I only have about 800 miles on my truck now and it is my first diesel. But when I try to pass in traffic it seems to slow down a bit before it finally spools up and goes, is this normal? Is there a way to speed it up?

You posted in the LB7 but if you only have 800 miles I assume you have an LLY? If you don't know, check your serial #. If the 8th digit is 1 you have an LB7 if it is 2 you have an LLY.

Automatic or manual? Engine warm or cold? Loaded or unloaded and what is your altitude?

It's an LB7, automatic, unloaded and warm.

It shouldnt slow down any from your current speed. You need to let the truck break in first, power will increase as it breaks in.

Sounds like defuel. Pain in the but. You pull out to pass and floor it..the tranny downshifts.....and for a few seconds.....nothing happens. I found this very annoying. From this site, I found out the computer tells the truck to defuel ( or pause) to let the tranny shift.


Man could get himself hurt waiting on that thing to get moving. Nature of the beast. Hurry up get it broken in and go for some mods. The Edge Attitude box will get rid of most defuel for you. Maybe other power boxes as well. http://www.dieselplace.com/forum/smileys/Big Smile.gif

It shouldnt slow down any from your current speed. You need to let the truck break in first, power will increase as it breaks in.





I agree!





Break in is critical, seems like every 5,000 miles I put on her it just ran that much better.





36,000+ on mine now in less than 18 months. She runs better every day.





If it fall flat on its face, you may have a problem. Let the dealer earn his keep, let them know about it.

Mine sometimes acts lazy like that.

I'm not sure if it's the Allison not knowing what to do or what. Mine is juiced and I run around in levels 3 and 4, and at exactly 1500 rpm the thing acts like it's hesitating. Above 1500 it wants to take off like a house on fire, below that it kinda plays lazy. This is the rpm range where boost is just starting to come on.

If I just mash on the gas and drive like an idiot, it's fine. The tranny shifts well and locks well and feels like it's just rarin' to go, like a racehorse.

It's when I'm going through town and not racing from light to light that the torque converter stays unlocked and it just acts wimpy. If the gas pedal is at 1/3 or less a lot, it seems like it gets confused until you mash it. Sometimes it seems that the hesitation is more the tranny figuring out what you're trying to do than anything else.

I know it's annoying in town, but I bet if you engage tow/haul, it behaves better. Mine even behaves differently if I roll into the pedal hard (usually downshifts) semi-hard (builds boost and just goes) or softly (TC stays unlocked and feels mooshy).

I don't know if that makes any sense, but with mine, the harder I drive it, the better it behaves.

The other thing you might possibly want to try is replacing the fuel filter. If you search the threads, you'll find quite a bit of conversation on this topic. Some folks have found plugged filters, some have found air in the fuel system, etc.Edited by: nwpadmax

Ol' truckers called it "Building a Fire"; diesel fuel requires "Heat" to burn, turbos requires "Heat" to spool, drivers needs to know the difference's of "Gas" and "Diesel", (don't have to know how to spell.) If you want an instantious response, buy an 8.1, it doesn't do it either.


When you learn how to drive a diesel you will never go backwards.


Idahofox

Mine never downshifts...But on the highway I am usualy at 75-80mph...But it just usally whistle's louder and takes off..no lagg problems...