Front tyre are not even wear and tear

If it is only wearing on the inside edge your wheel alignment is wrong. The most common cause is the tyre is 'toe out'. The tyre isn't pointing straight ahead like the one on the other side. It is sticking out at the front edge.
Take the car to a good tyre and suspension specialist and get your 'tracking' and 'alignment' checked. They should check your track rod ends and suspension mounts as well.

Assuming the tire pressure is correct and you don't have a bad strut, then the front end alignment needs to be checked.

You know why

There is plenty on the internet to learn
about tire wear

You need a complete rebuild or restoration of the front end

Piece mealing one part at a time over 24 years won't help much,
on a 1990 vehicle

That is the kind of job you need to do yourself.

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

take the car to a suspension specialist shop and have the rear wheels aligned first
have the suspension checked for worn mounts or bad springs
it is very important that the rear end is aligned before the front end
suspect that the suspension rubbers need replacing as it is over 6 years old
the tyre rotation is a myth perpetrated on drivers to sell tyres
when the tyre construction was cross-ply and not radials yes rotation then on cross-ply tyres could get the wear to even out but with radials once the wear is started then the tyre continually wears in that pattern regardless of which wheel it is on
even if you take that tyre of the car and put it on a trailer , it will still continue to wear in that pattern
tyres are no longer rotated but simply put front to back on the same side other wise the belts flex in a new direction in the tread and fail earlier that expected
besides that fact that tyre rotation will not allow you to monitor for suspension problems or wheel alignment problems and cost you 4 tyres at a time instead of two

In the UK we would say 'have the car tracked' .. the wheel alignment checked and adjusted, which is a relatively straightforward and easy job.

However, be aware that there are other causes of tyre wear which isn't rectified by having the wheels aligned.

A bent or damaged steering arm can cause tyre wear. I once owned an old Mercedes that quickly wore one front tyre. Despite having the wheels tracked - aligned - three times, the tyre still wore. It wasn't until I looked under the car myself and found a damaged steering arm ...

A worn ball joint or worn/soft rubber bush can cause tyre wear. Having the wheels aligned cures nothing without first identifying the fault. I own a 1998 Jeep Grand Cherokee which, I am aware, has worn rubber bushes in the front steering/suspension set up. The front tyres wear badly, caused by the worn bushes. The tyres need replacing soon anyway, but I'll wait to get the tracking-alignment- done until after I've replaced the rubber bushes/tyres.

You've had wheel alignment done a couple of times and the problem of worn tyres is still there. It's not the wheel alignment at fault .. there's some other reason such as worn ball joint/rubber bushes or maybe impact damage to a steering arm.

The best option is to get a workshop to put the car up on a hoist for inspection. Tell them that wheel alignment ISN'T the cause of your uneven tyre wear. Any half-decent workshop should be able to find the cause within a few minutes.

A car which has suffered severe side impact - and has been repaired - can have a twisted/misaligned body. This too can cause uneven tyre wear

need a wheel alignment any tyre shop should do them

Because the inner cable has to turn and flex as it spins, they can occasionally break, this can be normal wear and tear. other reasons can be rust from washing, incorrect installation when changing tyres, or the outer has been kinked or damaged. Repace inner and outer as a set, apply some light lubrication.

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.

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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