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View Full Version : Controlling downshift questions....


Big Calo
Tue, April 12th, 2011, 03:01 PM
My dad has a 2010 f-150 with a 5.4L engine. It has a 6" lift with 35" tires. He has already put 4.10 rearend gears in and it has the cruising RPM about where he wants it.

The problem is that when it starts to pull a hill it downshifts really wierd. It will lug and lug then all the sudden downshift twice and just scream up the hill. It makes it really frustrating to drive when it does this. Most of the time just one well placed downshift would do the job.

Is there any type of programmer that is offered that will maybe just give more power, or at least be able to help out on the trans shifting?

ticopowell
Wed, April 13th, 2011, 12:14 AM
The Gryphon CS or CTS will only affect engine performance on a 2010 so either one would be just fine with your dad's truck. My dad has a 2010 as well but he doesnt have a lift or tires so ive not noticed any problem.

Jackpine
Wed, April 13th, 2011, 10:42 AM
Calo, your Dad may be experiencing something that other users of that model year truck don't like, and it seems to be tied in to the new, 6-speed transmission. I think a 4.10 rear end with 35" tires is about equivalent to my 3.73 gears and OEM tires, so I imagine it's geared properly.

As Tico said, the Edge/Gryphon for that model year does not program the transmission, yet, so I doubt he'd see anything MUCH different with it. The engine would produce more power though, and that might be enough to fix things somewhat.

The problem is, he is getting a "part throttle" downshift that is controlled by both engine speed and throttle position. (It's really kind of a "load" commanded shift.) The TCM "sees" a need to drop down two gears to provide the needed power to get up the hill. I see this once in a while in my truck too, especially when towing. 3rd gear isn't quite enough, so it drops into 2nd, which is "way overpowered" for the task. I kind of wish my 3rd gear had a slightly higher ratio than 1:1. It seems like there's not enough difference between it and 4th.

Since I can change the part throttle shift characteristics in my model year, I've corrected this tendency to shift too quickly a bit, but you don't have that option in a 09+ truck.

It's possible that Bill can write a program for the X3 that will adjust the transmission though. You'll have to ask him.

- Jack

shotgun
Wed, April 13th, 2011, 12:01 PM
Yeah, but us 09-10 owners (with the CS and CTS) have a fancy Maintenance Manager!

Oh wait, so does everyone else with a CS or CTS.

:rolleyes:

Over 6 months and still no update from Edge on the 09-10 TCM...

Big Calo
Mon, April 18th, 2011, 02:31 PM
Thanks for the info guys. I will try to get in touch with Bill.