What tyres when new

[Gramps Advanced Member Find all posts View Profile Close Gramps]

Can anyone help??
I'm in need of some new shoes soon and am a little confused at the moment.
I have a 06 GX Ltd Turbo Diesel with current tyre size 265/70R17 on original steel rims. The handbook has 2 sizes, 225/70R17 and 265/65R17.
I know what I have is a larger size than when new, but I don't know what size were on there when new.
The speedo is out by 5kmph at the moment and fuel consumption is a little high compared to a mates GX , hence the reason for going back to original size.
If anyone can shed some light, it would be a help.

[Guest Close Guest]

On post Nov 06 GX, Toyota changed the GX rims to 17x7.5" running 265/65R17 tyres. The Standard grade came out later with the skinny rims.
Pre Nov 06, the GX rims were 17x6.0" running 225/70R17 tyres.
Since you currently have 265/70R17, then you most likely have the wider rims like the GXL and higher grades. So your best bet is to change to 265/65R17 if you wanted to go back to the standard tyre size for a 17x7.5" rim.

What are the current tyres?
With the 265/70R17, the speedo should be more accurate when compared against a GPS.
The 265/70R17 will use a bit more fuel as it is heavier and bigger diameter. It takes more fuel to turn something that is further out from the center. Because the tyre diameter is bigger, you should correct for this in the odometer before doing the fuel economy calculation. You will find that the actual fuel economy is not as bad as when you first calculated.

[mjrandom Out of control poster! Find all posts View Profile Close mjrandom]

From memory the 06 GX Limited Turbo Diesel came out with 17x7.5 steel wheels and flared guards. It was a special edition model that gained some GXL bits just before the upgrade to the D4D engine. Post November 06 GX's with the D4D kept the flares and wider wheels and tyres and the 'standard' model was introduced in place of the old spec GX with the narrower rims and 225/70 17 tyres. 265/65 17 are the correct tyres for your car. I guess you could go back to the 225/70 17 as it is mentioned on the tyre placard but you will sacrifice 14mm of ground clearance and unless you use the 17 x 6 rim which has different offset you will reduce your track which is illegal.

[Gramps Advanced Member Find all posts View Profile Close Gramps]

I know the speedo is out because I've compared it with my GPS, so I've got that one covered.
There are Bridgestone AT's on at the moment and they've been pretty good. I'm thinking more of the same or Coopers AT's. 14mm loss of ride height sounds negligible if it means the anchor is less likely to get a speeding fine.

[mjrandom Out of control poster! Find all posts View Profile Close mjrandom]

Gramps everyone else is going for bigger tyres not smaller. Are you saying that your GPS shows you doing 105kph when the speedo shows 100kph? Seems a bit odd. My experience is the other way around. I fitted 275/65 17 and the car's speedo is still reading too high, 100kph indicated is about 97kph actual but close enough. The GX Ltd would have been fitted with 265s so the speedo should be the same as mine which was about 4kph slow. With regards to tyres there are plenty of threads to look through in the 120 section depending on how agressive you want and how much off road you will be doing.

Michael

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I guess you could go back to the 225/70 17 as it is mentioned on the tyre placard but you will sacrifice 14mm of ground clearance and unless you use the 17 x 6 rim which has different offset you will reduce your track which is illegal.

Just to clarify, doesn't matter what size tyre you put on as long as the tyre is mounted on the correct rim for the Prado, it will not affect the track. The vehicle track is dependent only on the rim offset.

[Way2go Member Find all posts View Profile Close Way2go]

With the 265/70R17, the speedo should be more accurate when compared against a GPS.

My experience has been the opposite, and I've only gone to 275/65R17s (same as Michaels' experience above)

My speedo was pretty much spot on with the 265/65s, but now it reads low - when travelling at 110 (GPS) the speedo reads about 106, at 100 it reads 97, etc. right down to 60 when it is reading about 58/59.

(Very useful to know, especially when there is a double demerits weekend!)

[Guest Close Guest]

Spot on, mine with Bridgestone D694's 265/65/17 shows perfect speed to GPS and speed checks.
With My MTZ 265/70/17 110 on speedo was infact 114 true kmh by gps & speed check.

Larger diameter = more error the wrong way..

With the factory Grandtreks it was low, 111 indicated was actually 107 kmh.

As I have said in another thread, going back to 265/65 from the 265/70 the following applied: more accurate speedo reading / better braking / 1.9 litres fuel LESS used per 100 kms / Bumpier ride with smaller size. (less sidewall)

[Guest Close Guest]

The speedo accuracy depends on the year model. Sometime around 04 & 05, the speedo started to under read instead of being spot on.

[OldGreyGuy Senior Member Find all posts View Profile Close OldGreyGuy]

The speedo accuracy depends on the year model. Sometime around 04 & 05, the speedo started to under read instead of being spot on.

I can agree with that my 2008 model was reading 95 or so on the GPS when the speedo was reading 100, the confirmation was the fact that people were always passing me on the highway when I had her sitting on 100, even through the speed camera at Burpengary.

Put on 275/65s and the GPS and speedo now are very close, and I am keeping up with the traffic.

[mortrod Lurker Find all posts View Profile Close mortrod]

Hi Gramps
I have a 2004 VX Diesel with the standard 265/65R17, and will been looking for new tyres towards the end of the year.
A couple of mates of mine have now changed over to Mickey Thompson Baja Radial ATZ plus and they have been raving about these tyres
one set is on a F250 twin cab and the other is on a new 70 series Landcruiser wagon. they have gotten the correct size for there trucks.
Unfortunately they only make a 265/70R17 to suite the Prado, now as it turns out i was driving with my work the other day and happened
across a chape that had this same tyre on his Prado. He told me that this was the only size also(265/70R17), but he was more than happy with them.
He had only had them on for three weeks and loved them, he said they were quite and felt great on the road, he said it has put the speedo out a touch
but he did not worry about it. He also said he thought he was getting better fuel economy but had not done any tests.
Anyway this is what i will be putting on Gramps, They looked cool to..... hope this helps a bit
Roddy

[tassie tiger Advanced Member Find all posts View Profile Close tassie tiger]

Hi Gramps

I have the same diesel as yours with the 4 spd auto. I went from the std 265/65 to the slightly taller 265/70 using goodyear silent armours. Fuel use went up by a minimum of .5lphk but what was annoying is that the gearing was out a bit and the vehicle felt underpowered around the 80k mark. Like it had changed up gears too early and out of the 'power band'. It is now exactly 3k's out at 100kmh onthe gps.

I will be going back to std when these wear out - if they ever do!

[Schaffer Addicted PP Member Find all posts View Profile Close Schaffer]

Hi Gramps
I have a 2004 VX Diesel with the standard 265/65R17, and will been looking for new tyres towards the end of the year.
A couple of mates of mine have now changed over to Mickey Thompson Baja Radial ATZ plus and they have been raving about these tyres
one set is on a F250 twin cab and the other is on a new 70 series Landcruiser wagon. they have gotten the correct size for there trucks.
Unfortunately they only make a 265/70R17 to suite the Prado, now as it turns out i was driving with my work the other day and happened
across a chape that had this same tyre on his Prado. He told me that this was the only size also(265/70R17), but he was more than happy with them.
He had only had them on for three weeks and loved them, he said they were quite and felt great on the road, he said it has put the speedo out a touch
but he did not worry about it. He also said he thought he was getting better fuel economy but had not done any tests.
Anyway this is what i will be putting on Gramps, They looked cool to..... hope this helps a bit
Roddy

I would hardly think that putting a larger heavier tyre on any vehicle will improve fuel economy.

The ATZs are a great tyre but like ALL tyres you need to treat them according to the conditions you are driving otherwise you will end up with tyre dfamage and then we will probably see another post from someone complaining that tyre X is crap because "they" didn't apply the rules of off road driving which is to reduce tyre pressure and spped to suit the terrain.

[Schaffer Addicted PP Member Find all posts View Profile Close Schaffer]

The speedo accuracy depends on the year model. Sometime around 04 & 05, the speedo started to under read instead of being spot on.

I think youy also need to split this for Petrol and Diesel. There was an update on the petrol changing from 4 speed to 5 speed on the auto about 18months or more before the diesel (which occued in Nov 2006 with the release of the D4D). I have a 2006 Auto TD April build and with 265/70s my speed is out by about 3kms at 110km/h according to the GPS.

[PradOz Advanced Member Find all posts View Profile Close PradOz]

i spoke with my local tyre dealer this morning for a quote. here is what they said:

standard size is 265/65 R17

in coopers (all available)

ATR 265/65 $295 each with 60,000 km wty

AT3 265/65 $335 each with 80,000 km wty [these are ATR replacement yet both are still available]

ST 265/70 $355 each with 60,000 km wty. the speedo will be out with these. speedo=100, actual speed= 103 [depending on your pressures etc]

If you want to go back to standard go the AT3 and you should be ok. The AT3 is suppose to 'fix' some of the issues with the ATR some have raised about chipping etc, but in 2 sets of ATRs i havent had the problem. the standard Dunlop Grand Trek AT20 that is on my car is 265/65 R17

cheers mick