1992/93 pete with cat oil problem

i got a buddy with a pete dump truck that has a 3308 cat in it. the truck was running great reg. oil change and not driven hard...he was on the way out of the quarry and the oil press. drop to 0 so he turned the truck off and had it towed home to be safe...he cranks the truck about 1/2 times a week in the yard and it has great press. but after the oil warms up it starts to tap and little in the top of the motor...could this just be he needs to have the valve adj. or is the motor shoot.....hate to see him (older guy) get ride of his truck and its not as bad as he thinks..he thinks he need to rebuild the motor ( got a price on it 15.000.00) so he said no way he'll go drive for someone else before he do that...could the oil pump be changed with out a complete tear down or rebuild???? thanks guys for any help mike

 

so i geuss a rebuild is in the near ...thanks mike

i know cats are on the high side for a rebuild but whats the going price or is it better to just buy a tested motor and go from there....

 

ok guys talk with the owner today of the dump truck and he told me that the motor is a 3376.. also he told me that it didnt really loose the press. it dropped down some ...this is what he saisd he did he was going out the rock quarry which is down a hill and was in the wrong gear and the truck topped out in that gear down hill before he could get his thoughts togeather...and way the motor then had a tap in the top end and not the bootm..he had the truck towed home and cranks it and let it run for hrs at the time and think that some how it may need the valve adj. from the motor being topeed out down the steep hill...its this possible how can you check for something like this ....he didnt think about keeping a eye on the oil press. but i told him tol take a look at it next time and see if it is low once it warms up... any idea on what to look for or check to see if the truck if fine or not his 60yrs old but works everyday thanks mike