Here is my problem 95 jimmy 4.3 w 198,000 on original engine. It just developed a rod knock the other day I dont think I spun a bearing. Anyway did a comp check 166 to 170 on all, so that goes. I need to keep this for another year or so it is my work truck. Should i go for justA lower end rebuild or A new long block block. How long do u think the upper half will hold out? I put 175,000 on this truck and it has been very well mantained.

 

With that good of compression, you should have no problems with the upper end of the motor.

You will still probably want to pull the motor and have the crank mic'd to make sure that you have not scored a journal. You will also want to polish up the crank journals before putting it back in if there is any minor scoring. A new main and rod bearing set and you should be good to go.