Any difference in cranks?

[JeepSJ]

Between the late 90's GM engines and the later Navistar based engines? What about connecting rods?

[trbankii]

Pretty good discussion of the AMG blocks in the sticky: http://www.thedieselpageforums.com/tdpforum/showthread.php?t=31362

[JeepSJ]

I'm talking Navistar 509 block, not the P400.

[trbankii]

The Navistar 506 blocks are the AMG blocks. ;)

I think you’re getting the 599 (earlier GM, not Navistar) blocks mixed up with the 506 blocks - only the 506 blocks with a date code after 2000 were made by Navistar.

AMG/GEP 506 Navistar Longblock ID: http://www.thedieselpageforums.com/tdpforum/showthread.php?t=30041

[Robyn]

They will interchange.
They use the same bearings

Even the Forged crank from AMG will drop right in.
The Scat cranks fit as well.
The rods are all the same too

The changes were in the metallurgy and some internal dimensions of the block, but the basics of the crank are the same.

The old GM cranks should in my opinion be considered sketchy at best.

If you are building a fresh engine with a good solid AMG block I would not stick in an old GM crank.

Unless it was a new old stock it's going to have a lot of time on it and even if it shows good with a magnaflux test, it's a cast iron piece and could be at the end of it's life.

If the budget will handle it, get a fresh forged crank.

Just sayin.

I used a Scat crank in the last build I did.

[JeepSJ]

The Navistar 506 blocks are the AMG blocks. ;)

I think you’re getting the 599 (earlier GM, not Navistar) blocks mixed up with the 506 blocks - only the 506 blocks with a date code after 2000 were made by Navistar.

AMG/GEP 506 Navistar Longblock ID: http://www.thedieselpageforums.com/tdpforum/showthread.php?t=30041

Sorry, meant 506. This is a 2009 Navistar 506 block, but NOT the P400 that has the girdle section for the mains.