Considering buying a GX

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803PalmettoLX

803PalmettoLX

Joined
May 10, 2025
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Location
SC
Hi All,
I currently have an 03 LX which is my weekend driver, but I'm considering a 2019-23 GX as a daily driver as my vehicle needs are soon changing.

Would like to do light mods upon purchasing, so my main question is: has anyone had any rubbing issues with 275/65/18 BFG KO3s?

I understand there are issues with fitting a bigger spare, would this be solved by deflating or airing down? Or will I definitely need a lift kit?

Also, does the GX require premium 93 octane?

Thanks in advance!
 
Here is a good example of your chosen tire fit.

sPaulp

Thread '275/65/18 BFG’s installed-fits in spare location too'

My 1.75” lift goes on next week, but I went ahead and installed the KO2’s today and I’m happy to report no rubbing in stock form and the spare fits as well (I chose 255/70/18 for the spare so it’s the same diameter but a little skinnier to tuck in the spare location-worked perfectly). Surprisingly, my speedo is dead on which I thought for sure it would be a little off - I verified with GPS. These pics are when I pulled into the driveway and haven’t cleaned the wheels/tires.

970B276A-A32B-42AF-8E1E-2D33099FF77C.jpeg


27A5C190-2D53-4720-8400-30646A2038D7.jpeg


7BD27C64-14D1-4A5C-810C-0E931988142E.jpeg


6D707E86-6398-4F36-8720-497BF7D4B0DC.jpeg
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I think you can make the spare fit. Its much more likely to fit wit no hitch....or supposedly the 4Runner hitch... I just got a 265/70/18 under there by using the KDSS spacers and its supposedly 1/2" taller. (can be seen in my signature link)
 
iwashmycar said:
Here is a good example of your chosen tire fit.

sPaulp

Thread '275/65/18 BFG’s installed-fits in spare location too'

My 1.75” lift goes on next week, but I went ahead and installed the KO2’s today and I’m happy to report no rubbing in stock form and the spare fits as well (I chose 255/70/18 for the spare so it’s the same diameter but a little skinnier to tuck in the spare location-worked perfectly). Surprisingly, my speedo is dead on which I thought for sure it would be a little off - I verified with GPS. These pics are when I pulled into the driveway and haven’t cleaned the wheels/tires.

970B276A-A32B-42AF-8E1E-2D33099FF77C.jpeg


27A5C190-2D53-4720-8400-30646A2038D7.jpeg


7BD27C64-14D1-4A5C-810C-0E931988142E.jpeg


6D707E86-6398-4F36-8720-497BF7D4B0DC.jpeg
  • Like
  • Love

I think you can make the spare fit. Its much more likely to fit wit no hitch....or supposedly the 4Runner hitch... I just got a 265/70/18 under there by using the KDSS spacers and its supposedly 1/2" taller. (can be seen in my signature link)
Click to expand...
Thanks, is there any difference between KO3s and KO2s? KO3s maybe a bit bigger treadwise?
 
803PalmettoLX said:
Hi All,
I currently have an 03 LX which is my weekend driver, but I'm considering a 2019-23 GX as a daily driver as my vehicle needs are soon changing.

Would like to do light mods upon purchasing, so my main question is: has anyone had any rubbing issues with 275/65/18 BFG KO3s?

I understand there are issues with fitting a bigger spare, would this be solved by deflating or airing down? Or will I definitely need a lift kit?

Also, does the GX require premium 93 octane?

Thanks in advance!
Click to expand...
In considering tire size, you may also want to consider if a larger spare will fit underneath. Unless, you plan on a rear tire carrier of some sort.
Anything you can fit in your spare tire compartment will not have a problem with rubbing without a lift. Albeit, there may be a slight rub when at full compression and in lock-to-lock.
 
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803PalmettoLX said:
Also, does the GX require premium 93 octane?

Thanks in advance!
Click to expand...
It calls for it, but there are quite a few who put in regular. My stance is that I only put in quality regular gas, typically shell or bp, but most often shell and I have never had an issue.

I have put about 90k miles over the last 4 years on my 2013 and my wife has put 60k miles in the last 3 years in her 2020 all on regular.
 
803PalmettoLX said:
Also, does the GX require premium 93 octane?
Click to expand...
I've only run 91, which here in California is the best you can get unless you go to a gas station that sells racing fuel at >97 octane, which there are a couple those stations around for $$$.
Running regular just seems to lower my MPG.
 
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I've never once used premium. I use 87, which is lowest octane locally. When I go out west I use 85 where it is available. I'm at 58k, 35k of which I put on, no issues. Opinions vary but I've never heard of an actual issue from a user, just anecdotes about not using premium - authored by premium users.
 
You might also be able to get an 87 octane tune for a GX460. I have a 87 tune on my 470 and have exclusively ran 87 (or 85 at elevation) since gas got pricey in 2021/2022.
 
Anecdotally, a few months ago I made a ~600mi round trip, filled up with regular 87 before I left, and 91 before the trip home, both directions I was 99% freeway with cruise control between 70-75 and I returned 21.5mpg on the trip home (with premium), vs 18mpg on the way out. I don't remember if I had a strong tailwind in either direction but my starting and ending destination were about the same elevation and I took the same stretch of freeway out and back. I was surprised by a nearly 20% change in economy, I am doing the drive again in late April so will test again at that time to see if I get a similar result. I will drive out with Premium and return on Regular this time to see if that makes any difference.
 
NorthwoodsGX said:
Anecdotally, a few months ago I made a ~600mi round trip, filled up with regular 87 before I left, and 91 before the trip home, both directions I was 99% freeway with cruise control between 70-75 and I returned 21.5mpg on the trip home (with premium), vs 18mpg on the way out. I don't remember if I had a strong tailwind in either direction but my starting and ending destination were about the same elevation and I took the same stretch of freeway out and back. I was surprised by a nearly 20% change in economy, I am doing the drive again in late April so will test again at that time to see if I get a similar result. I will drive out with Premium and return on Regular this time to see if that makes any difference.
Click to expand...
If in fact you do, do that trip again, reverse your octane so you have 91 going out and 87 on the way back. That should absolutely either debunk or confirm my position of "better MPG with higher octane".
 
At least with my older 2UZ, there was no substantial difference in fuel economy between 87 and 91 octane. It would also take many months of testing with both 87 and 91 to establish a baseline averages and then compare them (and, the ECU would probably need a reset between gas tanks as learned fuel trims and timing parameters would need to be re-learned). 91 octane is at least $0.50/gallon more around here, so the fuel economy increase would need to be substantial to recoup the increased fuel cost.

What the actual difference may be is ethanol vs. non-ethanol fuel. Missouri is unfortunately a mandatory 10% ethanol state for 87 octane fuel (E10) - as is Minnesota. 91 octane is exempt from that rule (at least in MO) so it's usually ethanol-free (I run 91 in all of my small engines to avoid damage that E10 can cause to carburetors). Ethanol has a lower energy density than straight gasoline. In my rig I notice that my fuel trims seem to drop when I travel out-of-state and fill up with non-ethanol fuel. I haven't tracked fuel economy with E0 vs. E10, but lower fuel trims should directly correlate to improved fuel economy.
 
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91 octane in MN is exempt from required ethanol, but you will know at the pump whether or not the fuel has ethanol, e0 is about $0.70/gallon more expensive. I buy gas at a lot of stations that offer both 91 with ethanol and 91 or 93 "clear" or "non-oxygenated" fuel which is e0. I bought the fuel in MN and IL, and in both cases it contained at least 10% ethanol but I know in MN we allow up to 15% ethanol in some situations so its possible I was comparing e-10 and e-15. I will need to pay attention to that when we make our trip later this month. Ultimately, there are too many variables to say for certain how much better 91 octane is compared to 87 octane in a test like this, but by running the experiment a few times we can probably conclude that one is better than the other or that other variables have a more significant impact in fuel economy.
 
NorthwoodsGX said:
91 octane in MN is exempt from required ethanol, but you will know at the pump whether or not the fuel has ethanol, e0 is about $0.70/gallon more expensive. I buy gas at a lot of stations that offer both 91 with ethanol and 91 or 93 "clear" or "non-oxygenated" fuel which is e0. I bought the fuel in MN and IL, and in both cases it contained at least 10% ethanol but I know in MN we allow up to 15% ethanol in some situations so its possible I was comparing e-10 and e-15. I will need to pay attention to that when we make our trip later this month. Ultimately, there are too many variables to say for certain how much better 91 octane is compared to 87 octane in a test like this, but by running the experiment a few times we can probably conclude that one is better than the other or that other variables have a more significant impact in fuel economy.
Click to expand...
IMO 91 octane E0 will likely be superior to 87 octane E10 from a MPG perspective (how much, I'm not sure though), but form a cost perspective it's probably not :). I really wish we didn't have the ag-lobby handout law here in MO so E0 was widely available. I ran a number of E0 tanks out our trip to the Gulf Coast last week and noticed my fuel trims dropped to near-zero. The rig seemed to run about the same, however, so if there was a performance difference, I did not notice it.
 
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