32.8” Tyres ( 285/70R16) - 33”

[Navara 2016]

Hey Guys, I was the owner of a Nissan Safari for many years and this was my weapon of choice for “tuff wheeling”. Since I have aged, I traded this for a 2016 Navara NP300 2.4 Diesel Auto Double Turbo 4x4. Main reason for purchase is to do “ over landing” instead of “rough wheeling”.
My question is: Should I go to 33” tyres which accurately is actually 32.8” ( 285/70/16 ), will it damage my standard rear diff and standard auto gearbox?

thanks

 

[Old.Tony]

I don't think it'll do any damage, particularly as it's an auto. It will make the gearing taller, which will make the car feel more sluggish, and it will change the speedo and odometer: data for the ECU is derived from rotations of the ABS rings, so changing wheel diameter means less rotations per distance and a resulting error in the displayed distance and speed (larger wheels = lower indication than actual speed & distance).

If you're towing you might see coolant temps rise a little faster as the engine and gearbox work harder to haul everything up hills. I wouldn't tow near the car's legal limit: my own 2009 D40 (2.5L diesel) works hard up very steep inclines with our 2.5T caravan and would happily overheat if I didn't pull the gears back manually and reduce the engine load - and I have standard tyres.

 

[Navara 2016]

I don't think it'll do any damage, particularly as it's an auto. It will make the gearing taller, which will make the car feel more sluggish, and it will change the speedo and odometer: data for the ECU is derived from rotations of the ABS rings, so changing wheel diameter means less rotations per distance and a resulting error in the displayed distance and speed (larger wheels = lower indication than actual speed & distance).

If you're towing you might see coolant temps rise a little faster as the engine and gearbox work harder to haul everything up hills. I wouldn't tow near the car's legal limit: my own 2009 D40 (2.5L diesel) works hard up very steep inclines with our 2.5T caravan and would happily overheat if I didn't pull the gears back manually and reduce the engine load - and I have standard tyres.

Thats good comment, Thank you. I don’t tow, but my Ute is alway fully laden ( built up for over landing ) and I am past the age of giving it hell every time I drive it.
I will however look to find a place to recalibrate my speedo, but being New Zealand, I don’t hold much hope.

 

[Old.Tony]

Don't worry about recalibrating the speedo, just use a GPS navigation tool and monitor speed with that (it's more accurate anyway, except in tunnels, and far cheaper!). The odometer will under-read giving you a little more actual distance covered between services but it won't be so great as to kill the car.

 

[Navara 2016]

Don't worry about recalibrating the speedo, just use a GPS navigation tool and monitor speed with that (it's more accurate anyway, except in tunnels, and far cheaper!). The odometer will under-read giving you a little more actual distance covered between services but it won't be so great as to kill the car.

At 100km/h on the dash I am actually doing 108.3km/h. So it’s almost 10% out. This was calculated, not tested physically.
Would this not affect the electronics at ECU, change the “gear shift” timing etc?

 

[Old.Tony]

At 100km/h on the dash I am actually doing 108.3km/h. So it’s almost 10% out. This was calculated, not tested physically.
Would this not affect the electronics at ECU, change the “gear shift” timing etc?

Not in the least. My own car indicates speed poorly too - it's because Nissan never bothered making the needle more accurate. If you obtain the speed the ECU thinks it's doing it's actually quite accurate (my car's ECU and my GPS are rarely more than 1km/h apart). The needle is just a deflection of a coil based on the voltage sent to it. It seems to be more accurate in some cars than in others.

 

[Navara 2016]

Thanks

 

[Rainbow Warrior]

I run 265/70/17 allterrains , pull a 2ton caravan no problem at 100kph , I have a manual box , no overheating and the speedo is mor accurate.

 

[BarneyB]

Not to be pendantic, but the tyre size you are considering is actually about 31.7 inch dia.
This is almost identical to a 265/75/16...which is another popular choice & a good compromise size for do-it-all IMO.

To get close to 33" (or 32.8") you'd be looking at a 285/75/16 or 285/70/17.

I'm currently considering the same dilemma for my D40 & I have decided to keep 2 complete wheelsets, because the downsides of running 285/75/17 all day, everyday, are too much.

So I bought some cheap used rims to fit the big mud tyres for off road (Tasmania's tracks are no picnic)
And then a set of 17" alloys for 265/70/17 All Terrains for commuting & general duties.

 

[Navara 2016]

Not to be pendantic, but the tyre size you are considering is actually about 31.7 inch dia.
This is almost identical to a 265/75/16...which is another popular choice & a good compromise size for do-it-all IMO.

To get close to 33" (or 32.8") you'd be looking at a 285/75/16 or 285/70/17.

I'm currently considering the same dilemma for my D40 & I have decided to keep 2 complete wheelsets, because the downsides of running 285/75/17 all day, everyday, are too much.

So I bought some cheap used rims to fit the big mud tyres for off road (Tasmania's tracks are no picnic)
And then a set of 17" alloys for 265/70/17 All Terrains for commuting & general duties.

Mmm… no not really, the 32.8” is 285/75R16. And now that I have fitted them, they def lift the Ute by approx. 1” and look heaps better than the 265/75R16 that was on the Ute prior

 

[Navara 2016]

Not to be pendantic, but the tyre size you are considering is actually about 31.7 inch dia.
This is almost identical to a 265/75/16...which is another popular choice & a good compromise size for do-it-all IMO.

To get close to 33" (or 32.8") you'd be looking at a 285/75/16 or 285/70/17.

I'm currently considering the same dilemma for my D40 & I have decided to keep 2 complete wheelsets, because the downsides of running 285/75/17 all day, everyday, are too much.

So I bought some cheap used rims to fit the big mud tyres for off road (Tasmania's tracks are no picnic)
And then a set of 17" alloys for 265/70/17 All Terrains for commuting & general duties.

Ooops… sorry, I made a typo on my original post. The question was in fact regarding the 285/75R16, and not the **5/70R** as per my first post.