PN help

[volaredon]

I found a set of new (but old) TRW mains in my attic and it's written on the box "MOPAR SMALL BLOCK STD MAINS" part numbers are 5024M and under that is MS 3264. Are these 360 or "except 360"?
And by the number are they steel, steel/babbitt or tri metal????
Next question I thought I had read somewhere that they moved the bearing location notch on small blocks around 1973 ish around the time they got away from floating wrist pins and went to pressed style. ( Yes I know that "that" pertains to rods) Was the moving of the bearing notch related to Rods or mains?

 

[volaredon]

Ive looked and closest I could find (definitely newer stock) was 5024 MA. There's definitely no "A" in the PN stamp on this set
And PS no they're not for sale. My son has an engine he is working on and if they're what he needs they're going to him

 

[Professor Fate]

I'm no help on the part number, but remember that sometime in the late '70s ('79ish?) the thrust bearings changed- this may or may not affect whether they can be used in your son's build. I don't believe the later (bigger) thrust bearing can be used in an early block, for example.

 

[Vaanth]

I found a set of new (but old) TRW mains in my attic and it's written on the box "MOPAR SMALL BLOCK STD MAINS" part numbers are 5024M and under that is MS 3264. Are these 360 or "except 360"?
And by the number are they steel, steel/babbitt or tri metal????
Next question I thought I had read somewhere that they moved the bearing location notch on small blocks around 1973 ish around the time they got away from floating wrist pins and went to pressed style. ( Yes I know that "that" pertains to rods) Was the moving of the bearing notch related to Rods or mains?

View attachment 1716534503

View attachment 1716534504

TRW main bearing set number MS3264 fits 1974 (after engine date code 812) - 1991 318 engines with 3.530" maximum flange bearing outside diameter. Prior maximum flange bearing outside diameter was 3.374" The set consists of the following individual main bearings:
- MB2035 (three)
- MB2559 (one)
- MB2620 flanged thrust (one)

These bearings are TRW "Micro" or steel backed babbit construction.

Part number 5024M is the Sealed Power/Federal Mogul number.

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[volaredon]

The engine he has is a 1983.