Largest tire that fits in underbody spare tire carrier

[Guest]

22 hours ago, RainGoat said:

Here we go again….

I’m looking to find the largest 17” rim tire that will fit in the stock location underneath, with an OEM hitch. Reportedly the limit is 31”.  I know a 265/70R17 (stock 5th Gen T4R tire) most definitely will not fit.

 

I’m getting Toyo AT3s for my Q & these are my options:

 

Wt Tread  Dia  Width  Tire Size    Speed/Load

35 13.0   30.9    9.3 P235/75R17  108S/SL       

35 13.1    30.6   9.8 245/70R17 110T/SL      

42 16.1    30.6   9.8 LT245/70R17 119/116/RE

37 13.2     31.1   10.2 255/70R17   112T/SL       

38 13.3   30.6  10.7   265/65R17   116T/XL      

https://www.toyotires.com/product/open-country-at3/

 

1st Choice: P235/75R17 closest to 31”- ?fit?

 

2nd Choice: 245/70R17

 

265/65R17 should fit but I’m not sure that the XL load rating won’t mean it’s too stiff. SL & XL are both 4 ply but the XL requires more pressure at Max Load - which, honestly, is counterintuitive to me.

 

I think the 255/70R17 will be too big 

 

I think the LT245/70R17 will be too stiff as this truck is usually unloaded 

 

Has ANYONE out there tried a P235/75R17?

That size shows 30.9" diameter, which is essentially a 31". From previous posts, that size will not fit without making contact with phb. I'd recommend any of the 30.6".

[zadrozny91]

my tires are goodyear duratracs 265/70/16 (30.6") and they wouldn't fit so I got a spare 245/75/16 (30.45") of another brand and it fit fine, had to tuck it under the hitch first and then it wouldn't rub the panhard bar, probably 1/2" clearance as stated

[RainGoat]

my tires are goodyear duratracs 265/70/16 (30.6") and they wouldn't fit so I got a spare 245/75/16 (30.45") of another brand and it fit fine, had to tuck it under the hitch first and then it wouldn't rub the panhard bar, probably 1/2" clearance as stated

Hmm, that’s disappointing to hear. Definitely means the 30.9” is out. Now I’m worried about the 30.6”. The next largest size is the stock 245/65R17 (29.5”) - it would be nice to go up a little. Did you actually measure your Duratracs to see if their actual size matched their calculated size? I can’t imagine the AWD will like a different diameter tire & we usually have 1-2 hours of mountain highway driving to access the Cascades

[zadrozny91]

15 hours ago, RainGoat said:

18 hours ago, zadrozny91 said:

my tires are goodyear duratracs 265/70/16 (30.6") and they wouldn't fit so I got a spare 245/75/16 (30.45") of another brand and it fit fine, had to tuck it under the hitch first and then it wouldn't rub the panhard bar, probably 1/2" clearance as stated

 

Hmm, that’s disappointing to hear. Definitely means the 30.9” is out. Now I’m worried about the 30.6”. The next largest size is the stock 245/65R17 (29.5”) - it would be nice to go up a little. Did you actually measure your Duratracs to see if their actual size matched their calculated size? I can’t imagine the AWD will like a different diameter tire & we usually have 1-2 hours of mountain highway driving to access the Cascades

don't quote me on this 100%, I might have not tried hard enough with the duratracs in 265/70/16. The 245/75/16 is very close in diameter and it fit and I also believe tread depth and style is a deciding factor. Not sure if there are different style hitches too, some might have more space than others. Yes, I also didn't want a stock size spare with a 30.6" regular tires for the same reason. I can take some dimensions if that would help you. Another trick would be to keep the spare deflated and only inflate when needed, that way they tire will be a bit smaller and easier to fit

[RainGoat]

I can take some dimensions if that would help you.

When convenient, if you could just measure your Duratracs for an actual diameter. Tires often aren’t the size the tire calculators say they should be - manufacturer variance I suppose. Unfortunately, they’re usually smaller - which won’t help me in your case but might if Toyo runs small.