Max tire size on stock 18" rims

Graybeard · 08-31-2008, 09:56 AM

Please forgive if this is an old topic, but I can't piece-together the exact answers to my questions doing forum searches. I want to replace the OEM tires (P265/70/18's) on my '05 Titan 4X4 with either Toyo Open Country A/T or H/T light truck tires. My truck also has a PRG 2" levelling kit installed on the front end. I want the absolute tallest AND widest tire that'll fit on the stock rims without doing any additional mods other than, maybe, the pinch weld mod. The replacement tire sizes I've been looking at are LT275/70/18's (33X11), LT285/75/18 (35X11.5), or LT325/60/18's (33X13). I pretty-well know that the 275's will fit the truck without a problem, but will there be issues with the 285's or 325's? If necessary, I'd consider doing the pinch weld mod to get the 285's or 325's to fit, but really don't want to do any additional cutting (mud guards, etc) beyond that. If there's hope for either the 285's or 325's, what other mods would be necessary to get them to fit if the pinch weld mod, alone, wasn't enough? Any help appreciated. Thanx.

NorCal 4x4 · 08-31-2008, 11:01 AM

There are members running the Nitto TG in the 325/60/18, but I wouldn't on stock 8" rims because both Nitto and Toyo state 9.5" rims minimum. [If they thought it was ok on 8" rims, they would sell more, so ...].

The 285/75/18 is good but having a 3-ply sidewall, it weighs a lot compared to their 2-plys, and its height might mess with your torque converter locking up, and for sure will raise your overall gearing. At least you have the BT gears, but with their 66 lbs, you'll notice it, and lose about 2 mpg, especially if you do city or stop and go a lot.

I'd go for the 33.1" LT275/70R18 E if Toyo. At 55 lbs. it weighs 11 lbs. less that the 285/75 and 5 lbs. less than the 325/60. You will only lose about 1 mpg, plus keep most of your current power.
It is also offered in the Michelin LTX A/T 2.

Also, a heavier, shorter, and wider size, LT285/65/18 E is available in the BFG AT KO and Michelin LTX A/T 2.

Graybeard · 08-31-2008, 09:01 PM

Thanks NorCal. That's the info. I needed. I was leaning towards the LT275/70's. However, I'm now concerned about the possible loss of power you eluded to with that bigger tire compared to the stock 265/70's. I don't mind the 1 mpg decrease, but I tow a 7,000 lb., 29 ft. travel trailer and don't want to sacrifice any power for the sake of a slightly larger tire size. That being the case, would I be better-off replacing the stockers with the same 265/70's? I'd really like the slightly bigger tire, but if it means any less power available for towing, I guess I'd rather stick to OR sizing. Any thoughts?

NorCal 4x4 · 08-31-2008, 09:38 PM

The 275/70 is just slightly bigger ... 33.1" vs 32.6" for the 265/70. This won't affect gearing that much, especially not that noticeable with the big tow gears.

You might notice a 55 lbs. tire being very slightly slower off the line, compared to a 43 or 44 lbs. OEM P-metric, but not that much. I think somewhere above 60 lbs. is where it is more noticeable, (my current M/Ts are 73 lbs.). Still quick but ...

The load rating of the 265/70 P-metrics is more than enough for the Titan's maximum capacity. But for an E-rated 33.1" tire, 55lbs. is actually a bargain. And if you do end up overloading your Titan, or going off road, the tires won't be the "weak link".

wesgray · 08-31-2008, 09:49 PM

I have 325/65-18 on stock LE 18s and I dont have any prob. Very miner rubbing on full lock.

NorCal 4x4 · 08-31-2008, 10:08 PM

Quote:

Originally Posted by wesgray

I have 325/65-18 on stock LE 18s and I dont have any prob. Very miner rubbing on full lock.

Yeah you can fit a 35 with a pwm and mud guard removal or modification for no rubbing, (stock rims), but for the OP's case, not the best setup for towing a 29' trailer ... especially if he tows on a grade.

wesgray · 08-31-2008, 10:29 PM

Quote:

Originally Posted by NorCal 4x4

Yeah you can fit a 35 with a pwm and mud guard removal or modification for no rubbing, (stock rims), but for the OP's case, not the best setup for towing a 29' trailer ... especially if he tows on a grade.

that is very true I dont tow very often. He sould go with 285s that would be best.

NorCal 4x4 · 08-31-2008, 10:33 PM

Your Titan looks really tall for a 2.5" level kit ... makes the tires not look that tall. Is it a 4x4 by any chance?

Graybeard · 09-01-2008, 06:41 AM

Thanks again, guys. One more question... the LT Toyo's come in AT and HT models. I'm not off-road very much at all, and most driving is done in-town and on the paved roads & highways; although I am on quite a few gravel roads and in some farm fields to pick-up firewood. The HT's appear to be the best choice for my application, but would there be any advantages to using an all-terrain tire instead? I'm thinking the AT might be a better tire for snow and rain, although the HT is advertised as an all-weather tire. Any advice appreciated. Thanks.

NorCal 4x4 · 09-01-2008, 01:17 PM

Probably a little smoother ride, and perhaps better tread life with the H/T.

For the A/T, more traction in the dirt, mud and snow for the firewood trips, but if you have done it with your OEM tires the H/Ts should work. One huge advantage for A/Ts, (at least in Calif.), is with 4x4 you don't have to chain up with a tire that has a M+S, (Mud & Snow), rating for the first couple of levels of chain controls.

The copy of the H/T spec sheet that I have, does not list M&S, or even mention snow, while the A/T spec sheet does. In Calif. we are still required to carry the chains, but they usually close the highway down if it is bad enough for the highest level chain controls.

Chains are to be avoided, IMO, and one major advantage of having a 4x4 ... and a tire with a M+S rating.

Graybeard · 09-02-2008, 07:46 AM

Thanks again! We don't get a ton of snow here in southeast Missouri, but it does come-a-blizzard every so often. Even though the Toyo H/T doesn't have the M+S designation, does the H/T's "all weather" badge even imply that it's good in snow, or is it just adequate? Up 'til now, and for the type driving I do, I've been getting-along pretty well with the tread pattern on the stock P-metric Goodforayears I'm replacing (only 28,000 miles on 'em, and they're shot!). I don't really want to go overboard by purchasing an A/T tire if the H/T will suffice, but I want to be as prepared as possible in the event the A/T might prove more useful. I know it's a toss-up, but I'm leaning toward the H/T unless there's something you could add that would swing me the other way. Any parting thoughts before I run to the shoe store? As usual, any additional help is definitely appreciated!

Pops · 09-02-2008, 09:37 AM

I'm running 325/60-18 on OEM wheels with a little over 15k miles on them and aboslutely love 'em. I'd suggest this setup to anyone in a heartbeat who offroads once in awhile and I've been running them at 38psi-40psi, VERY Nice IMO. Just be prepared for 11.5-12.5 MPG avg with the Big Tow package due to the 60-lb ea tire weight is the only downside.

Here's some pics:

Offroad Pics - RedRock Canyon, NV.

Graybeard · 09-02-2008, 11:04 AM

Quote:

Originally Posted by Pops

I'm running 325/60-18 on OEM wheels with a little over 15k miles on them and aboslutely love 'em. I'd suggest this setup to anyone in a heartbeat who offroads once in awhile and I've been running them at 38psi-40psi, VERY Nice IMO. Just be prepared for 11.5-12.5 MPG avg with the Big Tow package due to the 60-lb ea tire weight is the only downside.

Here's some pics:

Offroad Pics - RedRock Canyon, NV.

Awesome! Looks like a good time!! Thanks for the info & pix!!

NorCal 4x4 · 09-02-2008, 11:04 AM

Quote:

Originally Posted by Graybeard

Thanks again! We don't get a ton of snow here in southeast Missouri, but it does come-a-blizzard every so often. Even though the Toyo H/T doesn't have the M+S designation, does the H/T's "all weather" badge even imply that it's good in snow, or is it just adequate? Up 'til now, and for the type driving I do, I've been getting-along pretty well with the tread pattern on the stock P-metric Goodforayears I'm replacing (only 28,000 miles on 'em, and they're shot!). I don't really want to go overboard by purchasing an A/T tire if the H/T will suffice, but I want to be as prepared as possible in the event the A/T might prove more useful. I know it's a toss-up, but I'm leaning toward the H/T unless there's something you could add that would swing me the other way. Any parting thoughts before I run to the shoe store? As usual, any additional help is definitely appreciated!

I'd say w/o a M&S mark, the all season wouldn't be very good in the snow, and would require chaining up at the same time they would make cars do it. But if you've been fine with the OEM, the HTs will probably make you happy. I hate putting on chains, so I'll stick with a M&S tire, but I live near the mountains. Please post some pics when whatever you get are on.

Graybeard · 09-02-2008, 04:02 PM

Quote:

Originally Posted by NorCal 4x4

I'd say w/o a M&S mark, the all season wouldn't be very good in the snow, and would require chaining up at the same time they would make cars do it. But if you've been fine with the OEM, the HTs will probably make you happy. I hate putting on chains, so I'll stick with a M&S tire, but I live near the mountains. Please post some pics when whatever you get are on.

I'll get the camera ready, and as soon as I make a decision and get the new rubber I'll post some pictures - - although it might be a couple of weeks. Really appreciate all the help!