so I was rollin on the interstate today and punched it, it dropped into second and pulled up to the rev limiter and bounced for a not so normal amount of time before shifting into 3rd..what could it be? shift solenoid going bad? tuning problem? PLease help.

 

Could be either or the beginings of a mechanical problem. First how many miles are on the trans? What is the fluild condition and is it full ?

 

Well, there are many, many threads regarding this same subject! LoL.

It could easily be a Tuning issue. But usually only if something in the combination has been changed recently.

Otherwise, it will most likely be determined to be excessive clearinace in the 3/4 clutch pack.

If you would like to discuss it in detail feel free to give me a call. I help guys with this very issue several times each week!

Good Luck,

g

 

well, I just changed the rear end gears to 3.73 from 3.23. I have never had this problem before. It only does it when I floor it (100%TPS) and it only does it from 2-3 (of course I havent taken it faster to see if it does it 3-4 high RPM...be going pretty fast there lol) I did change the final ratio with HP Tuner and it recalibrated the trans tables... I also just recently put long tube headers on with off road Y. I am thinking it could be gettin up there quick and maybe I need to change the fuel cutoff to a little higher...hmmmm...
the fluid is good...the trans only has about 10-15K if that. the clutch pack you are talking about is the Zpack...I think its setup properly...I hope it isnt internal...

 

I would try making a little more room between the comanded shift time and rev limiter. Either by lowering the shift point a little or raising the rev limiter a little.

 

Thank you guys! I am gonna try that right now and get back to ya tonight I set up a tune last night...Im gonna go flash it and run it

 

I've had no success in tuning this issue out, its making me consider a T56 swap. 3 different trannys and still no luck. I went from a stock 115k mile unit, to a stock 6k mile unit to a brand new built unit and still have this, with multiple changes to the tune. I've even experimented by setting the WOT 2-3 shift at 5000rpm and it still does it. Maybe it has to do with me running a speed-density tune?

 

Though I dont know that much about tuning , I have see other post with people having a similar issue with the speed density tune as I remember seeing them mention that,

Have you looked at the data stream to see if indeed the shifts being commanded, I know in the snap on scanner you have a place that says "actual gear". I have seen a couple instances where even though the tuning was set for a certain rpm and speed yet the PCM comanded at a different time, Also I have noted from some other post its very improtant you bring down not only the RPM but the MPH also when changing shift points

 

I'll give that a try, I'm getting really tired of the automatic not being able to drive properly.

 

this sounds weird...but my o2 sensors were bad and made my ses light come on,,.....it did this same thing then that it did to you...and felt much slower

 

Good luck and if you fail there we actually have a box I may can loan you that allows you to become the PCM and comand the shifts, This will bypass the pcm and allow you to determine one way or the other wether its a trans or Tuning issue,
Again good luck and keep us posted ,

 

well I tweaked mine a little and it now shifts at a lower RPM...seems like its a tuning issue and it might take some TLC to get it just right...Thanks again Gilbert!

 

You bet. Glad I could help to make a difference.

Be sure to give me a shout if you need help dialing it in... but remember it's going to require patience.

g

 

Update: I found something that might be causing this for me anyways, possibly other speed-density guys. My TPS was set to go WOT at 92% open, plus the bumpstop mod. When I set it up to 99% it stopped doing it, so I'm guessing the tune can't compensate for the extra air if there is such a huge gap between WOT and where the throttle plate actually stops opening. Not really sure why this might be, but it seems to be fixed now anyways.

 

Very cool glad to see you have got it now. I will also make note of the change you made to possibly help people in the future

 

I'm happy I found it but I've already started picking up the components for the 6spd swap, after I found myself pawing a non-existent clutch pedal to downshift the other night I decided it was time.