tyre aspect ratio affect non AWD 4WD box diff bind?

steptoe · Post by **steptoe** » Tue Apr 12, 2011 11:30 pm

Just wondering if anyone experienced same as me with L Series and MY part time 4WD boxes and low profile tyres, and diff binding.

Running 195/50 15"s and getting diff bind causing need to thump back into FWD on dirt roads and wet tarmacadam (that's what I believe its full name is!)

Was not doing it on my 185/60 14"s all of which were same tyre, the 15's however have a ring in or two....two different generations of Roadstones on the back, BJ Zenon 1's? on the front.

Could just be that the different brands and gens of tyres even though same size may have different rolling circumferences (actual not theoretical) causing this or is it that a 50 series tyre has less squishy give?

I am waiting for drive and time to fit new BJ257 ball joints, a nice tight rack end before fitting some new Bob Jane Zenon X7's (some of the last made in Adelaide before they went off shore) and a front wheel alignment before I will know if it is tyres brands and wear rate than ratio

RSR 555 · Post by **RSR 555** » Wed Apr 13, 2011 12:16 am

Different brands have different rolling diameters even when claiming to have the same tyre sizes. I've seen many Outbacks and WRXs that have blown centre diffs due to this same issue. This usually happens after long drives.

littlewhiteute · Post by **littlewhiteute** » Wed Apr 13, 2011 5:59 am

RSR 555 wrote:Different brands have different rolling diameters even when claiming to have the same tyre sizes. I've seen many Outbacks and WRXs that have blown centre diffs due to this same issue. This usually happens after long drives.

Yes, that exactly right. DO NOT run different brand tyres on any 4WD or AWD vehicle.

steptoe · Post by **steptoe** » Wed Apr 13, 2011 10:07 am

I have in the past seen two different brands of same size with a total height difference of about 10mm - yeah , so aware of this, was wondering if anyone experience the low profile thing