I'm new to this foruma nd to the duramax. Havent been around one much but would like to learn more about them. Proably a stupid question to ya'll but what the difference between the LB7 and the LLY engines? Thanks

Real simple the LLY went from 300hp to 310hp and torque went from 520ftlb to 590ftlb. This was done with a new turbo set up. There were also some changes to the tranny for the gain but the torque is still 520 in 1st and 5th I believe. One other thing is that the LLY meets EPA requirements and has a Cat on it along with egr.





Hope that helps





Tom

Welcome ltfox. There are no stupid questions. The only stupid ones are the ones that aren't asked. The LLY has a variable vane turbocharger which gives it a wider range of RPMs. The fuel system has also been changed to alow easier access to the injectors. The LLY also has a cat. Last but not least is performance. It has more Torque and more HP.

LB7 was in production from 2001 through mid 2004. LLY Went into production around January 1 this year. Easiest way to tell the difference is either to look at the VIN 8th digit. LB7 8th digit is a 1 LLY 8th digit is a 2 or look under the hood, if you can see injectors its an LLY if you cant its an LB7. I've also heard that the HP/TQ gains with the LLY are only available if you have an Allison, can anyone verify this?

ltfox,


Welcome to the forum...http://www.dieselplace.com/forum/smileys/Approve.gif


There's lots of info here about the two different engines including both facts and speculation. Some reports, but since there are still not many aftermarket items available for the LLY, you won't find much about those.


Try a few searches to pick up on some of the many posts about them, and it'll get you used to how the search engine works.


In the meantime, there is a really good write up about the LLY on another forum. Be aware that this was written before the LLY was actually released, and the 310hp/590ftlbs torque is what the LLY is actually rated at:


http://www.thedieselpage.com/duramax/lly2004.htm


Give it a look and I'm sure quite a few of your initial questions will be answered...http://www.dieselplace.com/forum/smileys/Geek.gifEdited by: Zeeb