4l60e 2-3 slipping shift

[Wade]

Just a thought. Could try retarding ignition timing up around redline or right where it’s shifting to reduce torque which might help.

[immortality]

Just having a look at the data log. Force motor current stays constant through the 2-3 gear change so line pressure should be at maximum (with no transient modifications).

Trans_slip_forcemotorcurrent.png

Have you tried manually shifting 2-3 and seeing if it behaves the same?

[immortality]

Also, looking at the rate of acceleration Vs engine RPM it looks like trans slip increases as the rate of RPM increase goes up but there isn't a corresponding increase in rate for road speed.

[vp304]

Once you start making enough torque they start to slow change on the 2-3 and will quite often smack the limiter a couple times before shifting even the t700r4 with a full manual shift kit does it at around 10-12psi of boost

Yeah, that sounds like mine.
1-2 from commanded shift until minimum rpm point in 2nd (start of accel in that gear) approx 1sec.
2-3 from commanded shift until minimum rpm point in 3rd, approx 2.5seconds.
Lazy!!

My vr 4l60e does exactly the same as this tho i havnt had enough time to log it to see whats going on tune wise

[Wade]

Yeah looks like it’s slipping all the way through 3rd

[vscapricetim]

So manually shift shifter 1 2 3 under wot? Does that then use the manual tables?

I did notice in a log yesterday that it's telling me cruise control is active.... don't know how that's possible as its not connected....

Ill post a log of a worse shift than that one.

[immortality]

Yeah looks like it’s slipping all the way through 3rd

Yes, it doesn't look like 3rd actually fully engages.

So manually shift shifter 1 2 3 under wot? Does that then use the manual tables?

I did notice in a log yesterday that it's telling me cruise control is active.... don't know how that's possible as its not connected....

Ill post a log of a worse shift than that one.

On this one it looks like it starts to pull down the RPM going into 3rd but then flares again.

Trans_slip_forcemotorcurrent1.png

What fluid did your transmission builder recommend? Do you know what when into the build?

Dex 6 is slipperier than DEX III. Dex6 is also slightly thinner than Dex III. I know the manufacturers say it is backwards compatible but I disagree.

[vscapricetim]

I bought it 2nd hand from a forum member here and he said to run dex6. That's what he was using.

Box is fitted with beast shell billet sungear upgraded servo modified valve body extra clutches and 5 pinion planetary is what he listed. I'll see if he has the build list.

[immortality]

I'd try changing to Dex III first.

[vscapricetim]

Will do, ya need to flush dex 6 out completely or is ok to mix and match? I have a drain plug so it'd make it alot easier.