Have a 1998 honda civic that has a little shake to it while driving 55 mph down the highway.. If I go 70 the shake calms down a little only because I am driving much faster but it is still there because I can feel it and see it on my hand while holding steering wheel.. I just took it in to get a wheel alignment and the shop said they made adjustments and the only thing I needed to replace was the rear struts.. So I put brand new rear struts.. I am hoping they would have told me if I needed front struts as well? They said they were able to make adjustments to align wheels in front so they said no need to replace them.. But I do not know what could be causing my steering wheel to shake a like it does and do not want brand new tires to wear if in fact it is bad front struts or weak front struts.. Any clues what could cause this shake?