Anyone run on 33"s

[MudRat]

been offered a set of BFGs, will be lifting on suspension by 2", have to trim the back wheel arches etc, what else,  :-k

[mentalmoshio sophs V8i]

front arch will have to be trimmed too, 3.5 diffs really needs changeing . if there 33/12.5/16 u ll need flares to make the tyres legal.

[davidlandy]

I used to run 33s (bfg MT) on modulars.  I had to trim the archs very slightly and I fitted extended bump stops to stop the rear ones rubbing on the inside of the tub, but that depends on your suspension set up.

I also had to adjust the steering lock stops very slightly.

kept original diffs with no issues

 

[chris9119]

BB runs 33" x 12.5" x R15...., you need to cut away alot of arch if you have good lift and don't want to miss out on it's use.

You'll also need arches to ensure them being road legal.

[Tyke]

Been running 33's for while now and must say they are now well sorted.


As for the gearing. . . . . you will notice a difference, especially if you drive the truck on the road . . . . . standard Disco diffs will struggle to pull those tyres, and so will 90's if the truth be known, or any other tyres bigger for that matter.


Get the ratios changed, either in the diff or the t-box and reap the benefits  . . . . . . . .  ;)

[digger]

i run 33/12.5/16 on my discovery all i have done is cut the arches and put a 2inch lift i have no problems apart from they rub on trailing arms on full lock done nothing to the gearing dont find it a problem still goes anywhere i want it to

[boss]

i got the 255/85/R16(roughley 33.8") BFGs there good, i only got a 2 inch lift. you will cope without lowering your diff ratio mine runs fine you may need to invest in some wheel spacers though......

[Budgie]

With this sort of thing the experiences seem to be different for each vehicle.
On mine I've got 33x12.5x15 General Grabber MTs with 25mm spacers (offset wheels will do the same job), cut arches and a +3" lift.

Even with the +3" lift I still get the front tyres rubbing on the inner arches on full articulation, that's with extended bump stops.

As for the gearing, again some don't have a problem, but for me, I ended up changing the transfer box for a 1.4: 1 ratio box from a TD5 Defender after a trip back from the Belgium National. We were quite loaded, but nothing more than the Disco should handle with ease, and going up the M6 there is a long hill, with a head wind I was down to 40mph, in 4th with foot to the boards being overtaken by lorries!!
Now, I've got an Allards intercooler fitted, tweaked injector pump, no EGR and a straight-through downpipe (no cat/particle filter) so there is no reason for it to be this slow.
Around town I found that I couldn't use 4th gear at less than 40mph because it was just too slow and the engine was struggling so 30 & 40mph zones were all done in 3rd.

Changing to the Defender T-box was like driving a new vehicle, the gearing was back to that of a standard Disco on standard sized tyres, I could go uphill without changing down and fuel consumption improved.

Without the wheel spacers or increased offset wheels then you'll loose quite a bit of your turning circle, mine is about the same now as it was when standard.
With the suspension, if you go more than +2" then you'll have the problems with the caster angle changing which will cause the steering to go very light and it will tend to wander across the road. Corrected radius arms will cure this but will cause the front propshaft to vibrate and hit the front anti roll bar. So removal of the front ARB is a good option and fitting a TD5 Disco front propshaft (or one with a Cardon/Cardan/Carden joint) will be needed.
You can re-drill the holes in the swivel housings, where they connect to the axle casing, which will do the same job and should mean that you can keep the standard radius arms, front propshaft and ARB.

So that's my experiences with fitting 33" tyres, have fun.  :D

[mentalmoshio sophs V8i]

i got the 255/85/R16(roughley 33.8") BFGs there good, i only got a 2 inch lift. you will cope without lowering your diff ratio mine runs fine you may need to invest in some wheel spacers though......

255/85/16 or 285/75/16 are u best bet to save buying flares personally i think there better looking than 33/12.5/16. as for drive train its okay doing till it goes bang

[boss]

......if my 255s needed wheel arches then the 285s will!

[davidlandy]

I would definatley invest in spacers - getting the rubber outboard will save the bodywork clouting things. 

[boss]

yes but a disadvantage to the spacers is that you will be alot wider so there is a possiblity that you could get thrown out of a rut(like i did :oops:) because the side lugs bit :?

[mentalmoshio sophs V8i]

......if my 255s needed wheel arches then the 285s will!

nar if u cut the bottem part of the front arch by about 4 inchs in and  the back just a bit more they will fit witout flares

[davidlandy]

yes but a disadvantage to the spacers is that you will be alot wider so there is a possiblity that you could get thrown out of a rut(like i did :oops:) because the side lugs bit :?

I run spacers and have never found this to be a problem.

[Range Rover Blues]

And with spacers you will regain some of the stability lost by rasing the C of G.

[Budgie]

nar if u cut the bottem part of the front arch by about 4 inchs in and  the back just a bit more they will fit witout flares

It's not just a case of clearing the bodywork, it's more to do with staying legal and keeping the tyres covered. No point in doing all that work if it fails the MOT!!

[mentalmoshio sophs V8i]

nar if u cut the bottem part of the front arch by about 4 inchs in and  the back just a bit more they will fit witout flares

It's not just a case of clearing the bodywork, it's more to do with staying legal and keeping the tyres covered. No point in doing all that work if it fails the MOT!!

right 31/10.5/16 r legal to fit so 285s 33/10.5/16 should be the same. cause there the same width.

[Budgie]

It's not whether the tyre is legal to fit or not.
If the tyre protrudes beyond the width of the bodywork and is not covered by anything (extended arch) then you stand a chance of it failing the MOT and/or being pulled by the Police if you drive it on the road.

You said so yourself:

front arch will have to be trimmed too, 3.5 diffs really needs changeing . if there 33/12.5/16 u ll need flares to make the tyres legal.

It's also dependent on the offset of the wheels that you use as to how far the tyre stick out, not the width of the tyre.  ;)

[mentalmoshio sophs V8i]

the only thing with having  a large offset is u lose the steering circle. with tyres of these size we really should have a wheel combo to go with the size. thats a good point u made budgie :clap: :clap:

[Budgie]

It's actually the other way round. With larger dia' tyres you need more wheel offset to push the tyre out and keep your turning circle.  ;)

On mine I did it with Scorpion Prospacers and the turning circle on my Disco with the 33x12.5x15's is about the same as my other Disco with standard wheels & tyre.

[mentalmoshio sophs V8i]

what about the issue of wheel bearing wear more with spacers on

[Budgie]

What issue?

In the 5 years I've been running with spacers I've had one wheel bearing go, and that was though normal ware and it just started rumbling.
If you look after the bearings and make sure there is grease in them then you shouldn't have a problem, it's when you leave them to dry out that they go and that's with or without spacers fitted.  ;)

[adrian]

 so I'm runing on 31.10.50.r15 if i go to 33.12.50. 15 s do i need to get new wheels ?

[Budgie]

If you're running on 7J15 wheels then yes, the minimum width wheel you want to use with a 33x12.5x15 tyre is 8", 10" would be better.  ;)