Which 6.0 block?
The only thing with the '99 and '00 6.0L Short Block is the crankshafts rear main flange is longer...
Otherwise you have to use a TH400, 700R4, or 4L80E with the '99 and '00 Crankshaft
It is the crankshaft that is different on the 99-00 6.0L
As far as the early crankshafts (99-00) goes, the rear main flange area was 1.25 wide or thick how ever you want to describe it and have a Casting number 12552215
The Noramal size ones for 01 - up should measure approx .860 wide/thick and have a Casting number 12552216
Here is some info with pictures...
http://www.enginebuildermag.com/Arti...ankshafts.aspx
5.3L, 5.7 LS1 and 6.0L are the same exact crank... They are how ever Balanced differently for there specific set up. A true LS1 crank also had a 1 Inch hole gundrilled through the center of the mains to help save weight. The all share the same Casting number 12552216
Here is a side by side crank picture.
https://ls1tech.com/forums/876185-post19.html
BTW those early engines came with heaveir Iron heads... There exactally the same as the 01-up 317's only they were made of Iron.
Either way, putting a different crankshaft in a '99 or '00 block will solve the problem...when I say different crankshaft, I mean one from an LSx, LQ9, or newer LQ4.
Where can we find the cheapest LS1 crank that you guys would recommend?
I figured I would reply in this thread, since it is halfway related to this thread anyway. Thanks!
Some people are buying cranks from a 5.3L or a 6.0L thinking they are getting an actual LS1 crank when in fact they are not. They even pay more for an LS1 crank. For some reason people also think That an LS1 crank Might be better when in fact it is really no different from it's truck counter part. Other then the 1 inch Hole through the center. My thought would be that the gundrilled crank would actually be weaker in a high HP situation.






