To add to the list of issues with my newly built/installed 4L80E, it seems to increase shift firmness as it warms up. It is especially noticeable on the 1-2 shift. When cold (60-70F), the 1-2 is nice and crisp, when warm (90+F) the 1-2 is very firm and uncomfortable, this is under normal/light driving. I have modified the shift pressure tables to drop pressure when warm but it doesn't seem to help. Desired shift times are set to zero across the board. I do have some torque management for the 1-2 shift, it does seem to help soften the shift, but softens it at all temps, not just warm.

It's a 99 unit that I rebuilt with an HD2 shift kit, Sonnax boost valve, rollerized, and various billet parts and a full rebuilt kit. Also did the internal dual feed mod. I drilled the separator plate to "average" firmness for all gears.

Other issues that may or may not be related:
-No TCC lockup unless the line pressure is 150+psi
-Soft/delayed reverse engagement (I need to remove the reverse checkball)
-Very soft/slow 2-3 shift (I need to drill out the plate more or remove the 3rd checkball)

 

Colder, thicker fluid moves slower through the orifices, so the apply is going to be a little softer. Mine does the same thing.

 

I figured the warmer/thinner fluid would be able to fill the clutches faster. Makes sense.

Did you do tuning to soften it up while warm?

 

Yup mine does the same thing. I have mine tuned to be ideal when warm. I dont need a super crisp shift when its cold, and it warms up pretty damn fast.

 

Good to hear that it's normal. How much did you have to crank down the 1-2 base pressure in the tune? Stock was around 0.0 and I've backed it down to I think -6.0 without much change. EFI Live limits are -96 to 96 I believe.

Any torque management?

 

Dis you add in the little spring to the tcc valve that came with the converter?

 

The converter did not come with that spring, it's a Circle D multi-disk 2500-2800 stall.

I asked Chris about the spring a long time ago and he said he doesn't usually supply one unless it's a big power build looking to lockup at WOT. But that was in regards to a single-disk converter. I decided to go with a multi-disk, but he never asked me if I wanted the spring, I assumed it wasn't needed.

It won't lock even when I ground the solenoid, so it's an internal trans issue. If i command max pressure (~180psi in Drive) it will lockup no problem. If I'm at normal pressure and ground the solenoid nothing happens, but as I give it gas and the line pressure goes up the TCC will start to apply around ~130psi.

 

More or less. I don't really bother with tuning anything while its cold unless its having problems starting, e85, etc. I don't beat on stuff until its warm anyway.

 

I'm having this same problem after my 80e swap. The 1-2 shift is ridiculously hard at light/normal throttle. It feels like it's going to brake something do I haven't driven it much. Is there something I could of done wrong in the swap or install of the HD2 kit?

Truck is a ecsb 4x4 6.0 BB tuned with a circle d 3k convertor.

Not trying to hijack your thread, I just figured this would be a good place to put it since I can't find answers anywhere else.

Thanks.

 

If they are too firm, why not try to tune the pressure back at part throttle?