I have a question about the 2nd gear . It is like a hill holder or line lock with my 2nd gear. You really need to give it some throttle (gas) to get it going. In 2nd gear only my truck will NOT roll back on a hill . I like it if this is normal . I have been waiting for a post about this from day 1.

 

What you are experiencing is normal. When shifted into second, your torque converter is locked. That's why it won't roll backwards on a hill. It will also dog like crazy. If you are driving with the shifter on '2' , and then shift into 'D' without moving your foot from the throttle, the RPMs and power will surge when the torque converter unlocks.

In 'D' (normal driving) your torque converter only locks up in 4th gear.

It is not like 'normal' setups; i.e. if you shift into 2nd on most auto trans vehicles, you will disable anything over 2nd gear. If you are stopped, and hit the gas, the tranny will start in first, then shift to second, and that's all it will do.

On our trucks, shifting to '2' will keep the tranny only in second gear (and lock the TC as well).

Why would Ford (or anyone for that matter) want the TC locked in 2nd? This serves two main purposes, both of which are the main reasons someone woud shift into second.

First, you get better engine braking when descending a grade with a heavy load. Without locking it, a lot of the retarding force is lost through the fluid coupling.

second, it is Ideal for taking off from a stop in slippery conditions. If you've ever had a manual trannied car/truck, you probably already know that when on snow or ice, starting in 2nd gear would allow you to accellerate without breaking the tires loose. That was always a downside of Auto transmissions in the standard 1 + 2 2nd gear I mentioned earlier. So, the TC locking prevents you from rolling backwards and needing to raise rpms to take off, and also lowers your rpms more than 2nd gear alone would. So now in winter driving conditions, you get the bennefits of a manual, but also some added help.

Anyway, that's why it is the way it is. Hopefully not too confusing, I've got a couple of brews in me.

I for one very much like the way our second gear is designed

 

Very informative inbred, thats stuff I didnt know either,
you are a plethora of information!
thanks!

 

well, I think that's mostly correct at least. going from old memories; it's been brought up a couple of times here before...

Hopefully someone can confirm my accuracy.

 

Question....how can the torque convertor be "locked" when you shift to 2nd and still sit at a stop without the engine stalling??

If the convertor is locked there is no slippage between the engine and the transmission, so the engine will stall at a stop. Just like a stick shift would.

I think you'll find, not sure though, that when in 2nd there is a band that comes on in 2nd manual position to give engine braking. AOD's and AODE's did this. The band wasn't used in the normal operation of the transmission while driving in "D".

 

Excellent post inbred....I've learned something else new from this site. This info would have been helpful last night when I was out driving on the nasty roads.

Apparently the highway crews here don't work on the weekends judging by the condition of the roads last night.

 

Thanks good info. I new it was a good thing.

 

Yeah, somebody on here had said the TC lock in second thing sometime back, although I can't find it now. Never did make too much sense to me. Something definately happens to reduce the tc slippage though...

 

-The converter is not locked with the truck in manual 2nd.

-The reason for the engine braking is there is a band that is engaged to prevent the intermediate sun from spinning.

-The converter does lock up in other gears in the 'D' range.

In fact, the only time the converter reaches lockup in 2nd gear is when the shifter is in the 'D' range and is accellerating.

 

correct

also , there is never a scenario where the brake pedal is pressed and the converter is locked.

 

I just moved to Central PA and I've got a 14% grade that I have to negotiate Every day now. I definitely find myself using the console shifter and 2nd gear, both while descending the hill as well as starting up it. Starting out in 2nd gear Does limit the wheel spin when it's wet out, even with the posi rear end.... Definitely a good function!

 

kidtriton is correct on all items. If it were me I would listen to him.

 

As would I. Thanks for the help

 

<clip> "The reason for the engine braking is there is a band that is engaged to prevent the intermediate sun from spinning."

Whats an intermediate sun?

 

It is part of a planetary gear set.

http://auto.howstuffworks.com/automa...nsmission2.htm