Thread: Talk to me about Tyres & Towing

Originally Posted by Fluids

Anyone care to answer this one ?

Yes, std tyres give me around 2275 rpm at 100 kmh whilst 265/75's give me a fraction over 2000 rpm at the same speed.

Hi Franz. By my GPS with 255/70 (approx' rpm's)

80kmhr - 1800rpm
90kmhr - 2050rpm
100kmhr - 2250rpm

So 90kmhr (by GPS) with the 265/70 should drop to around 2000rpm.

New tyres being fitted today.

Originally Posted by Fluids

Hi Franz. By my GPS with 255/70 (approx' rpm's)

80kmhr - 1800rpm
90kmhr - 2050rpm
100kmhr - 2250rpm

So 90kmhr (by GPS) with the 265/70 should drop to around 2000rpm.

New tyres being fitted today.

Hi Fluids,


Yes, that's about what I get with my 255's and my 265/75's. My readings are from a Nanocom.


Cheers,


Franz

Tyres are on. Did a round trip of around 70 km.

90kmhr - 1975rpm
At 90 the speedo reads about 83/84kmhr. At this speed boost used to be around 0.55-0.58bar, it's now around 0.64-0.66bar
I filled up when I picked it up so we'll see how the mileage fares

Tires are 210mm wide shoulder to shoulder ... The 255 Coopers are 215mm !?
Tyres are definitely heavier than the Coopers (LT vs Passenger)

They sit real close to the front inner guard when turned ... But no rubbing on lock to lock (no flexing)
The ride is definitely a bit stiffer (though the fitter has the tyres at 40psi all round - old tyres were 33Fr/38Rr

Can definitely notice the reduced performance, it's minor, but a little more loud pedal and it gets along, dare I say, better than it used to!
Legs are stretched a little in 3rd lockup (good for towing), and each gear change is maybe 2-3kmhr later. It's does mean that 4th lockup happens at around 82 on the speedo which is nearly 90 actual, then dropping back to 80 actual has the speedo sitting at 74/75 ... _just_ above unlock.

Tow hitch sits 20mm higher ??? Don't know how that happens, but I needed a higher height for the camper Cool.

So far I'm pleased with the result. See how we fare on the trip to Wollongong next week and the return trip home with the camper trailer in tow. Can't wait !

Thanks for everyone's input and assistance. I'll update the post next week.

Sent from my iPad using Braille

Kev, I'm 20 minutes up the road from Wollongong, if you need any help, or just want to catch up for a beer, just PM me

Baz.

Thanks Baz ! Will keep that I'm mind.

Oh, and btw ... The spare JUST drags on the rear bar ... No gap visible ... See how we go fitting the new AULRO wheel cover (which I ordered as a 255/70) tomorrow.

Sent from my iPad using Braille

Mt. Ousley (or Bulli Pass) will be a good test!

My td5 is a manual and would pull Ousley in top gear @90-100k's on 255/65's with standard tune, now on 265/75's with a TRS chip it's back to 4th, so I'm currently trying to suss out a re-gear as it's pretty high when towing (I'm talking 3 tonnes).

I'd say the difference between 70's and 75's would be negligible, and both would affect towing performance substantially. Probably less so on slush boxes than manuals though!

Cheers
Will

Originally Posted by Fluids

Thanks Baz ! Will keep that I'm mind.

Oh, and btw ... The spare JUST drags on the rear bar ... No gap visible ... See how we go fitting the new AULRO wheel cover (which I ordered as a 255/70) tomorrow.

Sent from my iPad using Braille

Looks like you'll need to flip the tyre mount, it's an easy job, 30 minutes tops.

As for the cover, you might be lucky, PM Dave, he might be able to help.

Baz.