how do you check the shift cable in the 1992 gmc typhoon?

Question

the car is not always finding park, or you have to get the rpms up really high for it to shift into third gear Could the cable be streched?

Answer 1

Remove the shift cable where it attaches to the trans shift lever and manually move the trans shift lever through the gears and back to the park position---check for slop or play in the shifter or where the cable attaches to it....if the shifter cable does not line up with the trans shift lever while both are in the park position, adjust the cable or replace. Shifting into third gear problem could be related if the trans shift lever is not fully shifted into the proper setting from a mis-adjusted cable...it also sounds like a possible bad vacuum modulator, low internal line pressure or worn friction plates in the trans....drop the pan and check for lots of friction plate material in the pan and condition of the fluid and filter...a plugged filter can cause this too, may be time for a flush or if bad enough, a replacement trans.
Get the shift cable adjusted or replaced first before checking other issues.