Scrubbing Tyres

Have just changed two front tyres on my P38 1998 4.0 SE. Both fronts are scrubbing really badly on the inside. Tracking and steering alignment are both OK. Tyre fitters did not know why they would be doing it. 5mm tread on outside... onto the steel wire inside!

Thoughts?

Hi have the wheel bearings and suspension been checked ? and the camber/castor angle been checked sometimes steering geomtry can be fine when camber/castor angle is out

charlotte

Is the check a specialist job? Just passed MOT last week, is it checked then?

Not always although the tyres should have been picked up on if theyre, in places down the wires, stearing geometry isn't in the MoT.

It's not a specialist job to check bearings a little more complex to check full stearing geometry.

Charlotte

Maybe the Viscous Coupling in the Transfer Gearbox has "Wound up"-to check this, park the car on a slope,select neutral and turn steering wheel on full lock.Let off the brakes and roll back,if the tyres scrub there is a strong probability that the transmission has wound up.
If you want a second opinion afterwards,give Ashcroft Transmissions a call on 01582 750400-they are based in Luton and really know their stuff about LR gearboxes.They also have a website www.ashcroft-transmissions.co.uk

I'm working nightshift and have just had a thought.You say the car has just had an M.O.T. If the car had the brake test on a single "Rolling Road",this could have put the nail in the coffin of your Viscous Coupling if the tester was over enthusiastic.The viscous coupling is similar to the unit that operates the cooling fan,the compound inside gets thicker the hotter it gets until it sets hard and locks up the coupling solid-this is "Wind up".

The Borg Warner boxes fitted to the P38 are prone to this.An exchange coupling will set you back around £260 from Ashcroft, but visit their website and do the check in my last mail before you jump to conclusions-Good Luckfrom Ireland!!!

OK. checked all of the above... no joy. Just noticed when I parked it in a car park... not got a level drive way to say the least, that it is not level. Front left is lower. Measured it at the bump stops and it is 15mm lower. It also has a very slight tendancy to pull left. As I said tracking etc all ok.
Any further thoughts if this could be related and how to fix?

Has the front L.H. height sensor had a knock? as this sets the ride height.If the steering geometry, tyres, wheels etc. are in spec. and the transfer box viscous coupling not wound up then the only thing I can think of is possible body misalignment.Have a read of Viscous Coupling faults on Ashcrofts website and the more detailed checks that they recommend,which will involve disconnection of the front prop. shaft from the transfer box. Has the geometry been checked on computerised equipment and are all the ball joints etc. in good order.Is the steering damper okay and are the suspension bushings good?
Can't think of anything else at the moment-good luck.

Hi

Following up on what almost all the others have said if you're tyres are scrubbing inside. Do you have Air suspension or Springs ? either of these could be faulty pulling the car off alignment also if the body is misalined thats serious, I'd stick my original responce being the KPA angles are out (which isn't in the MoT)

Take a walk back from the car kneel down and look at the wheels to see how far they are pointing in or out if its more than say 5 degrees then thats your problem or if the bottoms are pointing in .(Check the wheels from horizontal)

Wheels should point either in or out on a specific camber/caster angle (nothing to do with MoT either)

Also have you got the correct tyre style/size ie Radial/Cross ply/ remould as the tyres can be faulty also have you recently had any of the suspension changed ie track ends, pannard rods, lift, lower kits, bushes.

It can only be one of six things. If you've ruled out all the below then it goes down the exact measurements of components.

Steering Geometry (Full ) Suspension, Body-Chassis, Tyres or Wheels, Brake Bias (amount of Braking per axle). Gearbox-Propeller shafts

Charlotte