Mitsubishi Delica Owners Club UK™

fiftig · Joined: 08 Apr 2006 Posts: 3 Location: crewe, cheshire

hi all, could you please confirm for me that we should be running the same size tyres front and rear.
I have at the moment 215's at the rear and 225's at the front and the nice man at kwik fit says this is
very naughty and wants to sell me 4 new ones ! !

Google · Sponsor

ricky · Joined: 17 Feb 2006 Posts: 98 Location: york

makes no differance front to rear as long as they are the same across the axle,
_________________
smell my finger!!

L400_Davet · Posted: Thu Jul 19, 2007 18:28 Post subject:

I thought the smaller size had to be on the front,

and they should be the same size on each axle.

just don't try using 4WD with different size tyres.

Also ATS may be worth a look as they had 15% off for 2 or 25% of for 4

also if you don't need them straight away you could try

http://www.mytyres.co.uk/

http://www.blackcircles.com/

just to mention a couple, they deliver to you or to a fitting station for you,

you might want to try a different size also, 235/75/15 is the average and they are easier to get Laughing

hth

Dave
_________________
1994 L400 all blue 2.8td 5sp manual, with a L.S.D.

MDOCUK Lifetime Member 112

Lewis · Posted: Sat Jul 21, 2007 11:01 Post subject: Re: tyres

fiftig · Joined: 08 Apr 2006 Posts: 3 Location: crewe, cheshire

many thanks ,will be taking your advice and getting same size all round. :D

strangerover · Posted: Mon Jul 30, 2007 23:09 Post subject:

Now I understand how the SS4 (Supper Select 4) system works....

if you are running ONLY in 2WD then so long as the wheels are the same on each axle then no problems.

If you ever plan to use 4WD you MUST use same size tyres all round as we do not have a open centre diff on the L400's,
on the SS4 vehicles its a Viscous centre diff so any difference in rotation front to rear over a certain amount will cause the diff to eventualy die.

The diff works by allowing just the rear wheels to be driven untill they start to loose traction and at that time 50% of the power is sent to the front wheels.
So if the front and rear wheels are different sizes then the front and rear prop will spin at different speeds, and thats how the system works out if the rear wheels are spining / loosing traction and then engages the viscous diff.

hope that makes some kind of sense.
_________________
Regards
Mark

THE KICK INSIDE · Joined: 31 Jul 2005 Posts: 1592 Location: Staffordshire

yeh thats what i understand too...now the width (225, 215 etc) wouldn't make a difference if the rolling diameter was the same (i.e either through wear or profile)..

the way a viscous diff works as i understand it is very like an autobox - essentially he power to the rear wheels is dirrect but a viscous (oil filled) cluth mechanism exists which is essentially two impellers with oil between them, when all the axels are rotating together ther is no difference in speed so the oil just trundles round..now if the rears spin the rear impeller rotates faster than the front impeller and the drag from the oil now starts turning the front impeller (aka provides drive to the front wheels) needless to say the sheer forces on the oil molacules are considerable as can be the heat genrated!

This is certainly the viscous clutch mechanism used by volvo and they have had a LOT of failures (including units physically blowing up by all acounts Shocked

) I know for a fact in the USA there have been issues with people replacing just front or rear tyre sets - thus unmathing the worn to new tyre diameters - and using the space saver has also apparently destroyed them! (apparently the owners manual on the xc70 tells you not to use it even thought its there.....)

I think the unit in the L400 is quite a bit more rugged than the volvo unit (which was a bit of an afterthought and also suffers from crown wheel problems - well what do you expect once ford took over....sorry confirmed old swedish turbo brick driver here - (what goes form 0-60 faster than a xr2, can do 140+ and can carry a bed while doign it - that would be the red block turbo brick)

anyways the best advice is don't run differnet tyre sizes on a 4WD!

(and don't buy a modern volvo unless you like a rather nice ford...)
_________________
A Delica - ITS LIKE A SWEDISH BRICK...ONLY BIGGER!

andyj · Joined: 08 Sep 2006 Posts: 2412 Location: up norf

for the love of god don't do it...i nearly killed my diff running different tyre sizes on my Deli

if the tyres are reasonably worn replace the lot, then sell em on ebay...camskill.co.uk have got some good deals about 50 quid a tyre for a decent make