

Recently purchased a 2023 Outlander sitting on 20 inch wheels. Whats the best way to determine if I can fit 16 inch wheels (for mounting A/T tires)?

I've got some 16 inch Sparcos that should fit the Outlander bolt profile as I believe it matches Rav4 and Corolla patterns. Should I just pull the 20 inch off and hand fit the 16 or should I consult manufacture info? I haven't found much after a lot of google searching. Outlander forums are kind of dead (just aren't that many enthusiasts out there).

Not so offroad friendly 20's:

 

https://www.tacomaworld.com/forums/off-topic-discussion.14/

 

First and foremost you need to see if you will clear your caliper and rotors / drums etc. If you have the rims in hand slap one on there and find out.

 

Put the 16s on and tighten 2 or 3 lugs nuts down and make sure the 16s will clear the all of the brake components (mainly the caliper) and also your ball joints, tie rods and such. Give the wheel a good spin and make sure its not rubbing, binding on anything. The Different wheels could also have a different offset so make sure you turn the steering wheel back and both as well and make sure you have clearance for the tire. Also check the center of the wheels fit around your axle housing on the knuckle and that should do it

 

If you have the 16" wheels already bolt one on - both front and back.

Check for brake clearance which is the most common issue & also around the strut/spring mount. Make sure to turn the steering full lock in both directions.

Keep in mind suspension articulation too, if you have the jack positioned so the suspension is at ride height that is better.

If everything seems to be a pass so far get a tire in the size you want mounted up and try again - usually any tire shop will give you a used tire, it just needs to be the right size for a test.