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Using the Trans for Engine Braking?

sbi

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I am not an expert either but I highly doubt that the transmission on these trucks can't handle "engine breaking". I use it if needed, always have (in other vehicles) and always will. If this causes the transmission to fail....well, it will be a hint that we should buy something else, but I don't think it will.
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FirstFord

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When you press the minus key, it removes gears the truck can you use. It's not manual mode, it's just removing gears it can use. I have a raptor wheel so it's easier than using the shifter.
Damn! I never knew that! Just learned something (and that's always a good thing). I've always pressed the "M" button, then selected the gear I wanted.
 
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FirstFord

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I am not an expert either but I highly doubt that the transmission on these trucks can't handle "engine breaking". I use it if needed, always have (in other vehicles) and always will. If this causes the transmission to fail....well, it will be a hint that we should buy something else, but I don't think it will.
I hear ya! And me too - as I said from the jump, it was a regular practice for me. Then I went and read that freakin' article, and it gave me pause... :oops:
 

HammaMan

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Manual mode is interesting. Right around 36 mph is where it will take 8th gear and you can get a feel of the power band (3.73 ratio). I was doing heat soak testing of the factory intercooler and found that no matter what I did it was holding ambient + 20 degrees even at 20psi at the IAT.
 

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Manual mode is interesting. Right around 36 mph is where it will take 8th gear and you can get a feel of the power band (3.73 ratio). I was doing heat soak testing of the factory intercooler and found that no matter what I did it was holding ambient + 20 degrees even at 20psi at the IAT.
Our Powerboosts have very high IAT2 and IAT temps because of the ICE shutting off and no fresh air traveling through the intake tract. Once the hardware, namely the block, gets good and heated up, it heat soaks the intake and cooks the stale air.

Admittedly the IAT2 temps will drop ~10F or more within seconds of the ICE lighting up, but from what the PIDs show, the intake temps are already 30 or more degrees above ambient.

It'd be cool (pun?) if there was a way for fresh air to be circulating through the intake during EV mode.
 

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HammaMan

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Our Powerboosts have very high IAT2 and IAT temps because of the ICE shutting off and no fresh air traveling through the intake tract. Once the hardware, namely the block, gets good and heated up, it heat soaks the intake and cooks the stale air.

Admittedly the IAT2 temps will drop ~10F or more within seconds of the ICE lighting up, but from what the PIDs show, the intake temps are already 30 or more degrees above ambient.
Yeah, even with ICE on and low-load the temps are up there. I was seeing between 30-40f + delta a.t. That was the point of my tests to be rolling ~35 and get into 8th gear and go wide open up to 80mph and as soon as WOT condition was met, the IAT2 was holding at +20 ambient even at 20psi. I was beating on the truck for nearly an hour and couldn't get the stock intercooler to degrade. This is with a 500whp tune.
 

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Just cruised the Owners Manual;

From the Tow Haul drive mode it says
" For improved transmission operation when towing a trailer or a heavy load. This mode moves upshifts to higher engine speeds to reduce the frequency of transmission shifting. This mode also provides engine braking in all forward gears, which slows your vehicle and assists you in controlling your vehicle when descending a slope. The amount of downshift braking provided varies based on the amount you press the brake pedal. "

It proved very useful in upstate NY earlier this year. I am sure I'll give it a work out next July when I'll be towing in Colorado.
 

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Compare the costs of rebuilding the transmission against the cost of new brake pads and the answer is obvious. If you want effective braking then you need a diesel truck with an exhaust brake.

I get more than 100,000 miles on my truck and car brake pads and 90% of the wear is usually at the front wheel so only the front pads would need to be replaced. Shorter life would indicate a sticking brake piston of bad factory rotors.
 

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Actually with modern day ABS logic being used for traction control and Antisway, an F150 can experience accelerated rear pad wear beyond what one might expect.

Not everyone will be affected, but it's surprised more than a few to find their rear pads worn quicker than the fronts.
 

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i use downshifting a good bit, to save heat on the brakes if in hilly roads.
i also lock out upper gear a good bit
i use sport with 9 and 10 locked out A WHOLE lot on my drive to the big city to see my doctor, its a nice winding road with hills and dips, makes for a great spirited drive
if i have to be on a road that is 60 , i will lock out 9 and 10 so its not doing the downshift all day

i will admit downshifting or using tow haul is not as aggressive in downshifts as the super duty
my 06 350 could chirp the rear tires when empty if you were aggressive in driving

i question the transmission tech statements as the book gives us an OK to do it.
and like snakebitten stated...if it was wrong...where are the warranty claims???
 

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Great discussion. I don't use it locally or daily.
Still learning, but been using it more and more often on overland trips on long steep road descents to prevent overheating front brakes. ie 2H M3 ie High Sierras, Death Valley, San Bernadino's
I hate hot spots, warped rotors, chatter under threshold braking etc. (Like poerboatr said spirited time)
Also between trails at 15psi trying to keep it under 45mph.

Off road is whole other realm. 4L M1 are essential for enjoyable hill descents. Rocks, Sand, bench roads, etc. Can be difference between fun and a broken, stuck truck or dead people.
In auto it can runaway, in 4L M1 have to be careful getting it stopped not run into rig in front of you. LOL.
Been using 4H M11, M2 more too it's nice on mild dirt, sandy or dune descents etc.
 
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EricR

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I live in a pretty hilly area, and a few of them are fairly steep. It was a very common practice for me to drop it down into low gear before descending these steeper hills to help save my brakes by utilizing engine braking.

Then I read this article - something like "The Quickest Way to Ruin Your Transmission" - written by some transmission expert, who made the claim that engine braking is very old-school way of thinking, and "modern" transmissions shouldn't be put through that. The author insinuated that "modern" transmissions aren't as rugged and beefy as the transmissions of yesteryear and they aren't built to handle that kind strain. He further implied that using a "modern" transmission for engine braking is abusing the transmission. So, after reading that, I have temporarily halted this practice.

I will fully acknowledge that he may be correct, yet I'm a little skeptical of that point of view. Anyone out there in the transmission field who has a comment on this? I'd really be interested in hearing your thoughts.
Are you using cruse control?

Our '21 Lariat PB does a remarkable job at retaining the set MPH with little driver intervention out here in the mountains of Idaho.

The same is true when towing our 5,000 Lb (down the road weight) using the Tow/Haul mode.

When going down Horseshoe Bend Hill (5,000 FT to 2,500 FT in short order) I'll put it in Tow/Haul even if we're not towing - and it handles the decent wonderfully.

We drive Horseshoe Bend many times each year and I am repeatedly amazed at how well the cruse control selects the various lower gears to limit our downhill momentum at the set speed! Unless the recommended speed changes dramatically we hardly touch the brakes at all. Just WOW!

Without cruse control it's brake, wait, brake, wait, wait, brake, brake, wait, brake -or- manually downshift, downshift, upshift, downshift, upshift, downshift, downshift, upshift - to try and keep up with the variations in terrain.


Disclaimer: I don't know if it matters, but our truck has Adaptive Cruise Control.



PS - That flatlander Snakebitten has nothing on me with this topic! :LOL:
 
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tony72cutlass's'

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By the way, there are many thousands of these trucks traveling downhill in the Rockies.
My 5.0 was absolutely screaming going down a cliff edge road in maine over the summer. Handled it perfect.

Sounded unreal too honestly like an angry swarm of bees
 

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I live in a pretty hilly area, and a few of them are fairly steep. It was a very common practice for me to drop it down into low gear before descending these steeper hills to help save my brakes by utilizing engine braking.

Then I read this article - something like "The Quickest Way to Ruin Your Transmission" - written by some transmission expert, who made the claim that engine braking is very old-school way of thinking, and "modern" transmissions shouldn't be put through that. The author insinuated that "modern" transmissions aren't as rugged and beefy as the transmissions of yesteryear and they aren't built to handle that kind strain. He further implied that using a "modern" transmission for engine braking is abusing the transmission. So, after reading that, I have temporarily halted this practice.

I will fully acknowledgethat he may be correct, yet I'm a little skeptical of that point of view. Anyone out there in the transmission field who has a comment on this? I'd really be interested in hearing your thoughts.
No reason to drop.....just take your foot off the gas. No reason to brake either.

Up and down hills all the time. Just coast. The tranny downshifts on its own
 

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I used Engine Braking a lot during my last camping trip from FL to NC. Locked out get 8-10 and downshifted to lower gears on the long downhill runs so I didn't have use much brakes. Tow/Haul mode all the time and it worked great while I was towing my 4400# TT in the mountains of N. Ga and NC. Also, used some engine braking while the TT wasn't connected.

Ford F-150 Using the Trans for Engine Braking? IMG_4901.JPG
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