4l60e 2-3 slipping shift

[vscapricetim]

Hey all,

I've started having a shift issue changing from 2nd into 3rd at WOT. It sort of slips and then changes. When it does change its a firm shift. If I'm not full throttle but revving up a bit it's a perfect shift. 1st into 2nd is perfect. As it does that the boost usually spikes at the same time.

Ill attach a log and my bin and maybe someone on here can see if it's a tune issue or mechanical issue. I've tried everything. Ose11p

Vs v8 statesman
Vortec v2 8psi
3.46 diff gears
Built 4l60e
3500rpm converter

Any help is muchly appreciated.

Cheers

[Wade]

Could be the adaptive shift settings. I’ve found the shift pressures are pretty good but the shift times are not. Simply lowering the adaptive shift times down to something similar to what holden used in the ls1’s makes a huge difference. Changing shift kph vs tps can also make a huge difference as well as tcc lockup. I’d recommend setting those tables before modifying any shift pressures as I’ve noticed changing shift kph vs tps has an impact on that. But yeah the adaptive shift times makes a huge difference. I could get my 4l60e shifting as if it had a shift kit just via lowering those shift times. I’m now running a transgo pro kit in mine and very happy. Drives fine a to b but progressively gets firmer the more you mash the peddle

[Wade]

here's a pdf file the1 put together about auto tuning. might help

[Wade]

and here's a look at the tune in my car at the moment for reference. ive spent a fair bit of time on the transmission

[Wade]

heres your bin with the vz ss adaptive shift times. i noticed in your tune, power mode the shift times are lower 2-3rd higher tps%. so you could try putting it in power shift and see if theres much difference. but yeah ive changed the actual tables in this bin file to show you the tables im talking about.

[immortality]

3rd gear is normally the weakest gear in the 4l60e, it may just be you've reached the mechanical limit.

I had issues with 3rd gear slippage in our VX L67, part of it was the wrong fluid but I also believe we were at the limit with almost double the factory boost etc. I ended up putting in a larger reverse boost valve ( Sonnax .490 IIRC).

[vscapricetim]

Thanks Wade,

I originally had 0.2 for desired shift time from 75-100% tps in all 3 gear changes but had changed them back yesterday to try something out but it didn't work.

When you say kph vs tps has a big impact on it how do you mean?

Immortality,

It is a built box and I'm running dex 6. Could it be I'm on the low side of being full? I'm about 5mm over the top of the hot cross hatching.

Cheers

[vscapricetim]

Oh and my power button doesn't work so I've ticked the normal mode on flag.

[immortality]

Thanks Wade,

I originally had 0.2 for desired shift time from 75-100% tps in all 3 gear changes but had changed them back yesterday to try something out but it didn't work.

When you say kph vs tps has a big impact on it how do you mean?

Immortality,

It is a built box and I'm running dex 6. Could it be I'm on the low side of being full? I'm about 5mm over the top of the hot cross hatching.

Cheers

I used to run DX6 but went back to DXIII.

If it's got too much fluid then it may aerate the fluid but you would see that on the dipstick when you check the fluid level.

[Wade]

Pretty sure these things are sensitive to being over filled. Found that out the hard way years ago.