willysmjeeps.com

Is there a difference between an M38 and other
parking brake drums?

Yes & no! There are variations like the Early WWII outer shoe type and the M38A1 outer shoe type but the Late WWII, M38, CJ2A, CJ3A, CJ3B, CJ5 & CJ6 with the F134 and L134 all used the same system (shoe inside the drum) and all should interchange since All used drum PN A9332 or ORD# 7371010.

Thanks Wes.

The reason I ask is I've been offered a takeoff but it has two extra holes
drilled in it I've not seen in NOS and my takeoff. They are a little larger
than the bolt holes and on either side of two of the cast openings.

The offered one has not been cleaned so the casting numbers are
not available.

There are also different rib configurations. The late MB and very early CJ2A are unique

Keith, Since the part number remains the same, A9332, Late MB thru CJ5/6 are you seeing the rib differences on the factory blue prints?

One would think the casting numbers would be different as well.

Any thoughts on those two holes? Won't they affect balance?

I haven't checked any drawings, but they are easy to tell apart.

Late MB and Very Early CJ2A



CJ2A /M38/CJ5

Brian, It was not uncommon for a basic casting to live thru several machining changes over it's life with the changes being made on the blueprint as dated alterations or notes.

Thanks guys.

Ok, so Keith's bottom photo shows three additional holes.

What gives?

I believe those are balance holes

That is what occurred to me but I did not want to assume anything.

Reinforcing Wes's point: