Larger Tyre Issues

[chuck]

Has anyone had any issues with fitting larger tyres to their D3 relating but not limited to the following;
1. warranty
2. traction control
3. dynamic stability control
4. fuel economy
5. fit

I am contemplating 265 x 70 x 17 - 31.6".

Thanks

Chuck

[garryc]

Has anyone had any issues with fitting larger tyres to their D3 relating but not limited to the following;
1. warranty
2. traction control
3. dynamic stability control
4. fuel economy
5. fit

I am contemplating 265 x 70 x 17 - 31.6".

Thanks

Chuck
I fitted COOPER STT's to steel 17x8" rims. They are about 14mm bigger in diameter as they are 245/70 not 235/70 as are the standard tyres. They put the fuel consumption up by 1-1.5ltrs/100km, probably because of the lumpy tread. The speedo is almost spot on with these tyres as well. I had to cut the edge off my bullbar because the STT's would rub when hitting a bump and I couldn't go to access mode. No other probs with traction or stability control but they don't handle too well on the highway so I drive more slowly through corners.:)

[lrdef110]

Have fitted Mickey Thompson 265/70/17 ATZ 4 rib. Speedo is spot on with GPS but have knocked fuel consumption around horribly. The TDV6 uses heaps more to turn these tyres around. I'm just back from doing the Simpson and rubbing on the dips has ripped a few strips out of the inner guards. Otherwise no affect on road driveability.

[TDV6]

My fuel consumption increased by more than 1L/100K when I put larger Coopers HT+ at 265/60/18 which increased tyre diameter by 9mm to 772mm.

Have a read of the car bible web site, they have lots of info on tyres which I found interesting. Car Bibles : The Wheel and Tyre Bible Page 1 of 2 (http://www.carbibles.com/tyre_bible.html)

Ryall

[Tassierob]

Have fitted Mickey Thompson 265/70/17 ATZ 4 rib. Speedo is spot on with GPS but have knocked fuel consumption around horribly. The TDV6 uses heaps more to turn these tyres around. I'm just back from doing the Simpson and rubbing on the dips has ripped a few strips out of the inner guards. Otherwise no affect on road driveability.

I would agree totally about the fuel consumption, I think about 2lt per 100 difference at least. Interesting your findings on the speedo....mine is fine up to about 80kph (you don't notice the error anyway) and after that mine reads about 97kph when the GPS indicates 100. At 100kph on the speedo the GPS is reading 105 plus so I have to be very careful not to become a revenue raising film star:(

My front tyres also rub on the chassis rails on full lock so they are nicely polished.
Typical of an agressive tread you will also notice some more noise on the road though it is not excessive.Otherwise they are an excellent all round tyre doing well on wet tarmac, mud, rock and gravel and I would definitely put another set on.:)

[Munners17]

Hi guys, first post....:)

I'm really suprised that such a small difference in size can have such a big impact on fuel consumption. Is it more to do with tread pattern?

I might be mistaken but according to the LR Australia brichure you can get 255/60 R18 tyres as standard or 255/55 R19 as standard.

Looking here Car Bibles : The Wheel and Tyre Bible Page 2 of 2 (http://www.carbibles.com/tyre_bible_pg2.html) suggests that those two sizes have about a 30mm differnce in diameter and a 5% difference in circumfrence but are still fitted to the same car with presumambly the same gearbox & diff ratios?

Seems odd to me??

Munners17

[Tote]

Re fuel consumption fitting the bullbar to my D3 made more difference to fuel economy that going to the 18"General Grabber tyres (same size as wranglers ) so I'm not convinced it's the tread pattern.

Regards,
Totes

[lrdef110]

No Munners, the ATZ 4 rib is a pretty clean tread, certainly no worse than Grabber AT2's but the TDV6 certainly makes hard work of the greater diameter. In fact it often decides to hold 5th gear instead of uploading to 6th on the highway. Manual overide can help this but around town i'm up about 3 litres per 100km. Mine is chipped so there should be plenty of power to handle the extra tyre height, just likes a drink to do it.

[TDV6]

G'day Munners,

To check tyre sizes and diameters I use Tyre Size Calculator @ ExplorOz (http://www.exploroz.com/Vehicle/Tyres/SizeCalc.aspx) where you can compare different sizes easily.

Re the 255/60 R18 and 255/55 R19 tyres, the 18's are 763.2mm and the 19's are 763.1mm in diameter which would be covered by normal variation in a set of tyres the same size.

Ryall

[Warrigal57]

Chuck

I have been running Cooper S/T 265/70 x 17 for off road trips on my D3 diesel; with another set of 255/60x18 for general use as the larger tyres are not legit in QLD (where allowable max increase on OEM is 15mm).

Re your questions:
1. warranty - my 2006 model is now out of warranty but no comment made by the Brisbane dealer at any time when I had them service the car with the larger tyres; even when there was some warranty work done on bushes wearing prematurely.
2. traction control - seems fine, never noticed any issues.
3. dynamic stability control - likewise, the car drives well and I don't notice any increased intervention by DSC.
4. fuel economy - increased by about 1-1.5L/100km but the system would be under reading slightly due to the increased rolling circumfrance of the larger tyre; so not as large an increase as recorded.
5. fit - no problems at the front with standard bumper and no rubbing on chassis as mentioned by others. Fitted a TJM steel bar and then had to cut the bar ends off to match the original as they intruded into the wheel well - no problems since, I don't think you'd have this problem with the ARB bars that I've seen.
Some rubbing at the rear under full compression in the front of the rear wheel arch - very light and hasn't caused any tyre damage. There is a panel join under the arch liner which is the problem on my vehicle (an S model) - better if this was modified to avoid the contact.
I've done a Simpson trip with a heavy load (5 people, roof rack etc) and there was very occasional rubbing but in other respects the car drove and rode very well. Completed another similar trip to the Strezlecki/Flinders ranges with less load (just my wife and I) and no rubbing at all despite many high speed miles.

As mentioned above the sealed road handling won't be as good but the vehicle still drives and handles well. Don't notice any decrease in acceleration, braking seems slightly poorer but this is in part from the extra weight being carried on trips (still stops better than my old Prado) - just keep these factors in mind.
If I was using this size all the time I would be opting for a less agressive tread in a LT for the better handling and safety on sealed roads.
There are other threads on this subject in this forum with more info. Cheers.

[Warrigal57]

Chuck

Should have mentioned I have the air suspension/terrain response fitted.

[tedndoi]

The website below was posted in an earlier tyre thread but is helpful in pointing the way to warranty and sizing issues for the D3. If running 19", Goodyear have a G4 event tyre - (MT/R) that doesnt show on the OZ website but is available @ 255/55R19S with a load index 111.

NextStepDesigns Blog Archive LR3 wheel & tire specifications and options (http://blog.nextstepdesigns.com/?p=46#comments)


regards, John

[Dingmark Jim]

I've been told by my tyre dealer that the MTR 255/55R19's are no longer available (thank goodness I have 5 nearly-new ones:D). It seems that Goodyear are making a new design MTR with aramid fibre in them with a slightly different (side-specific?) tread. The 255/55R19's don't have the aramid and are not side-specific. My tyre dealer seems to think that since neither the G4 available nor the G4 Challenge being run, then Goodyear is no longer making the tyres for the D3/D4. Should be interesting for soon-to-be D4 owners as they can't go down a rim size. I bought a set of 18" wheels and AT tyres to preserve my MTRs for the next few years.

[rmp]

Has anyone had any issues with fitting larger tyres to their D3 relating but not limited to the following;
1. warranty
2. traction control
3. dynamic stability control
4. fuel economy
5. fit

I am contemplating 265 x 70 x 17 - 31.6".

Thanks

Chuck

1. Warranty will depend on the claim in question. LR are within rights to refuse if the larger diameter was a cause.

2. Traction control is unaffected

3. Stability control is affected as the vehicle is travelling faster than the computers think it is. The question is whether it is sufficiently affected to be concerned. There is no definite answer unless you conduct some serious testing on a skidpan, but for the sort of diameter increases we're talking about for a D3 it is unlikely to be an issue.

4. Fuel economy will be affected more by construction (weight) and tread pattern. Expect to lose a little. This is often masked by other changes made at or around the same time as people fit their cars out.

5. The maximum diameter increase is somewhat limited on the D3. Not clear what can be run without rubbing, and you may not know what rubs and what does not without careful testing in all suspension modes, pushing the wheels to the bumpstops and at full lock for the fronts. I have heard of one D3 that had "no clearance issues" till it hit a bump at speed...

Consider your state's roadworthy laws too.

[Dingmark Jim]

Be careful on using web-based tyre size calculators. Last night I changed over from Cooper HT+ 265/60R18 to Goodyear MTRs 255/55R19's (going out for some mud this weekend:D). Side-by-side the two tyres are within 1mm of being the same diameter (each tyre has about 3k on it, so wear is not a factor). The internet calculator I use shows that the HT+ should be 12.1mm bigger in diameter than an MTR.

Since the MTR is original equipment for a D3, the Queenslanders may be able to argue that bigger tyres are within size spec after all.:rulez:

[rovers1952]

After I fitted Cooper S/T's, fuel consumption increased by at least 2 litres per 100 klms....urban peak period driving, but about 1 litre per 100 klms freeway/country driving. I am in no doubt that the tyres make the difference over OEM Wranglers.

[rmp]

Be careful on using web-based tyre size calculators. Last night I changed over from Cooper HT+ 265/60R18 to Goodyear MTRs 255/55R19's (going out for some mud this weekend:D). Side-by-side the two tyres are within 1mm of being the same diameter (each tyre has about 3k on it, so wear is not a factor). The internet calculator I use shows that the HT+ should be 12.1mm bigger in diameter than an MTR.

Since the MTR is original equipment for a D3, the Queenslanders may be able to argue that bigger tyres are within size spec after all.:rulez:

You can calculate the diameter of the tyre yourself quite easily.

255/55/19 =

255mm wide, 55% aspect ratio, 19" rim =

(255 * 0.55) * 2

+

(19 * 25.4)

now the actual manufactured diameter of the tyre won't be that, as it needs to account for tread depth and wear, but it'll be close enough. The inflation pressure also changes the diameter, so it's all a little arbitrary but use the above calculation for comparative purposes.

Wear at 3000km is a factor in the diameter unless original tread depth and wear rate are exactly the same, and for HT and MT that would definitely not be the case.