Variables to match when finding Western Digital donor drives

[hybris2k]

Hi guys!

I was wondering if someone can answer this once and for all.. I have been searching the web and I have been talking to my senior engineer but I just can't get a definitive answer.
When I need donor heads for Western Digital drives, I know that luck is a big factor but how to increase my chances?

I have the following drive right beside me:

MDL: WD2500JS-40TGB0
DATE: 17 AUG 2006
DCM: DBCAYT2CAN
Product of Thailand

I know that the DCM is the major key here but one site says you should match the whole thing (which is nearly impossible). Another site says that the 5th and 6th letters are the most important; "YT" in this case. A third site says that the five last letters are the most important; "T2CAN" here...
My engineer friend claims that the firmware ("TG" in the MDL-number) is crucial but is it? Does the date matter at all? Sometimes it seems like drives manufactured about the same time matches better... Any truth in this or just a feeling?
And of curse manufacturing country may play a part too...

Please, if someone knows about this, I urge you to answer!

Thanks in advance!

[hybris2k]

I am surprised!

Almost 24 hours and not one single answer

Don't you guys know or do you simply not want to share info?

Take care anyways!

[HeadCrash]

Ohh Hybris2k, dont blame us for your laziness. You knew how to post in this forum, you should know how to search.

If you expect "spoon fed" in this forum then "Taker care!" Adios Amigo.

[hybris2k]

Man.. I tried to search for it but I couldn't find any solid information

It was links to other sites, which I told about in my first post. I am just trying to make it clear once and for all.
Maybe it is completely impossible to make it clear because every family is different from other families. In that case a simple "the is no clear answer" would suffice.

Do you seriously think I am trying to get it all for free when you read that sites differ in information and that I discussed the issue with my senior?
I was hoping that someone here with enough solid knowledge could tell me. If the answer was simple and easy to find, much fewer words than the generic "RTFM" answer would be enough, don't you think?

I have a sinking feeling asking here was no good idea since we all need bread on our table and roof over our heads in the end

[hddmania]

If you purchased the expensive tools, they do come with the donor info & live person to speak to regarding the donor info on a specific drive...

[pepe]

It is almost impossible to make a general rule.
I can swap heads within one family even when the model number does not match (middle two figures), but it is really hard to tell which model numbers belong to a family without first having it in my hands.
According to my experience the 3rd figure in DCM must be matched for MHA compatibility.

pepe

[harddrivespecialist]

Every tech has their own requirement.
Just model number will be good enough for one person, but another one will require full dcm match, date, manuf. site, motor number and etc.

[maux]

I expect very few people know just the criteria that determines which particular parts can be swapped with what rate of success with any given make or series of drives, much less any overall rule for all drives. Don't worry about the more guarded posts here.

[hybris2k]

Thanks a million for the answers, guys

Too bad it was as hopeless as I expected though.
I heard that some companies actually reject WD drives with bad heads because of the geometry issues.

Oh well, it was great with some extra input on the subject!