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malsgoing130
7th September 2009, 12:32 PM
I am about to replace the 130's tires and wanted to go to 255/85 16 which seems to be the right option, but right now i have 265/75 16 and wanted to use the 2 good ones as spares. Logic tells you that the width is the big issue. By this what i mean is if you have to put the spare on that axel would mean that you have tires of differing dimensions, would this do damage? i know that on trucks you should not do it, is it the same on fenders?
Thanks
mal

wisey110
26th September 2009, 07:02 AM
You'll end up putting huge stress on your drivetrain. the smaller tyre will drag. old man had to drive around in a freelander because disc was getting fixed the rear tyres were screaming couldn't figure out why until he looked at the sizes.

spudboy
26th September 2009, 10:51 AM
That;s a fair bit of difference. Here's some stats:

Tyre 1 - 265/75R16 >Tyre 2 - 285/85R16
Section Width:10.43 in 265 mm Section Width:11.22 in285 mm
Overall Diameter:--Overall Diameter:31.64 in803.65 mm Overall Diameter:35.07 in890.77 mm
Sidewall Height:--Sidewall Height:7.82 in198.62 mm Sidewall Height:9.53 in242.06 mm
Radius:--Radius:15.82 in401.82 mm Radius:17.53 in445.26 mm
Circumference:--Circumference:99.39 in2524.5 mm Circumference:110.1 in2796.5 mm
Revs per Mile:-Revs per Mile:657.3 Revs per Mile:593.0

Hmmm - the formatting didn't copy nicely :( Go here to see in the proper format: http://www.1010tires.com/tiresizecalculator.asp

Lotz-A-Landies
26th September 2009, 11:06 AM
I am about to replace the 130's tires and wanted to go to 255/85 16 which seems to be the right option, but right now i have 265/75 16 ...
That;s a fair bit of difference. Here's some stats:

Tyre 1 - 265/75R16 > Tyre 2 - 285/85R16 Unfortunately the sizes compared weren't the same as the original post:

Tyre Difference Comparision (http://www.exploroz.com/Vehicle/Tyres/SizeCalc.aspx)
Select Wheel/Tyre 1 / R 255/85 R16
Select Wheel/Tyre 2 / R 265/75 R16

Results for your selected Wheel/Tyre 1
Rolling Radius 419.95mm
Circumference 2638.62mm
Diameter 839.9mm
Wheel Cover Size Size 009

Results for your selected Wheel/Tyre 2
Rolling Radius 401.95mm
Circumference 2525.53mm
Diameter 803.9mm
Wheel Cover Size Size 009

Differences between Wheel/Tyre 1 & 2
Rolling Radius -18mm
Circumference -113.09mm
Diameter -36mm
When your speedo reads 100km/hr you're actually at 95.52 km/hr

spudboy
26th September 2009, 02:08 PM
Unfortunately the sizes compared weren't the same as the original post:



Oh - bugger -sorry about that. Short term memory is getting worse the older I get :mad:


Anyway - hope Diana's corrected figures are useful....

buzz66
26th September 2009, 02:59 PM
You'll end up putting huge stress on your drivetrain. the smaller tyre will drag. old man had to drive around in a freelander because disc was getting fixed the rear tyres were screaming couldn't figure out why until he looked at the sizes.

Not quite true. Even at 100 KPH the different tyre sizes will cause the rear diff hemisphere rotation of 1.07 revolutions per second. This is not enough to cause inadequate lubrication of the hemisphere shafts, planet, spider gears. The centre diff will be even less worked.

It will test the limits of the V.C. type transfer case used in 89 and later Rangy's.

As for a freelander I am not familar with its drivetrain.