Typical solutions are as follow
Motor Mounts are bad. Best test? Leave the car in 1st gear and drive it in the upper RPMs... Stomp the gas on and off 2 or 3 times and feel for the "clunk" of the loose motor. Highly recommended test: brake torque the car (not with the e-brake!) while in gear with your hood open. Also, check for rubbing spots.
Subframe bushings are shot. No way can I explain a test for this other then as follows... Drive at about 20-30mph and quickly break the wheel left and right twice or so. Make SURE no other vehicles are around and nothing nearby is going to be damaged. Your SHO can spin around on you, it's happened to more SHOs then I'd like to say it has! If you get a lot of response lag when you turn the wheel quickly, then jack the car up ON the subframe near each corner by the subframe bushings, and check for a gap inbetween the bushings.
Tires... That explains it, itself.
Alignment. If you still have the alignment specs for your car, take it to 2 or 3 shops that do alignments and look into free inspections w/ a writeup. It might aid your problem somewhat by explaining the situation to the sales person. In other cases, it might be the bait they were waiting for and will give you some wacky all untrue writeup. That's why I say go w/ 2 or 3 different shops.
Suspension. If it's getting old, torque steer will dramatically increase. That's just the bottom line. How many miles on the struts/springs? Check your struts for leaks by pulling the dust boots and checking around the strut housing up top.
And finally <drumroll> if you DO have new tie rods on your SHO and they ARE grease fitted, then grease them up! 99% of the time, you'll find bad tie rod sypmtoms from rods that are empty in the grease department. This could lead to premature failure and is definitely not worth the risk. So, in my case, I don't leave it in the hands of the oil change guys to grease it all up. I'd buy a tube of Valvoline grease and a gun and go at 'em. This might not solve your problem, or it might be it. However, you'll notice a lot more smooth turning w/o the rough feel or binding effects of dry rods... and you'll save their life! (YAY! hehe)
OOOH yeah.. Check for broken subframe bolts.. Some SHOs haven't had the rear bolt recall done, and some have. However, some have problems after the dealer installs them. For example, my original r/r subframe bolt snapped and then it snapped again after the dealer installed the recall bolts.
Good Luck!
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Neno & The '91 Dark SHO
SHOCAGO Enthusiasts Club -
http://www.shocago.com
137K Mi., Black on Black/Mocha Interior, '94 Mark VIII Rims, 225/50VR16 Comp TA VR, Rod Shifter Converted (Broken stabilizer bolt, still sitting in my trans housing!), SHO Nut Reinforced Motor mounts, Coneless, 3.2L larger crossover tube for intake installed (sure did make the intake LOUDER!), Delrin SFBs, Semi-loud exhaust system...
Ready To Install: Subframe Connectors and Intrax springs instead of Eibachs?
Coming Soon?Konis/Poly setup
18x9 Slicer Replicas on 255/30ZR18s with Coilovers
