Chevysil1500

Leaving selector in Drive Throttle to the floor.

RedXray

There are two different transmission shift tables one "normal" the other called "full throttle shift speed" Are you sure the tuner adjusted the correct table? You can try zeroing out the full throttle upshift MPH tables then the computer will default to the RPM table. If you still have an issue it could be the transmission itself. Is the converter a stock stall or a performance stall converter? I use the free "Bluecat" transmission software for HP Tuners to set up shift points and converter lock up... works very well setting up the shift schedule.

Chevysil1500

Thank you RedXray for the reply. I am not 100% sure the Tuner adjusted the correct table. As we walked through the motions and did some runs he would Lower mph and lower rpm to command shift at lower levels of both and this was not working. He stated, “I can keep lowering this but it seems more like a tranny problem”. That is all I know for sure he did. To me and from what I read on different forums it sure sounds like a problem with the tune.. I will have to contact the tuner and ask, than try to zero out the full throttle upshift MPH tables to see if that works .
It is stock stall.
Same Tuner did my old trans and it was set up great, I would hope he knows to do as you are suggesting. He is a very reputable tuner here in Southern California.
Additionally, this trans is still under a warranty so I did also consider bringing it back to the shop that installed it.
Thanks again for the suggestions, I’ll try this and go from there. I’ll post my results.

Chevysil1500

@RedXray Do you think the Tune I had on my old Tranny should work just the same on the new tranny? Both are 4l60e the new one is Supposedly Brand New Not Rebuilt.
Also, waiting to hear back from tuner in regards to recommendations you made last night.

MikeGyver

iTrader: (5)

I have always had my full throttle mph shifts zeroed so it shifts by rpm only. I don't understand the reason to have WOT shifts based on mph ever.
So anyway, it will aid your diagnosis after he zeros the mph WOT table.

Chevysil1500

Thank you MikeGyver . Spoke with Tuner and he indicated as we were trying to fix the issue he did zero mph on WOT and that is when he told me that he does not feel this is a Tune problem but more of a transmission problem.

Now, I do have the opportunity to bring it back to the same place I got it since the trans is under warranty so I will be doing so tomorrow.

(I do want to note that the company I bought this aftermarket warranty from is the one who provided the tranny. The shop I’m taking it to has been cordial and is working with me but stated “it’s possible they sent out a bad unit”..)

With all these symptoms any guess on what could be the issue?

It sucks because other than this WOT shift trouble it shifts fine, even if I slowly ease into WOT it shifts 1-2.. it’s only when I push throttle to the floor from a stop.

MaroonMonsterLS1

Setting the MPH to zero on WOT is not the right way to go about it. Your tuner sounds like he doesn't know **** about trans tuning

Chevysil1500

@MaroonMonsterLS1 Unfortunately I don’t know much about it. I prefer to do work myself that way if I f up at least I know what I did.
Truck is at the shop that installed the tranny, I’m nervous they are not 100% sure what they are doing either since after reading some other threads I checked fill level of trans fluid and noticed the shop way overfilled fluid.
Could the overfill cause this shift issue? I have read a few other guys with the 4l60e having this same issue. Fluid was at least an inch over max fill level. See photo.

.

MaroonMonsterLS1

Overfull not likely to cause it to bang limiter on 1-2

Post the tune and a log if you are able. That will be the best info

the 1-2 shift in a 4l60e is exceptionally easy.
It just brings the band on. The circuit in the VB is not overly complicated and not common to have big leaks.
Band adjustment and condition are important.
Servo type is important.
But the 1-2 is quite simple

Chevysil1500

@MaroonMonsterLS1 Wish I could post the tune but the tuners shop is about 2hrs away from me.
I have a corvette servo and The sonnax 4th installed.
This problem was happening before and after the servo install.
Hopefully the shop will be able to figure it out today..