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      05-19-2026, 05:51 PM   #3
omgzirra_exe
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Quote:
Originally Posted by e30gentry View Post
Need some help to see if anyone has answers.
I was either shipped two sets of upper, two sets of lowers or have no issues at all but can’t seem to get a definitive answer.
My WPC treated ACL rod bearings have the stamping/part number.
STD
DEC24
1580H
This is on every bearing with no other markings.
I will not half the bearings have this stamp where the bearing tang/tab is while the over half has the stamp/markings on the side with no tang/tab.

Does anyone have answer if the set is wrong or know which side is upper vs lower?
Well, if you bought regular ACL 1580H bearings and then sent them out for WPC treatment, the top and bottom bearings would still be identical.

Normally with ACL bearings, we like to mix and match the 1580H and 1580HX variants to get an ideal clearance of around .0024".

Quote:
Originally Posted by Brandoch View Post
I believe ACL bearings are the same for upper and lower. However someone chime in if I'm wrong.
correct!
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