- Thread starter
- #41
Well duh! Would you buy a $50K vehicle that didn't?
Besides, I don't think we've hashed this subject out enough quite yet.
Mismatched small spare tire on an 80. Effects?
- Thread starter BrettinSanAntonio
- Start date
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Well duh! Would you buy a $50K vehicle that didn't?
Besides, I don't think we've hashed this subject out enough quite yet.
I can't even begin to imagine why anyone would ever even think of altering anything on an 80 to be different from the way it was originally sold. Toyota did everything the way they did for a reason so why change any of it?
Why step out of the box when you can lay down and fall asleep in it?
- Thread starter
- #43
I can't even begin to imagine why anyone would ever even think of altering anything on an 80 to be different from the way it was originally sold. Toyota did everything the way they did for a reason so why change any of it?
Why step out of the box when you can lay down and fall asleep in it?
Exactly! All those pesky rock sliders, suspension systems, roof racks, swing out carriers, lights, bull bars, L.E.D.'s, radios, engine mods, superchargers, skid plates, oversized tires, etc., etc. are ridicules. We should leave our rigs alone just like they came from the factory.
Thanks for helping me with the tire lift mod. It's looks perfect for the 31. It really pulls the spare out of harms way. I'm going to look at squeezing that 33 in there deflated and see what I think.
- Thread starter
- #44
No, no, no. We're on the same page here and I hear what you're saying. I'm just searching for an alternative that may exist. If I can't achieve the desired result in a safe and effective manner, I'll go back to something proven and I'll post the results. If I can't make it work, perhaps another cruiserhead can find a solution in a future attempt.
And thank you. I take pride in my "weird criteria".
And thank you. I take pride in my "weird criteria".
Ah that's right I forgot about the whole wife situation.
My recommendation to the issue at hand is that it would be acceptable but not idealy desirable. First issue is if the tire that needed to replace was a front tire. You would need to rotate a good rear tire to the front and put the spare then on the rear.
To avoid overheating and humping (yes it's technically called this) of the viscous coupler you would need to lock the CDL. Worst case for the viscous coupler would be that it no longer would act like a "limited slip" but a fully locked differential. Locking the CDL would of course fully advoid this.
Finally the side gears and spider gears in the rear carrier where never desinged to maintain a constant speed differential. Worst case here is carrier and side gear wear. Hard to say how it would manifest its self, but I would say excessive backlash on the spider gears could open the door to breakage. The lockers work in such a way that stress is transfered through the side gears and spider gears when engaged. Excessive backlash on the side/spider gears may be fine when the diff is open but it could break under hard strain when locked.
So how far could you drive without putting wear on the side gears/carrier. Hard to say but I would avoid highway speeds for sure and the shorter the distance the better.
My recommendation to the issue at hand is that it would be acceptable but not idealy desirable. First issue is if the tire that needed to replace was a front tire. You would need to rotate a good rear tire to the front and put the spare then on the rear.
To avoid overheating and humping (yes it's technically called this) of the viscous coupler you would need to lock the CDL. Worst case for the viscous coupler would be that it no longer would act like a "limited slip" but a fully locked differential. Locking the CDL would of course fully advoid this.
Finally the side gears and spider gears in the rear carrier where never desinged to maintain a constant speed differential. Worst case here is carrier and side gear wear. Hard to say how it would manifest its self, but I would say excessive backlash on the spider gears could open the door to breakage. The lockers work in such a way that stress is transfered through the side gears and spider gears when engaged. Excessive backlash on the side/spider gears may be fine when the diff is open but it could break under hard strain when locked.
So how far could you drive without putting wear on the side gears/carrier. Hard to say but I would avoid highway speeds for sure and the shorter the distance the better.
- Thread starter
- #46
Yep. She's loving the new look and I've gotta say, I really like walking right up to the back of the truck and opening the hatch without having to swing a tire out of the way.
It's all going to be fine. Relax. Take time to stop and smell the roses...or the burning Viscous.
It's all going to be fine. Relax. Take time to stop and smell the roses...or the burning Viscous.
Ah that's right I forgot about the whole wife situation.
My recommendation to the issue at hand is that it would be acceptable but not idealy desirable. First issue is if the tire that needed to replace was a front tire. You would need to rotate a good rear tire to the front and put the spare then on the rear.
To avoid overheating and humping (yes it's technically called this) of the viscous coupler you would need to lock the CDL. Worst case for the viscous coupler would be that it no longer would act like a "limited slip" but a fully locked differential. Locking the CDL would of course fully advoid this.
Finally the side gears and spider gears in the rear carrier where never desinged to maintain a constant speed differential. Worst case here is carrier and side gear wear. Hard to say how it would manifest its self, but I would say excessive backlash on the spider gears could open the door to breakage. The lockers work ins such a way that stress is transfered through the side gears and spider gears when engaged. Excessive backlash on the side/spider gears may be fine when the diff is open but it could break under hard strain when locked.
So how far could you drive without putting wear on the side gears/carrier. Hard to say but I would avoid highway speeds for sure and the shorter the distance the better.
I just wanted to break it down for you. Honestly how many times have you used the spare and how far from a tire shop have you been in the past. I'd say the odds are that you're probably fine. If I'm not mistaken hasn't there been a few trips on a flat bed??
What I don't get is the 31" tire fitting better than a 33"?? Isn't the main issue under there the width of the tire?? I'm sure they make a skinny 33x9.50-16, which is then narrower than the stock 31" tire (I assume that is the 31" tire you're talking about).
What I don't get is the 31" tire fitting better than a 33"?? Isn't the main issue under there the width of the tire?? I'm sure they make a skinny 33x9.50-16, which is then narrower than the stock 31" tire (I assume that is the 31" tire you're talking about).
Toolbagness attained.
You guys are right. Thanks for setting me straight, Pair_of_Eees, Grench and Beowulf.
I like to quickly check 'Mud while at work for a little mental vacation; perhaps I should slow down and think a bit before typing.
Sorry to steer the thread in a pointless direction.
I had a flat recently while I was working Ike in Port Arthur. I was fortunate that it happened about a half mile away from the only open tire shop in the entire tri-city area (Thank you GPS). I drove there on the flat, but the tire was repaired with no problems.I just wanted to break it down for you. Honestly how many times have you used the spare and how far from a tire shop have you been in the past. I'd say the odds are that you're probably fine. If I'm not mistaken hasn't there been a few trips on a flat bed??
What I don't get is the 31" tire fitting better than a 33"?? Isn't the main issue under there the width of the tire?? I'm sure they make a skinny 33x9.50-16, which is then narrower than the stock 31" tire (I assume that is the 31" tire you're talking about).
The 33 will not fit underneath with the Kaymar due to the beefy support present for the tow bracing. 31 is the max, ...inflated
.
And thank you. I take pride in my "weird criteria".
No problem. My sliders are classic "weird criteria" but they've worked OK for me for 7 years. (Need some tweaking though...)
On the deflated tyre idea that Grench proposed... Use a ratchet strap to pull the center of the tyre into the rim like one of those temporary doughnuts they used to put in cheap cars back in the 70s. You might end up with enough room under there for 2 of them.
Is your wife going to be able to deal with a rush hour flat? (Rhetorical question... no reply necessary.)
-B-
Here's a thought: Keep a 31'' underneath for in town. You'll always be close to a tire shop. When you plan to travel farther than 50 miles from a tire shop, strap your 33'' on top. Too bad you didn't get a bumper with spindles, you could throw them on in the morning and deal with the hassle of the swing out for a weekend.
My PO did this. I've still got the 275/70R16s on the front and 265/75R16s on the back. So that's a 0.492" diameter difference and a 1.54" circumference difference between front and back. Obviously a lesser extreme than the 31" vs 33" but how bad was/is it for the VC? Anyone know of people who've screwed up theirs with 1/2" diameter difference?
There is a good technical description in the NCF (New Car Features) manual for the 1996 LX450. You should read that to gain an understanding of what your VC is doing. This theory of operation of the VC has been posted several times. "How bad was/is it for the VC?" Well, you can leave it like that and let us know or you can assume the Toyota engineers had a reason for specifying same size tyres and change yours before it fails. Has the damage already been done? Dunno... you would have to let us know if you think your VC is locking up prematurely. There is no way for anyone to give you a definitive answer though some may make a guess.
Dan bought a used truck with a locked up VC. No prior history on the truck so no way to say how long it was run with different sized tyres or even if that was what caused the VC failure. However, it can be removed with no major issues. The center diff will not function as a limited-slip but, other than that and a potential impact on ABS operation, you can run without the viscous coupler.
-B-
Dan bought a used truck with a locked up VC. No prior history on the truck so no way to say how long it was run with different sized tyres or even if that was what caused the VC failure. However, it can be removed with no major issues. The center diff will not function as a limited-slip but, other than that and a potential impact on ABS operation, you can run without the viscous coupler.
-B-
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No way for us to know how many miles the PO drove with that set up, but out of curiosity how many miles have you put on your truck since you have owned it? If your VC was locked I would suspect that your truck would do some hopping around corners. Doing any hopping?
I am sure it would be a good idea to get 4 tires that are equal in size asap.
Enough to be embarrassed in the context of this thread (about 3000 miles). I suspect/hope the PO might've put the mismatched tires on to sell it.
Not yet.
Hopefully this Xmas will allow that. It's not a daily driver so it can sit around most of the time while I save up for new shoes.
I just wanted to break it down for you. Honestly how many times have you used the spare and how far from a tire shop have you been in the past. I'd say the odds are that you're probably fine. If I'm not mistaken hasn't there been a few trips on a flat bed??
What I don't get is the 31" tire fitting better than a 33"?? Isn't the main issue under there the width of the tire?? I'm sure they make a skinny 33x9.50-16, which is then narrower than the stock 31" tire (I assume that is the 31" tire you're talking about).
Eyeballing mine, I would have had to let out enough air for the tire to indent about an 1.5 to 2" Otherwise it would still rub on the panhard bar. Side-to-Side is no problem, and neither is the "width" of the tire after doing the spare tire mod.
----------BrettinSanAntonio--------------
So have you tried deflating it? I thought about this when I ran into the same problem you are having. 285 underneath w/Kaymar doesn't fit. I went the route of an interior tire carrier. But I'd like to know if you try the deflating, how much you had to deflate to. If so, I'd at least know I have that option
and maybe even 2 spares.I decided against this because I didn't want to damage a brand new tire. I'm not sure if it would or not, but I still had the option of using the interior.
I figured, it wouldn't get used much, but always be in the compressed state.
Besides leaving a flat spot that would take a little driving to round out, would being folded lead to premature cracks in the rubber?
- Thread starter
- #57
Not to get too far off topic but the spare time mod is freaking brilliant and I'm very pleased with mine. It makes a huge difference.
I didn't bother to read all the posts, so flame me if need be.
If you can't afford a real size spare to match your 33's, I doubt you'll be able to afford the work to fix any possible damage caused by running a tire 3" smaller than the others. I know there is more "tech" to a 80 than a AWD Subaru/Audi, etc, but on those cars, running different sized tires can fry the axle diff/viscous coupler, so I don't see why we can't resonably assume that where possible, we should try to treat our 80s with the same level of care (bombproof nature of the 80 aside).
It is ridiculous to go out with a temporary solution that might cause your rig serious harm.
My recommendation? Call around to tire shops and find a used 33" tire that will fit on your rim. Set your budget at $80 (or $40) and just do it. I think the peace of mind here is worth it.
If you can't afford a real size spare to match your 33's, I doubt you'll be able to afford the work to fix any possible damage caused by running a tire 3" smaller than the others. I know there is more "tech" to a 80 than a AWD Subaru/Audi, etc, but on those cars, running different sized tires can fry the axle diff/viscous coupler, so I don't see why we can't resonably assume that where possible, we should try to treat our 80s with the same level of care (bombproof nature of the 80 aside).
It is ridiculous to go out with a temporary solution that might cause your rig serious harm.
My recommendation? Call around to tire shops and find a used 33" tire that will fit on your rim. Set your budget at $80 (or $40) and just do it. I think the peace of mind here is worth it.
I was in the same predicament and drove 250 miles with no ill effects. 3 33" tires and 1 31" tire in the rear. I locked the CDL, drove wisely (but still at 70+), and didn't have any issues. That happened 2-3 more times, I always swapped the smaller tire, and never had a problem.
Money isn't the issue for him, it's the physical size of the spare 33" tire.
