So I just upgraded to BFG's KO2 size 285 65R18. Is it absolutely necessary to change the OEM spare to the same tire/size? I would understand wanting the same tire in worst case scenario of needing it out on the trail and not wanting to depend on the OEM to get back to civilization.
5th Tire/Spare
- Thread starter samster747
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It's about number of rotations vs reliability. If you have an LX, your KO2s are 1.5" bigger than stock. Even if you assume that the KO2s "run a little small", you're still ~1" over and that corner will rotate at a different speed than the other 3.
I can't tell you exactly how bad that would be or what you would break, but it can't be good for the diff/trans especially if you're on pavement. If you're talking about limping off a trail and then getting flat towed home, then that might be a different story.
I can't tell you exactly how bad that would be or what you would break, but it can't be good for the diff/trans especially if you're on pavement. If you're talking about limping off a trail and then getting flat towed home, then that might be a different story.
it’s a bad idea. Could do serious damage to the Torsten center diff. I have even heard stories about not letting one tire get too far worn, or rotating in a new spare on well worn tires.
Maybe @cruiseroutfit can give the techie details.
Maybe @cruiseroutfit can give the techie details.
I am not so worried about Torsen, but different tire size on same axle may trigger traction control, esp around corners.
Rev/Mile stats and tire size: LT285/65/18 + 18” stock rims and KDSS
Rev/Mile stats and tire size: LT285/65/18 + 18” stock rims and KDSS
What year is your LC? Does it rub on KDSS bar?
If it’s a cost thing put some other cheaper tire in the same size on as a spare. Or, understand that another tire in your rotations slows the wear on the other four.
@samster747 I just had this decision (same size tire, different brand) - after rolling the spare (factory tire) next to the mounted new tires, it was an easier decision. If you aren't going to replace, I'd recommend carrying a good patch kit, air compressor, etc.
FWIW: In the past year, I've needed a spare twice and both times, it'd of been silly expensive to get a tow (and only had cell for one of them).
Plus - looks SWEET when you're cleaning filth out of the underside of the truck
FWIW: In the past year, I've needed a spare twice and both times, it'd of been silly expensive to get a tow (and only had cell for one of them).
Plus - looks SWEET when you're cleaning filth out of the underside of the truck
This is an easy one. For sure get a matching spare and do a 5 tire rotation. Even if you never need a spare, your tires will last long enough to cover the extra cost. And if you do need a spare......you have no worries about mechanicals, electronics, or traction.
There is another advantage to an identical spare..
If it is included in your five tire rotations and hypothetically you wear everything halfway, if you then get a flat and replace one, you can keep rolling on four of the originals and not have one new tire be oversized. Then when the remaining four wear out, throw the unused tire back into the five tire rotation. Assuming you stick with the same model anyway.
There are good reasons to have five matching tires. I don’t, because one of my wheels is cosmetically damaged and I don’t want it in the rotation, so I’d lose the benefit of the extra wear miles for the whole set. But you can be sure I run a same-size spare to avoid causing drivetrain problems if I am somehow forced to drive hundreds of miles on it.
If it is included in your five tire rotations and hypothetically you wear everything halfway, if you then get a flat and replace one, you can keep rolling on four of the originals and not have one new tire be oversized. Then when the remaining four wear out, throw the unused tire back into the five tire rotation. Assuming you stick with the same model anyway.
There are good reasons to have five matching tires. I don’t, because one of my wheels is cosmetically damaged and I don’t want it in the rotation, so I’d lose the benefit of the extra wear miles for the whole set. But you can be sure I run a same-size spare to avoid causing drivetrain problems if I am somehow forced to drive hundreds of miles on it.
- Thread starter
- #10
Thanks for the replies. My question was basically because some vehicles don't have full size spares (donuts). The manual recommends a 5 tire rotation however, I do have the HE. I was leaning on just getting a matching 5th tire and using it exclusively as a spare. Don't really want to spend another $300 for a matching wheel. I'm assuming unbalanced tread wear won't be too much of an issue if I need to put on the spare vs different tire size.
Don’t most donuts have same diameter as main tires...it is just that they are thinner ??
matching HE is more like $600
I think donuts are usually used for 2wd cars and recommended to be used on non-driveline corner. i.e, my old rwd GS350 said to use donut on fronts only.
- Thread starter
- #13
you may be right...not quite sure.
- Thread starter
- #14
haha damn...maybe I'll stick to 4 tire rotation.matching HE is more like $600
I think donuts are usually used for 2wd cars and recommended to be used on non-driveline corner. i.e, my old rwd GS350 said to use donut on fronts only.
I have the same size tire. I bought five and do five tire rotations. The added cost isn't significant, your tires will last 20% longer, and you don't have to worry about potential damage.
- Thread starter
- #16
I dunno...shell out another $600 for matching HE wheel? The wife will not be happy...
The stock wheel back there is actually a good reason. Plus, I’ve found the spare tire mounting stops can make scuffs on the wheel.. and that would be a crime for those nice bronze BBS things.
Matching 5th tire would work great. Your assumption is correct, even if the other tires have worn you won’t cause damage running that new tire.