My factory spring looked more similar to the spring on the far right but honestly I can't remember what color. The blue one looks like the factory spring I pulled from the 4th accumulator piston. The transgo yellow spring that replaced the blue one for the 4th accumulator piston was shorter than the blue one.

Sorry for the late reply, been busy with work.

 

So what all do you have in your trans offroadrider? I've got a 2004 Silverado 4.8/4l60e. I'm having some issues I believe with the Tcc. So when I drop the pan I want to put some goodies in there. I'm not pulling the trans I hope. Thanks

 

Transgo SK 4l60e kit, new OEM separator plate, Sonnax Torlon .250" check ba**s, corvette servo, sonnax pinless 2nd and 4th accumulator pistons, and the sonnax pinless forward accumulator piston and a bottle of Lubegard Red additive.

My issue turned out not to be the actual TCC valve, my trans still jumps in and out of TCC lockup. I took my truck to a reputable trans shop in my area and they said it isn't the trans, but something electrical on the chassis causing it to fall out of lockup. It isn't my TPS, but there is much more to check out. I have some searching to do.

That said, I do like the changes I have made to the trans. The 1-2 shift is nice at light and part throttle, and at WOT it is firm enough to squeak my serpentine belt due to the worn out tensioner. The rest of the shifts are firmer but not harsh, honestly they could be firmed up a tad more but are better than before.

If I were to install this kit again, I would probably use the white spring for the accumulator instead of the blue one, or at least installed the special transgo pin so it can be changed without pulling the valve body.

If you install the transgo SK kit I would not drill out the 2nd gear oil feed hole in the separator plate. Mine from the factory was about .063 and I kept it at that size. All the other feed holes I drilled out to the larger spec on the instructions.

 

Quick question. Im reading that many of you went to this pinless aluminum piston. I have also read ( not on this thread) that you can not tune a trans that does not have this pin. ???? I dont understand that but thats what I have read about the 4L60E 4L65E 4L70E. I still have the plastic one in both and am at a point to were I am having a few problems and am going to have to change them in both units. I have one of each minus the 65E. The 60E in a 2001 GMC Sierra 1500 and a 2007 Silverado MAX with the 6.0 has a 4L70E in it. I have a Diablo I1000 that worked great for what it is on the 2001. Im just afraid Im going to loose the tune or not be able to tune the trans and change the shift points because that added a tremendous amount of UMPH...that stands for get up and go. thanks

 

I don't see how the pin would affect tuning.
Some performance trans builders only use the pinless ones and I imagine they wouldn't be doing so if it inhibited tuning.