How To Mount a 6.0 Liter LS Engine to an Older GM TH350 Transmission

YouTuber BEETEROLDS needed to mount an older GM TH350 automatic transmission to a 6.0 Liter LS Engine…

Editor’s Note: While not the finest video production ever (the creator was testing a new SONY Handy Cam), BEETEROLDS demonstrates how to get the transmission and torque converter bolted up to the engine without an issue, and No Adapter Required!

TH350 To An LS Engine ~ Early Vs Late Flexplate Comparison

I have made videos before describing how to mount an old transmission to an LS engine — but I’ve never had both different flexplates side by side.

On the early 99-00 4.8s and 6.0s they use a longer crankshaft and flat flex plate to work with the 4l80e. With engines that used the 4L60e, GM used the dished flexplate which required the step bushing style spacer.

Fortunately for what I am doing (above) with the 6.0 I need no spacer. The only mod I need to make is to oval out the mounting holes on the factory flexplate.