improving mpgs?

[The Daver]

I am not aware of said 411 swap what is it???

 

[6chevy9]

it is a pcm swap, theres alot of reading involved but worth it here is the link http://www.gmt400.com/forum/showthread.php?338-99-LS1-PCM-swap-into-OBS-GMT400-trucks-SUV-s that should work but if not its under engine performance and matinence, and 99 + ls1 pcm swap, follow all the links that are posted in that thread and read everything you can handle. afterwards you will be amazed and want to do the swap real bad. i havnt done it myself yet but im getting really close and plan to do it.

 

[CodyB]

Well, with my 130xxx mile 96Vortec I had a timing chain worn out nearly to the point of it getting into the timing cover, I swapped it out last night, but I could immediately tell a difference that the chain was retarding my cam. You might want to think about that too since it was about $40 for that plus an oil change ~$25 (maybe an oil pan gasket ~$25, I reccomend Felpro blue one piece) and antifreeze (about 1 gallon of strait antifreeze plus 1 gal of water). If you get the seal kit from felpro ~$40 that should also kill most if not all of your oil leak from the front side (About $150 total, but worth it for me). I had the stuff to do the rear main and front pump seal as well, but opted to do those another night due to time constraints of my buddy and I. Im gonna have just about all the seals on this motor replaced before long...

 

[6chevy9]

i did mine a long time ago. but only because i swapped the motor