Thread: Install Success
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Old Fri, June 18th, 2010, 12:52 PM
BigSur BigSur is offline
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Quote:
Originally Posted by JackandJanet View Post
It's fine to bring it up here, but the guys at f150online might have some ideas too.

It COULD be that your Torque Converter is locking too soon or is locked as you do the 1-2 upshift. This is one of the things you can monitor on the Gryphon and CS/CTS platforms. If you see a little "padlock" symbol next to the "Commanded" gear number, the TC is locked. That would tend to make the shift feel harder. The TC lock point is governed by both speed and power demand, so if the power demand is low, it may be locking prematurely.

I've felt what you describe at times pulling up a "mild" hill with a trailer and the TC locks in 3rd. Then, when it upshifts to 4th, it does so without unlocking and the shift is quite "harsh". I've also felt something like this at times when at a lower speed where I've come off the gas and then I step down on the pedal again, but not too hard - it feels like the transmission abruptly drops into a lower gear and there's a hard "clunk" and "lurch".

In Custom Options, you can delay the TC locking for any of the gears, by ADDING to the "zero" value that you'll see there. You can change it +/-2 in 1st, +/-3 in 2nd, +/-5 in 3rd and +/-10 in 4th I think. If you put in negative values, it causes the TC to lock sooner and stay locked longer as speed decreases. You can also adjust the part throttle up/downshifts the same way.

You might try playing with those settings. I've cranked my TC lock/unlock and part throttle up/downshift as far negative as they'll go on my non-towing tune, because I want the engine at the lowest possible RPM for cruising. The WOT power is still there though.

This is an example of what I was talking about when I said to drive it a while to see if there's anything you DON'T like. If you were to decrease your upshift/downshift 1-2 settings and increase the TC lock/unlock settings for 1st and possibly 2nd gear, it might eliminate what you are feeling.

- Jack
Very good info Jack, thank you. I'll probably have to read what you've wrote 2 or 3 times to fully understand before I would feel even remotely comfortable with adjusting settings. However, your description almost hits dead on b/c I too have noticed the thump when letting off the pedal and then stepping back into it at the wrong time or close to a shift. In short, I think I'm shifting too soon from 1 to 2. I'd like to increase the speed and/or rpms slightly before that shift occurs, as it always shifts better when under those conditions.

I will research this more and will most likely utilize your advice and play with the subject settings once comfortable. Thanks again.