LG Dryer Drum Rumble

[Kranky]

LG DLE5977W Dryer - I have a rumbling noise that was first noticed on starting a drying cycle then after a few loads is happening all the time.  I have repaired rollers, drive belts, etc. in older dryers so my first thought was that but after reading some other posts here I am concerned that it might be the drum.  When I first turn the drum (top removed) I get a distinct clunk from the back roller.  Then much smaller bumps as in continue to rotate.   Doesn't seem to be any bumps or dents in the drum surface.

Question is do I have a roller or drum problem?  Or could it be something else?  I would like to order parts before disassemble further if possible.  Are there any other suggestions?  Thanks in advance for any help.

[BrntToast]

look inside the drum at the seam, LGs split drums at the seam

[Kranky]

Turned out to be a fairly large flat spot on a roller.  The roller turned freely so I am not sure how it happened.  My guess is that something got temporarily lodged in the roller.   In any case I now know how to disassemble.  

[whirlpooltech]

What colors were the rollers?
I believe LG used some red colored ones that would get flat spots and they would get replaced with new ones that had harder rubber on them.

I think the replacement rollers were blue in color.

I have not worked on many LG and BrntToast would know better then I about the roller changes.

[BrntToast]

new rollers are blue, all it takes for them to go flat is a couple weeks with no use and the tension from the belt
if the new rollers you installed were not blue return them cause they will go flat
and yes, i think the originals were red or pink, havn't seen one of those in a while now though

[Kranky]

The bad roller was white.  The new one is blue.  Both were made with fairly hard rubber.  The dryer doesn't sit very long.  Maybe 3 days tops.  Wife says that there had been a screeching noise when the dryer first started up for a week before it started rumbling.  Have a feeling that it could have been overloaded too many times. Now I wish that I changed the other back roller while I had it apart.  The fronts would be a bit easier.  Could be changed without removing the tub. 

Thanks for the reply.