HP LaserJet4 Plus printing gray on print copy

[Dennis0818]

Had gray streaks on printing.  Replaced fuser, no change.  Replaced toner cartridge and now the problem is worse than ever.  Any ideas would be appreciated.  I know it's an old printer, but has been bullet proof until this time.

[east2100]

It sounds like it's a bad cartridge even through you have changed another new one both of them are no good.

Check the surface of the drum if it's covered with circles of toner as what you printed out then that's it.

The good one.

The bad one.

The toner powder itself can be save longer far more than the whole cartridge all together.

If you like you can keep it until one day you can pour it into another empty one.

[Dennis0818]

That is exactly how the new cartridge looked when I checked.  The vendor I ordered from was very understanding that the cartridge was probably defective and is sending a replacement.  Thank you for your help.