dclaytor

New 2013 GX white / sephia owner here: Base w/ convenience, comfort plus, 3 zone HVAC, steering wheel, nav, tow package, tanneau, cargo mat

First thing I had to address was the headlight situation. I foolishly thought the projector beams were HID powered. Thanks to members here (Koz, Luke27617 & others), I was able to quickly come up with a solution:

Headlights: Xtreme Digital HID: Philips Bulbs, 4300K
DRL / High Beam: VLED 5K WHITE 1800LM LED
Fog: VLED 5K WHITE 1800LM LED
Side Marker: LED 5K White 194 10 LED
Reverse Lights: Putco 921 LED Stick
Brake Lights: Putco 921 LED Stick

After installation yesterday and test drive last night, verified the overall light setup is great, and the HID low beam setup is awesome - the 1800 lumen LED's are bright, and the color temp matches well.

I'm disappointed in the Putco backup lights, I'm guessing the led layout is wrong (one, large outward facing vs. 6-10 facing sideways), as the light emitted does not hit the reflector much, if at all. I expected these to be like rear 'headlights', so when I'm looking over my shoulder I can see, but not at all unfortunately. I have a long driveway with large tree to maneuver around, difficult to backup at night - guess I need to learn to trust the backup camera.

Now I'm out to solve my next problem, the stock wheel look and tire size / type. Thinking I will have the permachrome dark chrome treatment done to the wheels, and get larger Michelin LTX M/S2 tires. Concern here is that the overall wheel diameter change could impact the electronic stability control / 4wd slip sensors? Any feedback here would be great.

We just passed 1500 miles, and so far this is a great rig, we are both very happy with the purchase. We knew there was 2014 refresh was coming, but we were under time pressure to replace her old vehicle, and it turns out we actually prefer the old look. Seeing the 2014 list prices, I'm wondering if I could have negotiated better.

Looking forward to ski trips to Tahoe & off road camping with the dirt bikes with this rig. It's cool to have a forum with knowledgeable members, given the quantity this vehicle is sold in.

We looked at Q7, GL350, Yukon, but the GX was my choice all along. Sticker was 60 & we paid 53 + ttl few months ago (Silicon Valley).

Koz

I have changed the tires on my GX to 275/65/18 and still used the OEM wheels. I only did this because I needed LT tires for towing. The 275/65/18 was the closest overall diameter LT-LTX MS2 to the OEM size. It turned out that with this bigger size I was still able stay within the OEM alignment spec and it did not have any noticeable negative effect on the ride or handling (lucky). The only mod I had to do was heat the plastic inner fender well and push it in approx a 1/4".

Two important aspects to remember are the wheels/tires must have the clearance and offset that will work with the OEM vehicle's suspension and braking system. Also, the overall diameter of the tires. Changing the overall tire diameter will also change the final gear ratio. For the best ride dynamics, you want to stay as close the OEM specs as possible. If you increase the wheel diameter (lets say 18” to 20”) you will need to also change the tire size to maintain (or stay as close) the overall diameter OEM’s tire. Example; the OEM tire’s overall diameter is 30.5” (265/65/18) and you would want to stay as close as possible to that size as possible. The closest 20” tire to the OEM size is a 285/50/20 (31.3” overall diameter). Here is the tricky part, when changing to a different sized wheel it is critical that the new wheels have the right offset and width that will provide enough clearances and does not have a negative effect on the overall ride. Being that you went from a 60 series tire to a 50 you will now need to increase the width of the wheel from 8” to 9”. Doing this may in-turn need to change the offset. Regardless of what anyone tells you, depending on far you deviate from the OEM’s design specs, the more affect it will have on the ride and handling (probably negative). Whatever changes you make you have to make sure you stay within the range of the vehicle’s OEM design. Once you have exceeded this range you will need to modify the OEM design. Again, stay as close as possible to the OEM spec and if you want/need to go beyond that spec make sure you consult a wheel and tire expert. It could get real ugly and/or expensive if you don’t do it right!

Koz

Quadro

There is LTX MS/2 with exact OEM size though they lack Green X technology. I have no idea what real world difference that makes. They are still 720 AA. The ones with Green X can not be had with OEM size as Koz pointed out.

dclaytor

Thanks for the feedback / warning, I'm going to stay with the stock wheel diameter.