Unable to drive straight

I just purchased a 1997 Kia 4x4 Sportage, 5 speed, 4 door with 37,000 original miles. I replaced all 4 tires with Michelins. Took the Sportage to the shop for an aligment since the company that sold me the tires do not do aligments. I also ask them to check for the inability of the car to go straight at any speed. I have to keep correcting constantly left and right to go in a straight line. I was told that the front wheel bearings were loose and needed to be re-packed and adjusted. No other problem was found with the front end. The work was done for $200, but the problem is still the same . Can anybody tell me why this Sportage wont keep straight. Thank You!

I assume the problem is present in 2WD.
1st and important detail: do you use standard original equipment wheels or some kind of offset rims?

I assume the problem is present in 2WD.
1st and important detail: do you use standard original equipment wheels or some kind of offset rims?

The steering problem is on 2 or 4 wheel drive mode. The tire size are the same as factory specs and the wheel are also factory original.

I'm puzzled!! With that low mileage, (unless done in severe conditions) I do not think of worn out rubber bushings..
This link
www.avigex.ca/kiasport/steering.pdf
is copy of KIATECH diagnostic page..in my opinion it does not help much, because you have had probably all of this reviewed...I've checked on 4x4WIre ..for some post on similar problem..., to no avail.

NOw this: I've driven my Pontiac Transport for more than a year with erratic steering, looking all over the place , alignment, tire size et al, ...to finally realize that it was the lower ball joint, that I had checked several times before, but I was biased by the fact I had replaced it a few years before .....

So, maybe something has been missed anyway.

I just picked up the Sportage from the shop that has done all the work untill now. ( I had re-ckeck the aligment) Told me to go to the dealer and see what they say. Can this be the rack & pinnion or the power steering pump?

..power stering pump do not cause erratic steering..just harder to steer. By the way, this is a worm and gear type steering, not a rack and pinion, and there is normally an adjustment that keep worm and gear in close contact--what they call preload on the diagnostic page...there might be something there..rare though. This subject did not come anywhere in other forums, so you are the guinee pig on this. Let us know what you find.
?!? DId you check the bushings for the trailing arms on the REAR axle??? Just to be sure.

I will have the dealer check the bushings and diagnose the problem, and let you know. Thank's for your help!!

I will have the dealer check the bushings and diagnose the problem, and let you know. Thank's for your help!!

Well, after more than a week I was able to fix the problem. The guys from PepBoys could not do anything for me. Everything checked out OK and told me to go to the Kia dealer. So I did. They had the car for five days and gave it back to me saying that after consulting with the factory techs and their best mechanics they could not find the problem. Suspension, bushings, ball joints,gear box adjustments, etc., etc. was fine. I went to their parts dept. and ask for the cost of a steering box, $1300...plus tax and $200 labor to install.
Got on the internet and found one for $325.00 freight included. Bought it , had it install at PepBoys for $75.00 and the problem is solved, and the Kia Sportage now drive straight and with no problems. Thanks for your help and I hope someone can use this information.