I have a 1999 Lesabre with a knocking motor. I also have a 2003 Bonneville SSEI with a healthy motor but blown trans and title issues. I cannot find any info on compatibility between a 99’ and 03’ motor and trans (going to rebuild trans, might do motor first and be gentle on the 99’ non-hd). Been hearing the trans might be a issue for the 99’. Any advice or knowledge on this?

You'd have to be reallllly nice to that transmission, especially if it has a lot of miles.

That'* if you get the combination to run in the first place. Are you prepared to deal with the electronics?

The 99’ has 120k. I have a heavy foot. Guess I’m testing my discipline lol. Hoping it will just be sensor swapping 😅

Have you ever tried this with any vehicle? You'll be lucky to get it to run right without a full donor.

Engine will swap over, but the PCM will need a L67 tune. Lots of shops out there that can do it, but I don't trust a single one. Better to use HPTuners because you can make on the spot corrections as need be.

No, the PCM will not swap over.

If you do swap an L67 to a non-HD trans, leave the */C belt off and drive it like its an L36. Yes, people have done it before. Sometimes on purpose, sometimes not.

With the engine swap does he swap intakes as well?

Intake? Like intake plenum? Or filter housing pipe?

When I did some swaps between older and newer engines of like the 5.7L GM we would swap out the intakes so that all the emission stuff was good to go.

yeah but the L67 and L36 are two different engines all together the only thing the same on the two is the block bottom end heads and all are two different heads the injectors are located back into a recess in the valve cover on the L67 for room for the super charger

See how the L67 has the Injector

moved into the head the L36 the injector is in intake