Stock:

-Gear Selector in D3 Position, and Transmission in 1st-Gear: Overrun Clutch = OFF.
-Gear Selector in D3 Position, and Transmission in 2nd-Gear: Overrun Clutch = OFF.
-Gear Selector in D3 Position, and Transmission in 3rd-Gear: Overrun Clutch = ON.

-Gear Selector in D2 Position, and Transmission in 1st-Gear: Overrun Clutch = ON.
-Gear Selector in D2 Position, and Transmission in 2nd-Gear: Overrun Clutch = ON.

-Gear Selector in D1 Position, and Transmission in 1st-Gear: Overrun Clutch = ON.

Sonnax HD 2-3 Valve:

-Gear Selector in D3 Position, and Transmission in 1st-Gear: Overrun Clutch = ON.
-Gear Selector in D3 Position, and Transmission in 2nd-Gear: Overrun Clutch = ON.
-Gear Selector in D3 Position, and Transmission in 3rd-Gear: Overrun Clutch = ON.

-Gear Selector in D2 Position, and Transmission in 1st-Gear: Overrun Clutch = ON.
-Gear Selector in D2 Position, and Transmission in 2nd-Gear: Overrun Clutch = ON.

-Gear Selector in D1 Position, and Transmission in 1st-Gear: Overrun Clutch = ON.

 

This is incorrect Vortec
I fixed it above in GREEN

 

Yup, I was not paying attention to my Copy And Pasting.
Grrr... More Coffee!

Thank you, I will correct that Post.

 

1, 2 and D is what I said if D = 3, not OD. I just listed the #s in the order on the shifter, 3-2-1, or D-2-1.

 

Does shifter position L2 skip using 1st gear or is that year/model specific? THANKS

 

My GM Tech Guide gives this quote for M2 position.
MANUAL SECOND - FIRST GEAR CONDITION IS ONLY AVAILABLE ON SOME MODELS. OTHERWISE, THIS CONDITION IS
ELECTRONICALLY PREVENTED

 

My TB is 50k miles now from this upgrades, and everything running perfect.

However, we did a copy paste to my friends TB, and hes car is moving forward thru all the gears. Even in Neutral and Reverse now.

We had a problem measuring the servo travel, so we carefully grinded the pin but i think it was not enough and it applies the 2-4 band all the time. Can this be my issue?

 

Thanks for the feedback on yours. Glad it's working well.
For the friends. If the band was applied in reverse and the reverse input was applied at the same time it would bind up. The forward clutch is on anytime the transmission is in forward gear ranges. If locked on mechanically it would bind in reverse as well.
What do you mean by we did a copy and paste?
When it is in neutral can you turn the driveshaft by hand both directions?
It may get more by starting a new thread of it own and more details.

 

No. The truck goes fordward.
I did everything as above. Blocked 3-2 downshifts and stuff.

No idea why the truck now goes forward in reverse and even in neutral.
i rechecked the servo, everything is fine.

 

When diagnosing something that we can't get a seat of the pants feel to. We ask questions that qualify a scenario.
So I asked if in neutral does the driveshaft turn both way's. If the 2-4 band is on or won't release. it will turn one direction but not the other. it is customary for the driveshaft to turn harder in one direction than the other. It should not be locked.
I also don't read through a whole post again to see what you have done. That's why i asked for more details and or a new thread to be started.
So did you just do a valvebody drop and repair? Did you do a Corvette servo upgrade? Did you pull the transmission and replace clutches, band, sprags and ETC?
So here is were my thoughts go..
Reverse is a manually selected range. The only electronic function is PCS and line rise. Park is also a manually selected range with linkage for the park pawl. If reverse is not applying and just goes forward. I'm in the mind set that the manual lever link did not get installed properly to the manual valve. To qualify this does the vehicle lunge forward and stop in park? Like something is keeping it from going.. Then putting it in reverse or neutral it still goes forward? Then back to park and it lunges and stops again? From there the manual valve link is not hooked up and the manual valve is stuck in the forward feed location.

 

will sure check that.
Im going on this thread, so nobody will have an issue when they read it.

Tranzman, i got a few questions :
when blocking both 3-2 valves, should i take out the springs or block it with springs compressed inside the valve?

I took the 3rd capsule out. Installed the superior directional valve. As i rememmber, on my tranny, i had to bang it in with a hammer. On friends tranny it just slides in with a finger. Is it okay?

 

Personally I use a 3/8" x .830 piece of brake tubing for the 3-2 Control valve. I move the spring to the front of the valve and put the tube inside. I use a similar 1/4"x.830 brake tubing when I block the 3-2 downshift valve.
The case is slightly different so that would make sense. Sonnax even states this in their installation instructions for the servo release capsule. See the notation in step 3.
https://www.sonnax.com/parts/2432-se...heck-valve-kit

 

You were so right my man.
My manual linkage was disconnected LOL (somehow slipped off when i put it in the manual valve.

 

Been there done that...

 

Dear Tranzman,

When using Superior K0136, is it okay if it just slides inside the bore where the capsule was? The K0136 slides in so easy, i can just take it out with 2 fingers.

This questions comes on because I feel his 3RD is no longer holds the gear on WOT and it wasnt like that before.
Can a bad servo travel make it slippy? You press WOT, and you feel like its not holding the gear 100%. It feels like 50% holds, 50% neutral. In WOT only. In part throttle shifts perfect and holds awesome. The 2-3 and 3-2 is perfect in part throttle in timing and holding the gear.

Config applied :

-Block both 3-2
-Use the spring of 3-2 into AFL Valve inside the current spring
-Block the 4th acum feed hole and keep the guts out
-Remove the Case Checkball
-Sonnax 2nd and 4th super servos
-Transgo 1-2 piston
-Sonnax pinless FWD piston
-O ringed end plug
-Directionall superior capsule for 3rd.
-Reverse and FWD Abuse plugs with new valves
-New separator plate with steel checkballs
-Fitzall TCC with canbus
-Central Valve Bodies 0.001 AFL and plug

Drilled Maroon's recommended orfices :

1-2 - .Stock
2-3 - .135
3-2 - .135-.
3-4 - ..110
BR - .101
FwD Clutch - .stock
Lo/Rev - .093
Rev - stock

I wanna fix that before he burns his 3/4. Thanks!

 

I don't use the Superior or the Sonnax 3rd accumulator fixes so I cannot say. I do know that if using the Superior replacement requires you to remove the OE check-ball capsule. If there is a leak around the replacement part it will allow the band to stay partially applied. That could be your feeling. Is there an O-ring for the part if it fits loose? Sonnax supplies an O-ring for theirs on a loose fit.
3-4 oil turns into 3rd accumulator oil.
This is from my GM tech guide.
Step 1c
#4 and #2 Ball Check Valves: 3-4 signal fluid unseats the 3-4 clutch exhaust ball check valve (#4) and enters the 3-4 clutch fluid circuit. 3-4 clutch fluid unseats the 3rd accumulator ball check valve (#2) and enters the 3rd accumulator fluid circuit.
Everything else looks good.

 

I would try the trick with a tube cutter and put some ridges where the valve touches the bore. also could carefully use some green loctite and let it cure for a full 24 hours.

 

will sure do that!
Is there any reason, on my 08 tranny, i had to bang it in slightly with a hammer, on his 08 tranny it just slipled in with a finger?

The loctite part goes to the case side right?

Thanks Tayto!

 

every one ive installed has had resistance going in. either the part is undersized or the bore in the case is oversized/damaged. i would put the loctite on both parts where needed. you will need to blow through the valve with compressed air after to make sure none gets in. dont blow air around the outside as you'll push the loctite out between the parts. i wouldn't go crazy on amount applied most of it will get pushed out