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I need new tyres in the next 5000kms.
Since I bought the car in July 2011, I've put on 5000kms.

I'm choosing between

1) 185/75R-14, comes in passenger style.
2) 195/70R-14, also passenger style
3) 185R14, light truck tyre

Advantages of each? (my guesses; tell me if I'm wrong)

1. Maybe better economy, hopefully less load on steering, bearings etc. than others
2. Looks great, better cornering, braking, perhaps vaugely better aired down? Lighter than 185R14.
3. Vaugely better highway economy and acceleration than 195's? LT means more sidewall protection.

I think all will fit without me modifying the back of the fron wheel wells.

Anyone want to suggest brands and tread styles, it will be welcome.

the light truck tyres are over the top in my opinion.
they wont be nearly as good on the road. a road tyre will still be far better on sand. the only benefit i can see is that will have a slighlty lower chance of ripping sidewalls etc if you are rock crawling.

I think, Light truck would be a very heavy tyre.

I've only got road tyres, so far so good and way better in sand, get a second set of rims and go see a rally team and get a set of their old tyres if you are going bush, I'll be doing that when I get back, you'll get them for next to nothing.

d_generate wrote:I've only got road tyres

And look where I got - see sig pic

How wide are the rims you intend to use with these tyre choices - width is determining a few things. LT - yeah, would think they are too heavy and too tall a profile to feel safe

I've got 185/70R-14's right now:

185/75R-14's are 9mm taller radius
195/70R-14's are 7mm taller radius
185R-14's are 10-17mm taller radius (a bit vauge on diameter imho)

LT tyres aren't more aggressive tread, just stiffer sidewall.
If it's overkill, I'm happy to just use lighter passenger car tyres.

I'd go for the LT tyres. Alot of the tracks heading to the sand are rocky and limestoney. I've popped afew sidewalls on regular road tyres, surprise surprise this ceases to happen when tougher tyres are installed.

Sent from my HTC Desire using Tapatalk

can subaru,s go anywhere extreme enough to need LT ahah... personally id go Lt but they all have their pros and cons

steptoe wrote:And look where I got - see sig pic

Ahh, but if you look properly you'll notice the sand was extremely soft and the tyres bulldozed the sand out of the way until the car was sitting on it's belly, they didn't spin and dig in, they went till there was virtually air under them ....... so ehhhhhhhh

steptoe wrote:And look where I got - see sig pic

d_generate wrote:Ahh, but if you look properly you'll notice the sand was extremely soft and the tyres bulldozed the sand out of the way until the car was sitting on it's belly, they didn't spin and dig in, they went till there was virtually air under them ....... so ehhhhhhhh

So its the SANDS fault then
hahaha...thats your story & you're stickin to it lol

2nd Hand, my opinion is keep away from LTs unless you have a light truck!
I kno it doesnt rain much there in the sunny (desert) state but when it does they wont be much fun. Plus they wont handle anywhere near as well or be as comfortable as a passenger car tyre.
The only thing is Alex's point...but if you're careful & dont go sideways lol you should be fine.

Depending on how much heavier those LT's are you might take a bit of a hit to both performance and economy. Its more than just how big they are and rolling diameter (and hence your gearing), there's rotating mass to take into account too.

To answer the title question, yes, passenger tyres will be fine for occasional aired-down use. LTs would just be less likely to suffer damage.

That LT designation describes construction of the tyre - number and type of plies and characteristics of the rubber compound. Traction is a function of rubber composition and tread pattern - so a general statement that LT tyres won't grip is horseshit.

Yes, LTs are heavier - that's what makes them LTs. Take some scales to your tyre shop if it's a major concern; I'd be interested to see what you find.

Dane.

I understand what you're saying but surely they dont put grippy compounds in TRUCK tyres...you dont see too many ferraris or lambos with LTs lol

they arent really truck tyres when they say LT.

the much chased after 27inch nankang supertrippers are LT tyres.

Dane hit the nail on the head. I think for a semi offroad tyre, LT is absolutely ideal.

The pros far outweigh the cons. I wouldnt be suprised if theres fark all difference between the mass of a LT vs passenger tyre.

Like i said, i always ran LT tyres on my l-series and they were fine. (its not like a lifted l-series can handle anyways)

if its that much of a hassle why dont you get a set of LT carcasses and throw a set of bandag,s of your choice on them

Dredging up the weight issue for anyone who's interested:

-3/4 worn Sumitomo 185R14 LT mounted on a desert rat = 19kg
-bald 27" Super Tripper on a desert rat = 20kg
-half worn 175/65R14 on a different steel wheel (trailer) = 15kg
-a half worn 31" Cooper ST on a 16" alloy is 30kg (and I have to lift it higher to put it away!).

Got some scales today, so I've been having fun weighing stuff.

Dane.

GOD wrote:Dredging up the weight issue for anyone who's interested:

-3/4 worn Sumitomo 185R14 LT mounted on a desert rat = 19kg
-bald 27" Super Tripper on a desert rat = 20kg
-half worn 175/65R14 on a different steel wheel (trailer) = 15kg
-a half worn 31" Cooper ST on a 16" alloy is 30kg (and I have to lift it higher to put it away!).

Got some scales today, so I've been having fun weighing stuff.

Dane.

Thanks

I have Sumitomo 185/70R-14's on Sunraysias, little tread @ 18kg
I also have an oversize spare at 195/70R14, big tread on a Sunraysia and it's 21 kg.
(I think I remembered that right)

I think I'll stick to my 16" alloys with cheap street tyres then, roughly 16kg all up.

Something interesting.
Simply put, sprung weight is everything from the springs up, and unsprung weight is everything from the springs down. Wheels, shock absorbers, springs, knuckle joints and tyres contribute to the unsprung weight. The car, engine, fluids, you, your passenger, the kids, the bags of candy and the portable Playstation all contribute to the sprung weight. Reducing unsprung weight is the key to increasing performance of the car. If you can make the wheels, tyres and swingarms lighter, then the suspension will spend more time compensating for bumps in the road, and less time compensating for the mass of the wheels etc.
The greater the unsprung weight, the greater the inertia of the suspension, which will be unable to respond as quickly to rapid changes in the road surface.
As an added benefit, putting lighter wheels on the car can increase your engine's apparent power. Why? Well the engine has to turn the gearbox and driveshafts, and at the end of that, the wheels and tyres. Heavier wheels and tyres require more torque to get turning, which saps engine power. Lighter wheels and tyres allow more of the engine's torque to go into getting you going than spinning the wheels. That's why sports cars have carbon fibre driveshafts and ultra light alloy wheels.

Read more: http://www.carbibles.com/suspension_bib ... z1d2DmiEFx

d_generate wrote:I think I'll stick to my 16" alloys with cheap street tyres then, roughly 16kg all up.

Something interesting.
Simply put, sprung weight is everything from the springs up, and unsprung weight is everything from the springs down. Wheels, shock absorbers, springs, knuckle joints and tyres contribute to the unsprung weight. The car, engine, fluids, you, your passenger, the kids, the bags of candy and the portable Playstation all contribute to the sprung weight. Reducing unsprung weight is the key to increasing performance of the car. If you can make the wheels, tyres and swingarms lighter, then the suspension will spend more time compensating for bumps in the road, and less time compensating for the mass of the wheels etc.
The greater the unsprung weight, the greater the inertia of the suspension, which will be unable to respond as quickly to rapid changes in the road surface.
As an added benefit, putting lighter wheels on the car can increase your engine's apparent power. Why? Well the engine has to turn the gearbox and driveshafts, and at the end of that, the wheels and tyres. Heavier wheels and tyres require more torque to get turning, which saps engine power. Lighter wheels and tyres allow more of the engine's torque to go into getting you going than spinning the wheels. That's why sports cars have carbon fibre driveshafts and ultra light alloy wheels.

Read more: http://www.carbibles.com/suspension_bib ... z1d2DmiEFx

Dont forget lightened flywheels. Not sure if race cars have steel or alloy but they will be billet & ultralight

Its also why AWD saps more power than 2WD.
Last I heard 2WD sapped approx 1/3 of the engines power, ie, 300HP at the flywheel equates approx to 200HP at the wheels.
Not sure what AWD is but would be fair bit less than that due to 2 extra diffs, etc.

i remember reading once that lightened flywheels are a big no-no for 4wds as heavier creates more momentum and is far better in sand.