Quote Originally Posted by John_D View Post
Hi guys.

Years since ive posted here

I'm in the market for an E92 M3(pre-lci), my question is about Rod bearings. Most if not all of them would likely have had them replaced and generally are advertised as such.
My question is: Are the replacements usually a once-off higher clearance bearing that is less likely to have the same wear as before? or are you likely to be still needing to replace them on an ongoing mileage basis?
I don't fear doing it or getting it done, just want to be armed with all the facts.

John
They're a service item really, you can use increased clearance bearings but then the risk of the car having issues with oil pressure at high temps is possible. There's all kinds of claims and white papers on the subject but from what I've learned, the most effective preventative maintenance is a careful warm up routine. Also, you don't know the condition of the bearings without a visual inspection as there's no way to account for every start up.

There's a decent amount more preventative work outside of the bearings too, injectors, throttle actuators, water pump, thermostat, coolant temp senders etc.