Start with the standard trouble shooting items,Tune up parts,dirty/fouled plugs? Are the cap and rotor in good shape? Is thefuel pressure,in spec? When was the fuel filter last changed? Are there any broken vacum lines,Hook it to a scanner,see what live data is telling you.
Another thng to check is the runout on the drive shaft(s) .050 max. Are there any weights missing on the shafts?Has anyone beat on the shaft to change a U joint and dented it at the weld?
Disconnect the throttle cable and see if the problem persists, also make sure that there is no binding or kinking in the routing of the throttle cable. Check to see if the TBI base gasket has failed and is contacting the throttle plates.
Chek your tires for being out of round. Also check your that the wheels are not bent. Check for a bent axle . Check to make sure the drive shafts are in phase. Check for dirt/rust build up on the wheel to axle mating surfaces.
And you have disc BRAKES not breaks. :33:
It is the law here in PA but most LEO's are to lazy to enforce it.
My '97 has them attached with just lip screws, as does my brothers '98 K2500. My '88 K3500 had them through bolted. So, Maybe it was what they had on the Assembly line or that certian models had the flares through bolted?
It still has to pass 25 year federal inspection to be allowed to be imported unless it meets certain specs.
https://usacustomsclearance.com/process/how-to-import-vehicles-to-usa/