So I've been reading several post re: low oil pressure , and having that problem myself, I joined your forum. I have a Buick lasabre with a 3800 with 150,000k
When it'* idling, the oil light comes on, so like many before me, I put mechanical gauge on , and the pressure is 5-7 lbs hot idle. When reved it picks up to 25-35 lbs. I have bought oil pump repair kit from melling,but after reading these forums, it looks like these pumps don't go bad, I did however replace the regulator & spring. No change, so I've pulled a couple of rod caps and see wear, not enuff to make noise however, the engine has never made any bearing or low pressure knock or rattle.
So here'* the $64000 question? Did the low oil pressure cause the bearing wear? Or did the worn bearings cause the low oil pressure?
If I replace the rod bearings, will I get oil pressure back?

It takes a lot more then just changing the bearings, it needs to be rebuilt. Your best bet if your looking to rebuild is to find a new short block and transferring all your parts over to that. Does the engine start off with good pressure and then drop off as it warms up?

Yes, it starts off cold at 25-30 lbs then it drops as it warms up .
My 5-7 lbs at idle , is warmed up , fans cycling

Because you had no lower end noise I would suspect a cam bearing over a rod bearing. Either way, it'* a total short block rebuild. A new short block or a total engine replacement is your best bet. The cost of having the short block you have rebuilt may make replacing the engine a better choice. Where abouts are you located. Might be a member in your area with a engine. Also, is it a L67 or a NA engine?

I guess I am lucky, I have 143,000 on my Reatta with 35 psi at idle (hot or at 70 degrees) and no leaks, yet. Same engine that Pontiac used, yes? Richard