Tow haul mode?

[ib_leblanc]

Pulling 10,000 lb fifth wheel with f350, 6.4 deisel.. do you have to always use tow haul mode even on flat interstates?

[JohnBoyToo]

If we r taking a poll, I only use mine when slowing down....
Even when not towing as the engine braking and tranny downshifts save my brake pads ( which aren't under warranty)

Other than slowing I don't usually use it as it holds the gears too long IMHO :.

And since its my truck hope I can drive it like I want to 🙂

[Amdavis76]

I like tow/haul mode because downshifts sooner to respond to hills, holds the gear longer, and engine-breaking automatically occurs at higher speeds.

[JustLabs]

I don't like the way the transmission shifts in T/H,so unless I want the grade brake feature,I don't use it.

Pulling my 11,000lb trailer or my 10,000lb boat,the transmission actually runs cooler without T/H.

[avvidclif1]

Atom Ant wrote:

avvidclif1 wrote:
Here's the explanation on the 6.4 Ford operation.

"I’ll try to explain. Exhaust braking closes off (blocks) the exhaust manifold, leaving the exhaust gases in the cylinders to compress and slow down the engine. Engine braking doesn’t allow fuel to be injected into the cylinder, so a vacuum is created in the cylinders, which slows down the engine, which is connected to the transmission and slows the truck down."

Copied from The Diesel Stop".

All I know is it works. Cruise control set on 60mph. It held it at 60mph down a long 6% (marked) grade. I never touched the brake. Grossing 18,100 lbs.

Proved it to me.

PS A jake brake and an exhaust brake are different things. Look up how a jake brake works on a big truck, no flapper vales, all done by holding open valves.

The 6.4 doesn't have an exhaust brake - the 6.7 does.

What you describe is correct for the 6.4, just simple engine braking combined with the integrated brake controller and tow haul telling the torgueshift when to shift.

Not sure where the "jake brake" came into the discussion.

Jake brake was an aside.

A diesel engine has almost zero engine braking as thought of in a gas engine. Ergo the exhaust brake to create a restriction. On the 6.4 Ford did things with the turbo to create a working "engine brake".

[Atom_Ant]

I think it is disabled if you come out of tow haul. Tow haul in itself can cause complications on ice

[stickdog]

I have read where using exhaust brake on wet or snow slick roads is an invitation for disaster. If that is true, then an integrated exhaust brake with TH would prohibit use of that function under those conditions?

[Atom_Ant]

avvidclif1 wrote:
Here's the explanation on the 6.4 Ford operation.

"I’ll try to explain. Exhaust braking closes off (blocks) the exhaust manifold, leaving the exhaust gases in the cylinders to compress and slow down the engine. Engine braking doesn’t allow fuel to be injected into the cylinder, so a vacuum is created in the cylinders, which slows down the engine, which is connected to the transmission and slows the truck down."

Copied from The Diesel Stop".

All I know is it works. Cruise control set on 60mph. It held it at 60mph down a long 6% (marked) grade. I never touched the brake. Grossing 18,100 lbs.

Proved it to me.

PS A jake brake and an exhaust brake are different things. Look up how a jake brake works on a big truck, no flapper vales, all done by holding open valves.

The 6.4 doesn't have an exhaust brake - the 6.7 does.

What you describe is correct for the 6.4, just simple engine braking combined with the integrated brake controller and tow haul telling the torgueshift when to shift.

Not sure where the "jake brake" came into the discussion.

[avvidclif1]

Here's the explanation on the 6.4 Ford operation.

"I’ll try to explain. Exhaust braking closes off (blocks) the exhaust manifold, leaving the exhaust gases in the cylinders to compress and slow down the engine. Engine braking doesn’t allow fuel to be injected into the cylinder, so a vacuum is created in the cylinders, which slows down the engine, which is connected to the transmission and slows the truck down."

Copied from The Diesel Stop".

All I know is it works. Cruise control set on 60mph. It held it at 60mph down a long 6% (marked) grade. I never touched the brake. Grossing 18,100 lbs.

Proved it to me.

PS A jake brake and an exhaust brake are different things. Look up how a jake brake works on a big truck, no flapper vales, all done by holding open valves.

[Atom_Ant]

ol Bombero-JC wrote:

ib_leblanc wrote:
Pulling 10,000 lb fifth wheel with f350, 6.4 deisel.. do you have to always use tow haul mode even on flat interstates?

Looking at the first couple of replies.....
you have reply from a Dodge owner with a 2006 Dodge CTD.
His info is good - but not totally correct. No point in explaining.
Then the Ford owners chime in.

No doubt Chevy (& GMC) D-Max owners will also.

Looks like even some of the FORD owners are posting incorrect info!.:R

Suggest you visit one of the several *BRAND SPECIFIC* diesel forums, so you're getting info pertinent to YOUR brand and year etc.
Also, you will find (working) mechanics and techs furnishing info.

Example: The tow-haul mode for the aforementioned DODGE CTD operates totally different between 2005 & 2006 48RE (Dodge) transmissions.
Obviously, selection and operation of the feature differs from FORD trannys.

For *FORD* diesel forums -and info-, suggest:
The Diesel Stop (dot com)

(there are others for both diesel & gas. Google- Ford diesel forums)


~

Why would anyone go to another forum to get facts - Go to the manufacturer itself.

[ol_Bombero-JC]

ib_leblanc wrote:
Pulling 10,000 lb fifth wheel with f350, 6.4 deisel.. do you have to always use tow haul mode even on flat interstates?

Looking at the first couple of replies.....
you have reply from a Dodge owner with a 2006 Dodge CTD.
His info is good - but not totally correct. No point in explaining.
Then the Ford owners chime in.

No doubt Chevy (& GMC) D-Max owners will also.

Looks like even some of the FORD owners are posting incorrect info!.:R

Suggest you visit one of the several *BRAND SPECIFIC* diesel forums, so you're getting info pertinent to YOUR brand and year etc.
Also, you will find (working) mechanics and techs furnishing info.

Example: The tow-haul mode for the aforementioned DODGE CTD operates totally different between 2005 & 2006 48RE (Dodge) transmissions.
Obviously, selection and operation of the feature differs from FORD trannys.

For *FORD* diesel forums -and info-, suggest:
The Diesel Stop (dot com)

(there are others for both diesel & gas. Google- Ford diesel forums)


~

[AnnSnow]

Tow Haul + Cruise Control
Check your truck manual... I drive a chevy diesel. Its tow haul mode not only saves my truck engine (as others have already commented on), but also my truck and trailer brakes....

When going down steep grades: In tow haul mode I set my cruise control to an appropriate speed. Tow haul + cruise control automatically keeps me in the right gear for the grade. I don't have to ride my brakes.

When possible, I anticipate lower speeds needed on curves or hairpins... I'll start with a much lower speed so that when I get to reduced speeds on curves, etc., I still don't have to brake.

Tow haul is your friend!
Ann

[Atom_Ant]

hdave wrote:
The Ford doesn't have an exhaust brake.It is a program that is built into the TH Mode

Partially right - The 6.7 does have an exhaust brake, and it's controlled automatically through the tow haul mode.

Tow/Haul Mode with Engine Exhaust Braking Function

[GPG52_]

Good response tread, thks for the technical explanation;I knew it helped but did not know the underlying mechanical workings.
Like most I always turn it on when hooked up and just sit back and let it do it's job. GPG

[hdave]

The Ford doesn't have an exhaust brake.It is a program that is built into the TH Mode