Big tyres

Your speedo is out by lots

your gearing is shot you will be doing 100kph at around 1rpm

Its illegal in most states, or you need to get your car reengineered at a cost of $$$100's.

Cost of tires

You need different flairs to be legal

you need a lift kit to clear them or hit your guards with angle grinder.

theres a few..

Dave,
Spot on re speedo being out. You will find a reduction in power, probably ending up using more fuel in the long run, to get the beast rolling. Your top gear may not be the right ratio to let the engine give you best performance.
The cost of having the speedometer recalibrated...
The fines from the Highway Patrol should they report you for the vehicle not complying with the standards....goes on and on.
Re-registration? Try to run your vehicle over the RTA pits and see the attention given by the inspectors......on and on and on.....
Must admit though, the 35's may look good but I'd hate to experience the change of the centre of gravity......an interesting thought.
Finally, out in the bush away from it all and experiencing a staked tyre. There goes the spare. Another flat and try to buy a 35" tyre 'outback'. Don't like your chances in getting one.
Good luck,
Haldo

Hi Dave,
I guess it all depends on what you are trying to achieve. I have a troop carrier and went from 31s to 35 in one hit.

Negatives where:
Speedo went out.....but callibrated with gps so know 52 is 60 etc
Bump Stops and Guard Clearance...had to fit flares and create new bump stops
to stop the tyres hitting the top of guard
Increased Bump Steer.....replaced steering dampener with heavier unit
Heavier Steering.......had to fit wedges behind axle to help the power steer
replace tyres...have had one unrepairable stake..cost to replace one $350

Positives are:
Better clearance and approach and departure angles
Much better traction...larger tyres improve tread depth
Better overall ride...dont have larger tyres inflated as hard
Looks.....might be vain but eh i love it
Overall better footprint in off road situation

It may be true that you will suffer in the power stakes, but for me i turned up the boost on the turbo from 7 psi to 10 psi and it has made neglegable difference. Having said that you do notice that your low range is not quite as low....but it then comes down to what sort of low range you had to start with...the troopy was great to start with...and with the twin lockers its damn near unstoppable!!!
IN the end i think it comes down to needs vs wants and driving the cheapest thing your ego will let you get away with..............oh hell that sounds like something my wife would say!!!!!!!!

cheers
tastroopy

DaviiiMQ.

There are far more negatives than positives running oversize tyres.
Despite the popular belief you don't get more traction.
Brake balance is seriously affected that is why engineering the vehicle is so exspensive, the brake balance has to be changed and tested.
Stability at speed and on side slopes is dangerously reduced.
The increase in unsprung mass makes the ride much rougher.
Stress on brakes, wheel studs and bearings leads to higher miantenance costs.
getting in and out of the vehicle is very dificult for females and loadimg and unlaoding gear is harder.
The resale value of the vehicle is reduced. and insurance is a problem. Eric.

Eric
some info for you to think about.
My part time 80 runs 31 10r 15 tyres and if i try to reverse up my concrete drive, it spins rear tyres.
Now if i put 35's on it doesnt spin, and i can even reverse up there in the wet. What a difference to traction they make. The contact patch on the concrete is a little wider, but heaps longer than the 10r because there is 4 inches of diameter bigger and smaller amount of pressure in them to keep the sidewalls up.
Now theres a negitive.... sidewalls.... large sidewalls and sticks dont mix.
Andrewwheredayathinkwer mike?

Geez, you guys found a lot of negitive things.
But i want to know how many of you actually owned or driven a 4wd with 35" tyres ?

The only negitive things i would mention is the speedo being out. (no big deal)
Slightly different gearing. If they are on a capable vehical engine wise there is no problem.
Insurance.

35's is the best mod iv done so far & never looked back !