Must be a 2009+ thing. My '08 will all but come to a stop using the engine alone. Just have to keep the engine speed down.

With your injectors firing for idle your engine is an air pump...there is braking there, but yes, the more restriction you can put on the air pump, the better the braking. Since you still have compression it still takes work to turn the engine over.

 

TexasRebel,
I'm surprised there is that much difference. Your 4.10 axle ratio should give a slightly better result than my 3.73, but I feel that I'd really have to abuse my vehicle downshifting to slow just by using the engine. I think the only way the vehicle might come to a stop is by completely shutting off the engine!

The RPMs take a full 2 seconds to drop back on a shift. No matter what I do, I can't get a decent shift in any less than 2 seconds. When cold, there is no way I can do a 2 second shift from 1-2 or 2-3.

1-2 will result in slight clash and 2-3 can grind. I'm sure cold for me is WAY colder than you ever see in Texas.

Cold requires 3 or 4 seconds for the 1-2 shift and 4 or 5 seconds for the 2-3 shift. Warm, I can do a 2 second shift on all shifts except for 2-3 which still needs 3 seconds. This is slower than the 40s and 50s cars I had with column shifts.

For me, this is the first stick vehicle that is a PITA in traffic. When I back off, the revs take 2 seconds to drop, then I get very feeble engine braking. It gets a bit better the longer I wait, but still isn't enough to be much good. Keep in mind, this is on an unloaded vehicle without a trailer.

Normally with proper engine braking, I'd rarely use my brakes unless I had to stop completely. With this Ford, even trying to maintain a large gap in traffic doesn't work.

I guess all modern vehicles are failures when it comes to driveability. My revs actually flare slightly on the 3-4 and 4-OD shifts before dropping back. How's that for retarded FI programming?

 

Talk to 5 star, they can fix the PCM tuning that is causing that.

 

I'm reluctant to spend the money considering it could impact a warranty claim. I will check into it at some point. It would be nice if someone with a similar vehicle had all these problems cured by using a tuner.

I would get more interested in a tuner if it actually allowed me to modify the throttle closing rate. A "canned" setup might not be ideal.

The throttle closing/engine braking characteristic and the very bad cold weather bog from 1200-1800 RPM are the significant problems.

It would be great if a faster RPM drop would also allow the ZF to shift quicker, but I doubt that a tuner will make any difference when it comes to the mechanical function of the gearbox.

 

They don't do canned tunes, its custom tunes.

I have not got one for the V10 yet but I have one on my old cop car and love it.

 

I also tend to get a bump from 1-2 and a clash from 2-3... and that's when it is 70 degrees outside.

Cold shifting (40F or less) is very difficult until the oil warms up a bit. The "fix" for that is to trade the MTF out for ATF since it is thinner. I refuse to.

Neil, does your transmission make any noise when rolling to a stop?

as far as engine braking, I tend to use my clutch quite a bit to keep my engine speed down. I'll keep an eye on the tach after a downshift to make sure it doesn't pass 4, and clutch if it tries.

 

My truck behaves in a similar manner that you are describing with cold shifts and engine revs. When I take my foot of the accelerator, the engine kinda hangs on the rpms before dropping.

On my '79 F350 with the 4sp, as soon as you let up off the accelerator the engine would return to idle rpms almost instantly.

I don't quite experience the lack of engine braking that you are describing. I tired doing what you described in your earlier post about coasting, then disengage the clutch, wait 1-2 seconds they let it out. It seems to engine brake ok. I only did this with 3rd gear though.

 

Both of what you described has happened to me also.

 

Neil E ,There must surely be something wrong with your truck if it takes 2 to 3 seconds go from one gear to the next. Granted it will take longer to shift when cold but not 2 or 3 seconds when warmed up. I have no gear clash when shifting. As far as RPM flare when shifting, as I told you some time ago, let off the throttle before depressing the clutch.Works well for me.And I say again that this transmission is the best one available in a domestic pickup truck.

 

GVS,
I understand what you are saying, but I just can't do it any other way.

Every vehicle that I've had for years now, returned to idle quickly and you wouldn't back off the throttle BEFORE a shift. It was always back off and press the clutch pedal simultaneously.

If I try for a faster shift (less than 2 seconds) I get the 1-2 clash or 2-3 grind. Now maybe when I say less than 2 seconds, I really should say 1.5 seconds, as I haven't used a stopwatch. I just do a one-thousand/two-thousand count while shifting. This is probably bugging me so much now because we are in the dead of winter and it rarely gets above freezing.

I am good at matching revs since the tach needle barely twitches on clutch engagement. I know the clutch should only slip the tiniest bit while getting underway. The 5.4 is soft right off idle, so I usually have to rev it a little above idle when starting out.

The whole idea is to engage the clutch at minimum revs and let the engine do the work.

Whatever the exact shift time is, it just feels darn slow. I was spoiled having a New Venture NV4500 for the past 15 years. Longer throws but faster shifting with more positive detents. The NV4500 would clash slightly on the 2-3 shift when dead cold.

I can live with the slow shifting; it's the weak (and DELAYED) engine braking that's the most frustrating. I'm not saying it has absolutely no engine braking, it's just MUCH weaker than any vehicle I've ever driven.

The gearbox doesn't have any unusual sounds. The initial travel getting out of the 1-2 gate (going over to the R-L gate) is very notchy and takes more of a slap than I prefer.

 

hey look...

a conversation that the auto guys can't chime in on

 

With my 7.3 I have to press the gas to maintain speed going downhill. I can be doing 60 mph in 5th gear and let off the gas and it will slow down to 40 mph before I get to the bottom. My 5.4 picks up a little speed going down hill. It has about half the compression though, so that's expected. Both are manuals with 4.10 gears.

Give them time

 

I am a guy with an auto, but I really wish I had the ZF6 speed.

Where does that leave me in this argument?

 

My auto never grinds...and shifts in a fraction of a second.

My auto has a button for that!

The difference has nothing to do with compression. Diesel engines actually spin easier than a comparable gas engine due to the fact that they are unthrottled. My 15.2L Cat diesel in my work truck is completely USELESS for engine braking until I turn the jakes on. This is the big reason why diesels need engine brakes!

The difference for you is fuel injection programming. On my 6.4 as soon as I let off the pedal fuel consumption goes down to 0.0 GPH, meaning the injectors aren't even firing. On my '07 F150 the engine was still getting fuel.

The gas will actually be much more effective than the PSD if you can get a program to close the IAC valve and throttle plate as well as completely shut off fuel delivery. Stock programming doesn't allow for that though.