thislswon

iTrader: (5)

i have a rebuilt 4L60E with a 3500 TCI converter/B&M tranny cooler/corvette clutches and cervos/hardened sunshell and wider bands...tranny has been in almost a year with no problems at all(car has not been tuned after the converter was installed)...about 3 weeks ago i put mac mids and dynomax TD's on the car deleted AIR and EGR...every since then the car has been shifting weird....sometimes it will shift a lil later then what it should and sometimes it will act like it hits rev limiter but it doesnt actually hit it....it did it basically over night after the header swap...which makes no sense...ive heard that sometimes with anything over a 3000 converter you will need a tune because the car will shift funny...my question is it possible for it to just start acting like this and it just needs to be tuned....or does it sound like bad news for my 4L60..

Gilbert@Ace Racing

Many times after a header install the PCM will start reporting misfires. Also, the PCM could start reporting detonation. Have your Tuner take a look at it and see if that is the case.

I doubt seriously that there is an issue all of a sudden with your transmission.

Take a look at the fluid level and fluid condition. If something looks questionable get back to us.

g

thislswon

iTrader: (5)

ok...so i havent drove the car much since this problem finally took it to my tuner and he lowered the shfit MPH and shift RPM for each gear....problem still exists..its ver inconsistant though...sometimes it will hit rev on the 1-2 shift and someitmes it will hit on the 2-3...he lowered the points a little more and sometimes it would do it on the 1-2 shift and sometimes on the 2-3 shift

he says if he keeps lowering it its just going to short shift and run like a turd...i need help any experienced tranny guys..im going to post this over in the tuning section also..

Gilbert@Ace Racing

If the Tuner is satisfied that he has done his part to try and dial the unit in, then the only thing left to do is to Data Log the shift events. By Data Logging you will be able to determine when the shifts are actually being commanded vs. when they are actually occuring.

It is quite possible that indeed that your unit has suffered a setback. But... I still doubt it, mainly because of the comments about having changed the exhaust and then the symptoms appear and also the fact that there is an issue with the 1-2 and 2-3 upshifts. Ordinarily we find that the 1-2 shift will hit it's marks when the 2-3 will not.

If you would like to discuss it in greater detail do not hesitate to call me. I'm at the shop and will be for quite some time.

g

thislswon

iTrader: (5)

ok...the guy knows his stuff...hes built some pretty fast turbo/nitrous LS1's i just dont know how experienced of a tuner is...also he used HPtuners intead of EFILive...there is a guy on here who is considered to be one of the best efi live tuners in the country and he lives only a few hours away from me...if i cant get the issue resolved fairly quick im going to take it to him...the car shifts perfect at cruising-half and 3/4 throttle...no noises or anything and this started the very first time i took the car out after the exhasut install and has been doing it off and on every since..he said he has all the changes and passes he made on the car datalogged

another thing is it only does it from a dig/slow roll...anything over 25-mph it shifts fine...which is another thing that makes me think its a tuning issue since these cars are all electronic shift and it bases in part on wheel spin and it only acts up when the car jumps to high RPM while its spinning...thanx for the help

Gilbert@Ace Racing

No worries... I would indeed take it to the fellow you mentioned, or at least call and see if he might offer some insight as to why you have these symptoms.

Stay in touch... let us know hoe it works out for you.

g