tcc lock up during shift.

[02denali]

do i need to leave this on. i have a vig 2800 multi disc lock up stall. or does it make a difference.

[12secSS]

I wouldn't, I don't have it enable in my 2001 SS. I once did and could not notice a difference, so I turned it back off.

[mustbbrent]

do i need to leave this on. i have a vig 2800 multi disc lock up stall. or does it make a difference.

I think it depends upon whether you lock the TCC before you get to top gear. I have a tall stall for this heavy truck you've seen my truck, so especially when I am in tow/haul mode, I lock the TCC in 2nd gear and desire it to stay locked always. To do that, I use the lock up during shift to lock the TCC as the tranny goes into the next gear and keep it locked as I accel towards the top gears.

[12secSS]

Selecting "TCC Lock Up During Shift" on my 2001 Camaro SS did noit do anything. This was tried out when I had my 3rd gear TCC apply speeds lower than my 4th gear TCC apply speeds. My trans would shift into 3rd then lock, then shift into 4th and unlocking then lock after the speed was reached. I had to subsequently raise my TCC apply speeds for 3rd gear (one MPH higher than 4th gear) to resolve this issue. GM had it setup similarly. I don't know if it only works with tow haul mode, but I will find out when I make changes to my Sierra. So it appears that F-bodies do not benefit from this on/off option.

[MSCLCAR]

I think it only applies to WOT shifts. I changed mine to ON & it feels like it shifts a WHOLE lot harder now when I have the long pedal planted! But under normal driving conditions, it seems to have changed nothing, like 12secSS said.

[12secSS]

I actually logged the TCC mode yesterday and at WOT it will not engage if your TCC apply speed is set high nor will it keep the TCC locked during a shift. The "Keep TCC Locked During Shift" works only when the upper gears have the TCC apply speed lower than the lower gears. Then it will keep it locked, otherwise the VCM will release the TCC during a shift, then reapply it (if the speed is met for apply).

[DanaliHD]

why would you want it locked? the only time mine locks is at cruising speeds in 4th gear and it feels like ass.

[MSCLCAR]

why would you want it locked? the only time mine locks is at cruising speeds in 4th gear and it feels like ass.

For racing purposes. It's like power shifting a 6sp. If your goal is to run AS FAST AS YOU CAN, why lift off the gas? To save parts of course. But my driveline is designed to be hit HARD, so I want it locked. I only have a 3200 stall, so I'm not likely to fall below that when I shift at 6500, so I don't "need" it to unlock (& flash higher).

[12secSS]

You don't want to be using the TCC during 1/4 mile passes or racing from a roll. The is the best way to kill the clutch, it is designed for economy and not for racing.

Reason for locking the TCC during shifts is for towing duty mainly, hence why F-Bodies didn't have it programmed that way ... and because the stock TCC can't handle high rpm abuse like that. It is a very small contact patch as compared to a manual's clutch liner.

[MSCLCAR]

Well, when you're right, you're right.....this just in from Mike @ Yank

....you do not want to lock the converter when racing as it will slow down the car you will loose all of the extra torque the converter will give you.....

I apologise for my stupidty. I was certainly misinformed about this!

Thanks for saying something 12secSS.

[02denali]

ok when i get my truck back i will turn that off since i do not tow a damn thing. i think my vig can handle it