Thread: Brand new Puma drifting to the left

Originally Posted by BigJon

Where will you put a shim in to change the caster?

Ok, just been to the wheel alignment shop - alignment is perfect. The tyres are 2.3 all round, but tyre pressure does not affect the drift.

The shim will have to go on the front left radius arm, since the left wheelbase is approx 4mm shorter than the right one.

Err, shimming the radius arm fowrd one side will not change caster on an individual swivel housing as the axle housing is a rigid 'beam', this is achieved by slotting the actual swivel housing to axle housing holes, and rotating the housing slightly. If you needed an overall caster adjustment, then only offset bushes will help. Shims at the end of the radius rods will only effect the wheelbase each side.

JC

Originally Posted by justinc

Err, shimming the radius arm fowrd one side will not change caster on an individual swivel housing as the axle housing is a rigid 'beam', this is achieved by slotting the actual swivel housing to axle housing holes, and rotating the housing slightly. If you needed an overall caster adjustment, then only offset bushes will help. Shims at the end of the radius rods will only effect the wheelbase each side.

JC

JC, thanks for the info. not sure I understand all of it, but will check with my indie mechanic.

There is a caster difference of 0.4 degrees - does this correlate to the 4mm wheelbase difference or is the latter something different?

Originally Posted by Naks

JC, thanks for the info. not sure I understand all of it, but will check with my indie mechanic.

There is a caster difference of 0.4 degrees - does this correlate to the 4mm wheelbase difference or is the latter something different?

POSSIBLY, but a 4mm variation is pretty normal in Defenders, I have seen a D1 with 11mm difference. But don't worry - After the caster change via the method listed below, it may improve or get worse depending on which way it has to be rotated

Have a look at the way the swivel housing is bolted to the end of the axle housing. Now picture rotating the swivel housing around to get the caster right, maybe only a half bolt hole will be required, not certain. .4degrees is about equivalent of a 25mm suspension lift IIRC.

Anyway, this may be the only way to cure the unequal caster, so more measurements RE the positioning of the axle flange onto the end of the axle tube needs to be investigated. May have been welded on rotated slightly


JC

Originally Posted by justinc

Err, shimming the radius arm fowrd one side will not change caster on an individual swivel housing as the axle housing is a rigid 'beam', this is achieved by slotting the actual swivel housing to axle housing holes, and rotating the housing slightly. If you needed an overall caster adjustment, then only offset bushes will help. Shims at the end of the radius rods will only effect the wheelbase each side.

JC

Agree 100% with this, hence my earlier question!

Originally Posted by danske

he adjusted the front end to address this ( sorry dont know the tech terms ) and it has been fixed. basically he desensitised the camber adjustment and it has worked.

How did he do this, since one cannot adjust the camber on a Defender, only the toe?

Ok, I spoke to the guys at 5th Avenue Motors who do the suspension work for LR Stellenbosch. They found a 20mm difference between the left and right wheelbase :shock:

The caster difference is only 1 degree

Landy will be going back to them to see if they can sort this out...

Hi All

If the left wheel has one degree less castor than the right and you drive on the left side of the road then assuming that your roads have some camber the car would pull to the left quite strongly.

I used to try and set up vehicles with about 15minutes more castor on the left with our fairly low camber roads here in the Territory. Hope this helps

Regards Mark