[steve65]

Hi all

I have just bought a 2001 Grand Vitara v6 and it needs new tyres, so I am looking at getting some AT tyres. I will be getting a 2" lift later on, i'm wondering what is the max size tyres that can be put on without a extra lift.

Thanks Steve

[Gwagensteve]

The 2" lift makes no difference to the maximum tyre size you can fit.

225 75 16's are common but require some hammering of seams and trimming of plastic.

[steve65]

Do you think 235/70/16 would fit too or will I need to do some hammering and trimming also.

Thanks

[steve65]

I went with 225/75/16

Thanks for the info.

[vegie]

How much hammering and trimming was required?

[steve65]

vegie wrote:

How much hammering and trimming was required?

I only needed to trim the front plastic inner guard.

[Gwagensteve]

I suspect you haven't fully compressed the rear suspension yet. The old shape GV's I've seen on 225's all needed hammering of the rear guard lip and trimming of the plastics to prevent tyre damage/jettisoning of trim

[steve65]

It was fine in the rear, now i have a 3" lift front and back. So all good.

[Gwagensteve]

So have you spaced the rear bumpstops?

[steve65]

No I haven't, what needs to be done.

Thanks

[shep]

steve65 wrote:

No I haven't, what needs to be done.

Thanks

If you have no scrubbing then nothing needs to be done

[steve65]

Thanks.

[Gwagensteve]

Except that will have scrubbing, you just haven't yet.

[Gwagensteve]

I'll explain in a bit more detail.

If you have fitted longer springs to achieve the lift suspension lift, all you have done is move the rest point of the suspension when the car is static. When the car is in motion, the axle's movement is limited by the extended length of the shock absorber (droop) and the factory bumpstop (compression). This compressed position is the same as a standard car - the lift springs don't change it.

Lift springs can give the impression they allow larger tyres to fit because in "normal" (road) use the suspension only moves through a small range of travel, so the new rest position moves that working range up and away from the interference point.

However, when you fully flex the suspension off road, or you're carrying a heavy load, or you unexpectedly load the suspension hard (like go too fast over a drain on a track) the axle will reach the factory bumpstop and tyre contact will occur.

In the case of the GV, it will cut the rear tyres on the leading edge of the rear wheel arch, and catch the plastic sill trim, pulling it down and off the vehicle.

There is nothing different or unique about your setup - every GV with 225's I've seen requires clearancing to run a 225.

[steve65]

Ok have had car fully loaded but no scrubbing as yet, when you say space bumper stops what needs to be done.

Thanks.

[Gwagensteve]

take the rear springs out so the suspension fully compresses onto the bumpstops. trim/hammer as appropriate. If you d contact at the top of the rear guard excessive, space the bumpstops. ARB sell a bumpstop spacer for the front of an XL-7 which I believe will work in the rear of your GV. I believe regardless of bumpstop spacing, you'll still have some contact at the leading edge of the rear guard.

Also consider getting the chassis up on jack stands and fully compressing one side only with a floor jack whilst the other is at full droop (rear shock fully extended) - the compressed tyre will move up further in this scenario, but because it tucks in away from the guard lip contact isn't often as bad.

You've fitted substantially larger tyres than standard - this is the normal process to go to when you've done this. As I've said, better to go through the process now rather than hit a big bump offroad and cut the tyres/remove the sill trim.

[steve65]

I will take a look and do it anyway better to be safe than sorry. Thanks for the info.

Thanks

[30ONA]

Are There any additions to the above info to install 235/70/16? Guards Already removed and mud guard trims pushed back.

[30ONA]

If you have access to an RTI style ramp could you use this to determine the travel and clearance for each wheel/tyre? Would be easier than finding 4 jack stands and removing the springs. Then when on the ramp measure the clearance at each wheel arch minimum gap to determine how much bigger you can go before needing to change suspension?