GEN 5 GM LT THRUST BEARING UPGRADE
The new Gen 5 GM direct injected V-8’s only come with a half thrust bearing in the main bearing set. The GM coated bearings are a very nice bearing if a Bi-Metal Aluminum bearing is ok for the application. So far on the sets that I’ve checked, the sizing is amazingly consistent from shell to shell, and from one set to another. The problem is, on a high performance application making big power this single thrust is not ideal, in my opinion. The good news is GM did cut the thrust face on the cap side, and the upper shell does fit in the cap. The GM part number for just the #3 upper is 12618105 which you can order individually from GM. There are no aftermarket coated bearings available at this time that I could find. You can use a Gen 3 or Gen 4 LS main bearing set with minor modification. The alignment tang locations are different so you would need to grind new location grooves into the block and cap to get them to work or just remove the tangs altogether. This is easily done with a file. The thrust bearing is the only one that is different.

Jake Sampson
Sampson Race Engines
Inver Grove Heights, MN
February, 2020