Hard Shift is it normal???

So I have a 92 Olds Bravada 4.3 litre not the High output engine. Has Towing package fully loaded besides the engine. Anyways when shifting into Drive or into Reverse it seems to feel really hard theres a clunk and you feel it go into gear. Is this normal? When I drive the car city/highway it shifts fine the only time is when I put it into drive or reverse and it doesnt matter if its just started or if its been driven for a while and warmed up. I hope its just normal but my dad said that some joints in the driveline might need replaced and that I should check them out. I am going to do that of course but I just wanted to see if this was a common thing. Thanks in advance.

Your dad's correct, worn universal joints cause the noise you're referring to.
While you have the driveshaft(s) loose, check for greater than 1/8 turn slack at differentials...winter's a comin', check your coolant & put some fuel antifreeze(alcohol) in the fuel tank. Are your windshield wipers in good shape?

Thanks Chris Yeah the wipers are new, don't worry I'll prep it for winter

I forgot another problem with the "clunk" symptom, bad motor mounts.
With the hood up, motor running, parking brake set, left foot on the brake, transmission in Drive, slowly apply some throttle with your right foor while looking at the motor through the gap between the hood and cowl.
If the motor raises up more than 1 inch, the drivers side motor mount is likely broke. Check with your dad on that.