So does the 275/65/20 fit in the space tire wheel well?
OE GX 550 Premium 20" Wheels w/Aftermarket Off-Road or All-Terrain Tires
- Thread starter Rooster_17
- Start date
have pictures? I am hoping to get mine in Jan 2026
Ray, I’ll address your spare tire concern with what I know.
Short version:
Right now, before getting your GX, is go by a tire shop that has the same exact Cooper Discoverer RT you see in my pic. Use that as your gauge. Then stand whatever 275/65/R20 you’re considering next to it. That’s an easy test. No mounting required at this point.
Long version:
A couple initial caveats: 1) My GX is a ‘24, yours I guess will be a ‘25 or ‘26. So I cannot be absolutely positive that the provided spare tire space is/will be exactly the same diameter as my ‘24. Maybe Toyota-Lexus slightly increased that space, volume without announcing it. 2) You cannot fully rely on stated manufacturer nominal specs, or, that all 275/65/R20 will be the same true diameter.
I currently have the Cooper 33.7-ish spare (stated to be 33.66) mounted, inflated and fully seated up into the spare tire space. It rests against all 3 or 4 touch points that guide it into place as you crank it upwards. It is fully seated vertically and laterally with no remaining space, none. I do not use a 5-tire rotation, so it’s okay to be a different tire. I only wanted an E rating, with nearly the same diameter as the mains.
That’s why I’m doubtful that a true 275/65/R20 would fit upwards all the way. However, an actual ‘shy’ 275/65/R20 non-E (significantly deflated, spray lube on touch points) might have a small chance of fitting.
Before I committed to my new tires path I went to my local DT store, and we mounted up the Cooper spare I thought would just barely fit. It did. It’s a very tall 275/70/R18 E, actual about 33.7 (vs. a nominal tire calc of 33.2). It just, just fits as I describe above.
Next, I ordered in my 4 main tires, the Toyo AT3 E, in size 285/70/R18. It is an actual ‘shy 34’, coming in at 33.7, same as my spare.
That’s how I did it, after looking at several websites - and then doing a hands on confirmation.
You can see the Cooper spare and Toyo main side by side in the photos before we mounted all the tires.
Best to you, you will love your GX!
-DJ
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Thank you so very much for you response and knowledge. It was very kind of you. After reading your response I realize that I have never used my spare tire for anything other than an emergency and then thats for a very short period of time. I rarely take my vehicles off road except maybe a few times a year and that's not for anything challenging or treacherous. So initially, I will not change my spare tire/wheels and only change my tires on the other four. If it becomes an issue, again I will follow your lead reading 'shrink' the tire to fit the space. I will definitely follow your advice about standing them next to each other to start if off and when I make the call I will ask the installer to verify the clearance ( lack of rubbing) after the tires are mounted.Ray, I’ll address your spare tire concern with what I know.
Short version:
Right now, before getting your GX, is go by a tire shop that has the same exact Cooper Discoverer RT you see in my pic. Use that as your gauge. Then stand whatever 275/65/R20 you’re considering next to it. That’s an easy test. No mounting required at this point.
Long version:
A couple initial caveats: 1) My GX is a ‘24, yours I guess will be a ‘25 or ‘26. So I cannot be absolutely positive that the provided spare tire space is/will be exactly the same diameter as my ‘24. Maybe Toyota-Lexus slightly increased that space, volume without announcing it. 2) You cannot fully rely on stated manufacturer nominal specs, or, that all 275/65/R20 will be the same true diameter.
I currently have the Cooper 33.7-ish spare (stated to be 33.66) mounted, inflated and fully seated up into the spare tire space. It rests against all 3 or 4 touch points that guide it into place as you crank it upwards. It is fully seated vertically and laterally with no remaining space, none. I do not use a 5-tire rotation, so it’s okay to be a different tire. I only wanted an E rating, with nearly the same diameter as the mains.
That’s why I’m doubtful that a true 275/65/R20 would fit upwards all the way. However, an actual ‘shy’ 275/65/R20 non-E (significantly deflated, spray lube on touch points) might have a small chance of fitting.
Before I committed to my new tires path I went to my local DT store, and we mounted up the Cooper spare I thought would just barely fit. It did. It’s a very tall 275/70/R18 E, actual about 33.7 (vs. a nominal tire calc of 33.2). It just, just fits as I describe above.
Next, I ordered in my 4 main tires, the Toyo AT3 E, in size 285/70/R18. It is an actual ‘shy 34’, coming in at 33.7, same as my spare.
That’s how I did it, after looking at several websites - and then doing a hands on confirmation.
You can see the Cooper spare and Toyo main side by side in the photos before we mounted all the tires.
Best to you, you will love your GX!
-DJ
Thanks again.
PS I really like your set up.
Do you think if I swapped the wheels to vossen hf6-1 (Introducing the Vossen HF6-1 Wheel) with those Toyo OC AT3 275/60/20 tires it would fit w/o rubbing?
I think it would, I believe others have done it.
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Great info on this thread. Thanks all for sharing. I have a Noori Green Prem+ that I'm looking to put new wheels on.
Confirming 275/65/20 will fit keeping everything stock, without a leveling kit or any trimming or suspension mods?
Also, the wheel I'm likely getting are 20x9 with a +18 offset. How much will that offset effect things?
Confirming 275/65/20 will fit keeping everything stock, without a leveling kit or any trimming or suspension mods?
Also, the wheel I'm likely getting are 20x9 with a +18 offset. How much will that offset effect things?
From my understanding if you get wheels with a different larger offset (+ 30's vs +18) you might not fit the 275/65/20's and might need to go down to 275/60/20's. I have not done it yet and like you I am waiting to get mine. I will attach a link that shows one GX550 Aftermarket Wheel & Tire Thread.
20" Vossens HFX-1
275 60 R 20 - Toyo Open Country Tires
GX550 Forum Photos
GX550 Forum Photos
