Thread: Do 33" Tyres Break things?

Hi all,

I have just bought an D2 (upgraded from my D1 after i wrote it off in some water...) and i am looking into some muddies for it.

I have been told by some of my friends that if i go 33" tyre over a 32" tyre then i will break things, namely my axles and diff centre's and possibly even my tranfer case will not be able to handle it.

The car is a 99 TD5. I understand to fit the 33's i need two inch lift and need to modify some of the body (by building sliders to stop the rub at the front of the wheel arch) and I'm not fussed about that.

I think if i were to go 33" i would only be running them when i took the car off road and i would stick on the standard roadies for around town anyway, so it wouldnt be a constant strain on the car.

What are your opionions anyway? should i just stick to 32's? or will i get away with the 33's.

Cheers,
Shamo

To fit 32's you only need a bullbar, and a 2" lift makes it look more balanced. 2" lift doesn't alter the uppermost travel on the axle, so in that respect doesn't allow you to run a larger tyre contrary to popular belief.

To fit 33's you need a greater amount of lift, and a lift that limits the axle up travel such as with extended bumpstops etc. This type of suspension is typically around 3"+ and will have long travel shocks that require bumpstop spacers and all of the other gear that goes with it such as extended brake/ABS lines, Xmember spacers etc. The bodywork wont have to be touched yet. Some run a 285/75 with 2" and there will be some minor rubbing. 255/85 may be pushing the friendship a little as its slightly greater in the diameter.

Does a 33 break diffs and axles..... yes and no. What breaks the diffs and axles is usually when a spinning tyre gets traction. This peak loads the driveline and eventually something will break. The advantage of the D2 is that it also has ETC, and so free wheelspin usually isn;t too bad to start with, and the inertia is minimised by it when you do suddenly get traction.

There are a lot of people running 33" tyres on D2's and the driveline does seem to generally hold up to these tyres. Mine did for quite a while - at least until I went silly on a steep hill with a step in it and I wasn't going to relent. Well, I did relent when an axle snapped. This was with 285/75-16 MTR's, but I never broke with my 33x10.5 Simex.

The difference in the 265/75 and the 285/75 isn't as significant as you may think. There is a little more diameter, there is some more weight but on most tyres the treadface mould is the same between the 2 tyres.

If you drive it sensibly to moderately with 33's on then you will be fine. If you go carefree with it and lose all mechanical empathy then you will break it. The stupid thing is that there is a lot of gospel folk law that gets bantered around, such as 32" is fine, 33" will break backing out of the driveway. Lift it 2", if you go to 3" you will roll it when you turn out of your street, If you spring lift it 4" it will roll - lift it 2" springs, 2" body etc etc etc. I've probably heard most of it, and you will have to decipher what is good and what is bad.

BTW, someone comment on upgrading the driveline. High Tough rears are the go, but for the front they are not necessarily the go as you wont get significant strength from them. You'll need to look at Ashcroft front axles and CV's. These are now the only real option.