Matched Tires

[Canyon Man]

Hello,
New here,
I recently got a 2000 Ford expedition with 187,000 miles on it and there has been no previous repairs or maintenance done to it except an alternator and the oil was changed religiously on it. I took it on a trip but before I did I noticed that the front passenger wheel was worn pretty bad on the outside and needs a front end alignment I assume. So I took the spare which was brand new and installed it. I now have a noise and vibration at acceleration of 35mph and 65mph. So someone mentioned that the tires have to be a perfectly matched or same diameter because of the A4WD and that could be causing my problem. So is this true? Or could I need a new U-Joint and maybe bearing?
Also with this mileage is there anything I should replace or check before it breaks?
Thanks for any help

 

[panda24619]

i dont think it would be THAT big of deal for it. but as long as your not hard on the gas in straight lines or in turns then the front wheels shouldnt activate. but it could be true. get it aligned and see if that helps. if not then new tires.

 

[AaronLG]

Bet it's the good old ball joints.

 

[jacks3am]

If you have a4wd then yes you have to replace all tires at one time, dont mix and match, it binds up the drivetrain, but I think it could just be the alignment! also with that kind of mileage definetly shocks, swaybar bushings, maybe ball joints, tierods, brakes? whatever you feel needs a change its a good idea to do it

 

[KWT2000]

in 99 they went to all wheel drive, and as said you have to have all the tires with in 3/32 of each other to keep the vibrations away and save your transfercase..

you can do the brown wire mod or remove the front drive shaft also...

as for the front tire wear it is most likly the ball joints and inner tierod ends but the idler arm and pittman arm are also suspect...