I own 30 ST3750640AS hard drives with firmware rev. 3.AAE .
Three of my hard drives have low SMART Seek Error Rates.All three of them pass the Long Drive Self-Test of SeaTools. During checking though they produce severe clicking noises and the SMART Seek Error Rate deteriorates. One with Serial Number 5QD1RT19 started with value 78 and right now it's 54 in 3 days time while the threshold is 30.
Another one with serial 5QD1RJ9F started with 68, right now is 41 and it's been to as low as 36.
The clicking noises persist and are continuous for an amount of time until they go away to come back later during usage.
I don't know whether this is a clue but the ST3750 that I have and are made in China seem to be more problematic than those ST3750 that were made in Singapore. These three drives are all made in China while all the drives that are older and were made in Singapore haven't had any problems whatsoever.
I'm really concerned because the other drives have usual seek Error Rates 100 (Singapore) or 78/73 (China) and produce no clicking noises.
Are drives like these with deteriorating SMART Seek Error Rates so close to the Threshold eligible for return? The retailer I bought them from (
www.plaisio.gr) has a warranty policy of immediate replacement from their own stock, but I don't know if they will accept the drives as faulty since they pass most tests and otherwise they seem to be working fine.
I'm really concerned about the safety of my data on these drives.
Is these clicking noises and low seek error rates normal? Should these 3 drives be replaced and should I ask my provider for replacement or not?