Replace 2 or all 4 tires? (7 Viewers)

[pelagoram]

I've been poring over past posts for the past few hours, but can't seem to find a definitive answer to my question. I aplogize if this is repetitive.

Just had a blowout of my right rear tire on my '91 FJ-80, followed a few miles later by a blowout of the spare (pretty sure the spare probably was not in great shape to begin with)

The remaining 3 tires have a pretty good amount of tread left on them, so my thought is to get two new tires of the same model and size as the remaining 3 and put those on the rear and put one of the three current tires as the spare.

Is this a bad idea? Should I replace all 4? Am I setting myself of for trouble?

I've read some posts that say a difference in wear won't be enough to worry about, and others that seem to say the opposite.

Thanks, in advance, for any help. . .

P

 

[98 SNAKE EATER]

It's ALWAYS better to buy 4 (or 5), but if the difference isn't severe, I wouldn't worry about it

On the other hand, you could buy 1 replacement tire and have it shaved to match the others

 

[RetiredLifeguard]

I'd either buy 1 and carve it down to match or, go for 4 or 5. When the tread gets thin enough on my tires, I think I'm going to buy 5 and try the 5 tire rotation method. Is anyone here doing the 5 tire rotation shown in the owners manual?

 

[98 SNAKE EATER]

Is anyone here doing the 5 tire rotation shown in the owners manual?

I am

Every 3k miles (at least once a month)

I'm running BFG MT's which see A LOT of long distance runs and rotating all 5 makes quite a difference

 

[Kalawang]

I don't understand why anyone would want to shave down a tire to match. I think it would take care of itself. I'd go for the single and use up the set and then buy 4 more, using the single as a spare.


Kalawang

 

[98 SNAKE EATER]

I don't understand why anyone would want to shave down a tire to match. I think it would take care of itself. I'd go for the single and use up the set and then buy 4 more, using the single as a spare.


Kalawang

There are number of reasons for doing so (Radial pull, wheel speed, matching looks, etc.)

Some manufacturers with more high tech AWD systems actually specify that tires should not have a difference exceeding 1/16" or it can cause overheating in the diffs and transfer case (this usually applies to limited slip diffs)

That being said, our Cruisers aren't so picky, but if I had tires with half life tread or less and needed to buy 1 replacement tire, I'd shave it

 

[Tools R Us]

When selling tires (your $$) most tire dealers will push buying 4, but when you have a road hazard replacement (their $$) they have no problem just mounting one. It's been about 4 years since my rig has a set of matched tires, no issue.

My bigger issue would be why the blowout? Modern tires don't typically have issues, what is the date code on them, if over 4 years old I would replace all of them.

 

[sandcruiser]

I don't know how it affects the center diff, but normally I would just replace 2 tires, and put the *best* of the remaining three as the spare. Why the best? Because I would replace the other 2 tires within a reasonable timeframe... maybe 5 or 10K miles.

I could be wrong, but I don't think that difference in diameter is going to thrash your center diff. It isn't a huge difference.

This is all assuming that the extra couple of hundred bucks is significant to your expenses. If the two leftover tires are closer to 50% of their life, maybe get 4 tires and put those 2 on craigslist or something.

That's how I would do it.

 

[pelagoram]

Tires

So, the three good tires are BF Goodrich 31 1050's - they've probably got 2/3 tread left. Snake Eater - when you say our Cruisers aren't that picky - do you think I could get away with this difference on two of my tires? How much of a difference is too much?

I can get 2 new ones of the same tire for $200 each, or I can get 4 new Spectra A/T 31-1050's for $125 each, so a total of $400 vs. $500.

I'm leaning towards doing all 4 of the Spectra's - anyone have any experience with this brand?

As to the cause of the blowout - looks like I picked up a nasty chunk of metal somewhere in the road. As for the why the spare blew out - who knows. . . it was the spare left by the PO so not sure of its history. Live and learn. . .


P

 

[98 SNAKE EATER]

I don't know how it affects the center diff, but normally I would just replace 2 tires, and put the *best* of the remaining three as the spare. Why the best? Because I would replace the other 2 tires within a reasonable timeframe... maybe 5 or 10K miles.

I could be wrong, but I don't think that difference in diameter is going to thrash your center diff. It isn't a huge difference.

This is all assuming that the extra couple of hundred bucks is significant to your expenses. If the two leftover tires are closer to 50% of their life, maybe get 4 tires and put those 2 on craigslist or something.

That's how I would do it.

In theory, having different sized tires front and rear can cause the center diff to overheat because it has a viscous coupler which acts somewhat like a limited slip differential...

I doubt you would see the effects at low speed, but that multiplies greatly at high speeds

Think of it like having a limited slip rear diff on a muscle car and putting odd sized tires left and right

You'd eventually burn up the LSD because of the difference in speed (same thing applies to our center diffs)

That being said, our front and rear diffs are open, so you probably won't have any diff issues running a slightly different tire heights left and right

So, the three good tires are BF Goodrich 31 1050's - they've probably got 2/3 tread left. Snake Eater - when you say our Cruisers aren't that picky - do you think I could get away with this difference on two of my tires? How much of a difference is too much?

If your remaining tires have 2/3rd tread left, I wouldn't sweat it, just buy a new replacement and add it to the rotation

If you're using the OEM 5 wheel rotation, mount the new tire on the left rear so it gets the most usage before returning to the spare location....

I wouldn't shave the new rubber unless the old ones are 1/2 tread or less

 

[RetiredLifeguard]

In the old days we were told that you should only rotate radial tires front to back. If your tire started out on the drivers side, it had to stay on the drivers side for the life of the tire and that moving a tire from one side to the other was a very bad thing. What has changed? Has tire design and construction changed or were we misinformed.

 

[FirstToy]

The remaining 3 tires have a pretty good amount of tread left on them, so my thought is to get two new tires of the same model and size as the remaining 3 and put those on the rear and put one of the three current tires as the spare.

Sounds like a solid plan. Put the two new tires on the front and you are good to go.

bias ply cannot switch sides but radials are good for crossing over

 

[98 SNAKE EATER]

In the old days we were told that you should only rotate radial tires front to back. If your tire started out on the drivers side, it had to stay on the drivers side for the life of the tire and that moving a tire from one side to the other was a very bad thing. What has changed? Has tire design and construction changed or were we misinformed.

I know I'll get a lot of people that disagree with me on this one, but that only applies to old bias-ply tires and of course, modern unidirectional and asymmetrical tires....

Goodyear's take on this:

Tire Myths...and Reality - More Facts - Car Care - Motor Trend

 

[sandcruiser]

if you still have 2/3 tread left, then I would get 2 new tires, up front, and roll.

Unless you are looking to upgrade your tires, in which case.... get all 4!

Also: you don't have a viscous center diff in a 91. (at least, I don't think you do) so don't worry about the minor size differences.

 

[98 SNAKE EATER]

Also: you don't have a viscous center diff in a 91. (at least, I don't think you do) so don't worry about the minor size differences.

Ahh, yes

I missed the part about it being a 91

 

[Michael Hanson]

Buy 4 keep the best old one for a spare.Whats your life worth? lt23575r15 at Sams 545.00 installed Mike

 

[WarDamnEagle]

I just had almost the same thing happen (flat followed by the recognition that the spare was a POS). I bought 5 new tires.

 

[Doc]

2 tires. drive on!

 

[jamisobe]

2 tires. Been there and done that. No problems.

I put the new ones on the front since they wear faster on the front.

 

[informationjunky]

Its a landcruiser......can you imagine what they are driven on in third world countries? Like others said...if the remaining are in good shape (tread and no dry rot), buy two new for the front.