2002 LB7 over-rev in 4th gear

[BigTexas68]

What would cause my truck to over rev in 4th gear? I let off the pedal at 3700 rpms.
I think it has something to do with the torque tables that's been giving a hard time with this big tune. If I leave the tables stock or close to it I dont have a problem. I can post my tunefile if anybody cares to take a look at it.
Thanks,
Thomas

[LB72004]

the throttle base injection, TLIQ and base torque are all connected/related to each other. leave the tables stock unless you know what you are doing. no need to change the torque table unless you are fixing transmission shifting issues. the ECM doesn't know what torque it is making, the numbers are just the calculated torque values based on the stock mm3 pulse width. when increasing HP the ECM doesn't know the torque has gone up. the base torque wont limit anything.

unless you know how to adjust it, leave it stock. if you are having shifting problems, do some logging and find the areas (RPM, mm3, throttle mm3, etc) that the hiccups occur and make the necessary changes only to the needed cells in the TLIQ & base torque

also, start small. change only a few cells at a time a little at a time. see how it runs make more small changes, rinse and repeat. doing this will teach you what does what and will cause less problems. can take along time though, but is worth it.

check this out: http://forum.efilive.com/showthread....ome-such-thing

[BigTexas68]

the throttle base injection, TLIQ and base torque are all connected/related to each other. leave the tables stock unless you know what you are doing. no need to change the torque table unless you are fixing transmission shifting issues. the ECM doesn't know what torque it is making, the numbers are just the calculated torque values based on the stock mm3 pulse width. when increasing HP the ECM doesn't know the torque has gone up. the base torque wont limit anything.

unless you know how to adjust it, leave it stock. if you are having shifting problems, do some logging and find the areas (RPM, mm3, throttle mm3, etc) that the hiccups occur and make the necessary changes only to the needed cells in the TLIQ & base torque

also, start small. change only a few cells at a time a little at a time. see how it runs make more small changes, rinse and repeat. doing this will teach you what does what and will cause less problems. can take along time though, but is worth it.

check this out: http://forum.efilive.com/showthread....ome-such-thing

I have been making some small adjustments and have the trans shitfing pretty good. It seems like if the base torque is increased it firms up the shifts. My main concern was the over-revving in 4th gear. I have seen as high as 3800 rpms in 4th gear on my logs and that really concerns me. After making some adjustment to the TLIQ & base torque I don't have the issue any more.
Why would it over-rev if the TCM shift rpms haven't been changed?

[LB72004]

increasing the base torque will cause less of a defeul during shifts. this will cause the transmission to shift faster. go too fast and it will start to act funny. it will hang between shifts, bang or even tie up. if it hangs and the ECM is not defeuling enough then the RPMs will go up instead of down during the shift.

remember, you cant change one table (base torque, TLIQ) with out affecting the other. and it my be necessary to input new torque values into the transmission's TCM so it knows what it is working with.

try and make the TLIQ match the TBIQ.

do this by following the mm3 & RPMs in the TBIQ to the base torque. then find the corresponding torque value and RPM, and match this up in the TLIQ.

the tables wont show all of the cells as there are numbers in between them so ether hand calculate it or use the excel sheet from the above link.

this will make your transmission shift properly and allow you to have high mm3 numbers

[BigTexas68]

Thanks for your help. I will give the spread sheet a try, if its like the timing calculator it will be a great tool.