06 LLY to LBZ reprogram?

[Kansas T]

I would like to update my 06 LLY to the LBZ OS. From what I've read, hptuners can't do this for a diesel, so I'll have to do it at the dealership. I work for a GM dealer, so that's not a problem. The problem is that in order to select an LBZ program with the GM software, I need to use a different VIN number from a truck with an LBZ. Will switching VIN's on my ecm and tcm cause any other problems? BCM or security issues? Will all the controllers need the VIN changed?

[mecanicman]

06 lly and lbz use the same o/s. No need to change. Just open up your file, download and open in compare a stock lbz file, copy across differences, and your done. I believe the engines are physically the same, but there was some ducting differences you may want to look into.

[Kansas T]

Every LBZ file I found in the repository showed a different OS than my LLY, so that's why I thought they were different. I also noticed some of the tables had different ranges than mine, which made a quick copy/paste of a table a lot of work. I updated all the available tables to LBZ specs last summer and have been driving it ever since, but I was told at that time that hptuners doesn't show all the changes or tables. I don't know for sure, I'm just a novice tuner. The reason I was hoping for an update and the reason I made the original changes is because the truck get poor fuel economy. Its got stock sized tires and magnaflow turboback exhaust, but still only gets 16mpg cruising @65 mph and taking it easy getting up to speed. This is hand calculated. Above 65mph the mileage is worse. I made some small increases to timing and reductions to boost in the cruise areas and have yet to see an improvement. I also redid the timing tables with the timing calculator and didn't see any improvements in economy. I did get a power increase though. Because I'm using winter fuel now I can't get an accurate check of the economy, so there's no sense making any changes. Maybe a quick review of my tune would help pinpoint any problem areas?

read10-11-14.hpt

[mecanicman]

Your file is a different o/s then others I have seen, but when I open it with a stock 06 lbz all the tables are the same. Not sure if you didn't use a stock lbz or if its stuff you modified, but lots of tables different. Your boost table is higher then stock lbz, and to reduce it you kinda went the wrong way. Log your truck driving with pids required to populate the desired boost histogram and you will see what I mean.

[Kansas T]

Good catch, this is no longer stock LBZ tuning. I drove with the stock LBZ programming several months before making the changes for additional power that are in the tune I posted. I was having trouble with high exhaust temps while towing (before I installed my exhaust system), so I added a little boost. I'll have to double check things when I get home to see what I did. I thought I lowered the boost in the cruise ranges and raised it in the high load ranges, but maybe not. The table differences were only on a few tables in the upper rpm ranges. I'll check which ones tonight.

[Kansas T]

The LLY tune lists 3300 rpm, but the LBZ tune lists 3250 instead. Not much difference, but it made a direct copy a little more difficult. I double checked the boost tables and its set up like I thought. I'll try the histogram and see what it shows.