PPE Xcellerator ?

**BigRedChevy** · 12-13-2007, 04:59 PM

Since i installed the xcellerator if i really get after it the truck seems like its not shifting when it should. I have it set on level 3 and it don't feel like the tranny is slipping but it bumps the rev limiter for a split second before it shifts. Is this normal with the extra power?

**TYREBOYZ_DEMAXIN** · 12-13-2007, 05:20 PM

how many miles has it been since you downloaded the tune and i do know my Allison shifts nicer once i had a 100 miles or so on a tune..

**Maverick684** · 12-13-2007, 05:22 PM

Up to level three the Xcelerator will defuel for shifts which might explain the problem. Since you have the bullydog shift enhancer you might try reprogramming the truck on level 4 and see if that makes any difference. I have had mine on for about a month and my tranny acts a little weird when shifting under full throttle also. Probably just too much power for it. Just some thoughts.

**BigRedChevy** · 12-13-2007, 05:23 PM

I have only put about 75 miles on it. It shifts smooth. It just feels like it's not trying to shift until it is too late. Goes into the next gear grabs and starts pulling again just fine.

Thanks for the help guys

**aggar** · 12-13-2007, 09:33 PM

It's defueling. Mine does it and mine's been in mine for 6 months. Just watch the 4-5 shift.

**TYREBOYZ_DEMAXIN** · 12-14-2007, 06:06 AM

my LBZ runnin the big tune and it doesn't do that allthough it does defuel between shifts but it doesn't jump RPM's at shift points but if i remeber right back when the our LLY had the stock tranny it did something like that and it ran like that for almost 40K miles.