Thread: Front tyre size smaller than rears?

Originally Posted by Chad

Hi

I know I ask some prettty dumb questions and this could be well one of them, but if I was planning on running a different diameter tyre on the front of my series 3, about 3 inches smaller in total, would this create problems in transfer, diff gearbox or otherwise.

I know it seems like a dumbe question, but I am building something, based on a landy 109 v8 ute, and the way i am settting up, looks like this is how it will be.

Fronts 225/35/20 rears 265/35/22 so

diameter totals being 671mm front 744mm rear

Thanks again Chad.

Will post some pics soon. For anyone interested.

In 2wd no problem, in 4wd big problem and transfer case go boom.

the 109 series 3 v8s are full time 4x4 aren't they?

so I guess best to remove the front tailshaft?

Any other way around it?

Thanks for the reply.

Chad

Stage 1s (V8 S3) are permanent 4wd, so it will cause problems with the centre diff working overtime.

umm..... WHY?

ok..... given a lil more info in a PM, i'd suggest this:

1: select tyres with a aspect ratio to bring front/rear tyres to the same kinda size
2: juggle front/rear diff ratios to suit the tyres (3.54 front-4.11/4.44 rear) and adjust tyre size to suit
3: convert it to run RWD only - a LOT more freedom in regards to gearbox selection

have you considered consulting with an engineer about this? in several states, you WILL have issues re: tyre/wheel sizes, load ratings, etc

yep

been to engineer.

found wheels/tyres load rated.

was just asking as i wasnt sure if there was a diff type mechanism in transfer case etc. might be just as easy to remove the front tailshaft.

if i remove whole diff assembly etc, changes the whole regs etc regarding engineer.

are the rear diffs strong enough to handle being run withouth the front driving as well?

obviously won't be using for 4wd, just looking to build something different, plenty of f100/chev rods etc... not many landys.

might just settle for front and reaer 265/35/22, just not sure with the amount i am planning to lower it, if it will still fit up under front guard etc...

thanks for your ideas.

You may as well run 2WD and use a 9-inch Ford diff at the back.

you can still run the front diff, just gut it, no diff centre, driveshafts, CV's, etc, just blank off the hole left by the diff carrier with sheetmetal

you do realise that retaining the original suspension is going to be your biggest enemy in terms of getting it low, right????

best to find a HQ-WB ute chassis and drop the bodywork onto it