Very uneven tyre wear - wearing on both inside front tyres

Not really. But the new tire will wear down faster on the same as the old. You need a front end alignment. Could have worn out suspension parts also. Both will cause uneven tire wear.

Bent wheel, defective tyre, wheels out of balance, alignment and uneven tyre wear, defective or worn shock absorbers, excessive wear or lash in the steering/suspension components, binding front brake(s), front brake discs warped or excessive axial runout...

Most commonly it is wheel imbalance that is the culprit.

I would be checking out the wheel bearings for the problem. I would also be checking the front suspension for worn ball joints and steering end joints. Tyre wear patterns indicate unbalance-wheel alignment-shock absorbers and front end wear. I refuse to rotate tyres for several reasons Radial tyres when developing a wear pattern will retain that wear pattern even if placed on a trailer--Wear patterns show a fault for that wheel and tells which wheel and what needs to be done to repair it and lastly tyres wear in pairs so if you have a front wheel drive car why replace 4 tyres when the need is to replace only 2 front ones. Saves about 50% of the cost of tyres. The rotation theory came about from cross ply tyres and does not apply to radials except for tyre dealers profits

Three common faults here are;
1) Steering alignment - if the front tyres are wearing on the insides then the wheels are facing toe-out. If on the outsides then they're toe-in. The only way to really get them aligned properly is by laser light at a garage. Cause can be altered ride height, mounting a kerb badly, wear in suspension.
2) Worn part in the suspension system, most likely a suspension arm bush or ball joint has deteriorated, uneven and/or premature tyre wear suggests this is more likely the cause.
3) Uneven tyre pressures or sizes. If a tyre is down on pressure or one wheel is oddly sized then you can get a diagonal pivot effect accross the car's chassis, causing it to pull to one side.This effect can also happen due to a broken suspension coil/leaf spring for the same reason.

Tyre pressure, wheel alignment,front wheel bearings, brakes binding, tyre wear, uneven brake pad wear and last, could even be a damaged CV joint

Car Tyres will eventually wear out!
I will assume that your Tyres are wearing out quickly and unevenly on one side of one tyres: this is a 'typical' scenario (with some symptoms being vibrating steering wheel, car pulling on one side when braking) when I highly recommend a full wheel alignments as well as getting your Tyres dynamically balanced: a good autoshop or Tyre shop will confirm the issue.
Another possibilty but not as common is your car braking system could be defective thus causing one or more wheels to lockup before the other thus causing tyre burns and wears.
I suggest you consut a mechanic! Hope the information is of some help and let me know how you go!

If they are all terain or off road tyre's then it's normal if it has road tyre's then it would be best to get it checked wheel bearings and brakes.

Uneven tyre wear can only really be caused by either worn suspension or steering components, or wheel alignment angles incorrect. The best way to check this out is to get a wheel alignment carried out by a reputable specialist, as they will (or certainly should) go over your suspension and steering first to make sure there are no faults before they reset the wheel alignment. The other thing to note is that if the uneven tyre wear is bad enough the wheel alignment won't fix the wear problem, just slow it down.
The shimmy could be caused by a couple of things (driveshaft out of balance, tyre fault, wheel balance) but the best thing to do initially is get the wheels balanced first and see if that fixes the problem, and then go from there.
The same company should be able to both the alignment and balance, and these jobs should both be done periodically (at least whenever you replace tyres) to improve tyre life and make the vehicle easier and nicer to drive.

Hope this helps,
Mark.

Unless there is noise or play when cornering sharply at low speeds (parking), the CV joint / boot is still ok. The joint does need grease in there and the rubber boot fitted properly very soon.

As the suspension is set, the axle does little more than provide drive. It doesn't affect toe-in or camber angle.

Camber angle (vertical tilt inwards) is a product of the suspension design, and often cannot be altered.

Weak front springs can also throw this angle out, as the vehicle sits too low.

Toe-in (forward point angle) can and must be set accurately, or you will skid about in wet weather depending which tyre grips more.

What is most important to you, is the tyre design, tread width and outer radius. Also the tyre pressures MUST be mid limit when cold on the front - otherwise excess wear will result.

Having tyres with a large contact area that are too rigid on the front will increase wear to the insides.

Also, it is good practice to rotate the tyres to even-out wear. Usually front tyres move to rear axle, and rears swap sides to front axle. If wear is uneven, pop them off and turn around before refitting. Some tyres you cannot do this with.

If you choose a tyre with a harder tread compound, or ones with "C" at the end of the code, these will again last a lot longer.

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