So I’m thinking of doing my rod bearings on my 2003 3.0 and I’m curious if you guys would do oversized or just standard? I’m getting some light knocking when idling and when cold starting. It has 180+ miles on the bottom end.

I’m not pulling the crankshaft and having it redone or any in depth. It’s pretty much pulling off the pan and putting in new bearings. Has anybody ever done it? Thanks.

 

If you are not having the crank machined to the first undersize, replace with standard size bearings. If there are any scratches on the rod throws that you can catch a fingernail on you are wasting your time. If the crank is smooth and the bearings show some wear, standard size bearings should work fine and your engine should run for a while longer.

 

Cool, that was my thought too. It has been making a very light rattle/knock for a while and doesn’t get worse with RPM’s. But I figured if I ignore it, the it will suddenly get worse one day. Hopefully this prevents major issues and I can keep her going for a while. If all else fails she’s getting a motor. Lol.

 

Take a look and let us know what you find. I think the air conditioning compressor has a bolt in the pan.

 

Well, like Andy said, oversized bearings won't work unless the crankshaft is machined. I saw a guy once do a rebuild on an old Ford 351 and couldn't get it to turn over by the starter or by hand. When his buddy tore it down and inspected it, he found he'd put the oversized bearings on a standard crank! This was back in 1975 when I was in vo-tech school.

 

Well, that was my thought as well. I’ve never done rod bearings on anything in the vehicle. It’s always been a fresh build. But, the crankshaft shouldn’t have wear on it to where the journals would fit oversized, all the material should be in the lining of the bearing itself that’s worn. But, the only other decision I have to make is whether I replace them all or just feel if I have one connecting rod that’s a little loose. It only makes a little noise at idle and cold start. It doesn’t get worse than that.

 

Get some plastigauge and check your clearances before putting the oil pan back on. And some assembly lube or STP to lube the bearings when you put them in.