Mate I too have an 89 gq. Lots of squeekes and other noises. Rubbers all had to be replaced at different stages. The original diff lock vacuum solenoids often either don't work, or break "tubes" can get a new one for under $200. Easy to fit and the Nissan diff lock is one of the best out there. I have tortured mine!!!
The shaking is commonly referee to as death wobbles as they scare you to death when they are bad. All new suspension rubbers/bushes/ Inc panhard arm should fix this if not king pin buses and bearings are the culprit.


And you own a Nissan patrol. No where in those letters can you manage to squeeze a lemon out of. Simply a few worn parts that once replaced can last you another 20 odd years


Tap,tap,tapping in your head