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Discussion Starter #1 (Edited)
I know nothing about exhaust brakes, or even how well the stock F350 does holding back towing loads on steep down grades. So I plan to eventually buy a 5th wheel. The heaviest trailer (wet load) I’ll be able to tow will be around 11,500 lbs to stay within the manufacturers 20K GCVW. The steepest pass I have ever drove (not towing) is Wolf Creek Pass in SW Colorado to and from Pagosa Springs across the Rockies San Juan National Forest to elk hunt- so I’ll use that grade as an example.

I realize the 5th wheel has electric brakes. How do the combined braking systems (truck/trailer along with A/T down shifting work on a downhill grade like this towing a 11K trailer. Is it anything to be concerned with using the superduty 7.3L trucks and if so is an add on exhaust brake needed. I live in Illinois so mountain driving will be limited to vacations and hunting trips.

I’m sorry for all the novice questions, but would like to plan ahead while I’m “building” this truck for dependable towing for retirement in the not to far distant future
 

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Discussion Starter #2
I just found an old post on here (9/4/2008) in which OP stated he was told Ford did not reccomend exhaust brakes on 7.3
Smokey Wren confirmed Fords stance but said he knew of no damage to the engines caused by exhaust brake. Smokey was just getting ready (2008) to try one out and report back but I can’t find any follow up on the old posts. ?
 

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I have over 200000 miles on two 7.3 with exhaust brakes. Mine are (were) a 96 and currently a 99 both with manual transmissions. The 99 has the original brakes on it, with loads over the 20000# GVW and lots of mountain driving. I’m presently replacing the uppipes, which could be due to exhaust brake use or a lacking design. On a steep grade, it really helps with any load. With an auto, you’ll need tuning or something like a Banks TransCommand to hold lockup in the transmission.
 

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Discussion Starter #4 (Edited)
I found an older post by Mark Kovalsky (2008) that may have answered my question, partially, on the capability of the stock truck’s braking ability using the engine/AT along with the truck/trailer brakes.
I believe Mark said by disengaging the OD button—turning the light off/OD off, the coast clutch (4R100) engages in gears 1, 2, & 3 and the transmission now drives the engine, allowing the engine to idle, and giving a breaking “effect” instead of the engine driving the transmission and No need for the t/c to be locked.

As long as I didn’t misunderstand-
So with that said, and with a Diesel engine having much higher compression than a gasser I would think the braking effect would be significant, but I’m still not sure how much assistance this would give to the braking effect on an 11K trailer on a downhill grade (8%) as I haven’t towed yet.

Though I’m sure for those living in a mountainous region, an exhaust brake may not be a bad idea.
 

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With any 18 wheeler s you go down hill in the same gear you go uphill. If you over heat your brakes you are going downhill to fast. Your diesel engine should be able to hold back your speed with just the engine.
 

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I don't have an engine break and I have pulled a 22,000 lbs trailer through the Smokies a few times a year with my 2002 F-250 7.3. just make sure breaks are good on both truck and trailer and should have no issues.
 

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I found an older post by Mark Kovalsky (2008) that may have answered my question, partially, on the capability of the stock truck’s braking ability using the engine/AT along with the truck/trailer brakes.
I believe Mark said by disengaging the OD button—turning the light off/OD off, the coast clutch (4R100) engages in gears 1, 2, & 3 and the transmission now drives the engine, allowing the engine to idle, and giving a breaking “effect” instead of the engine driving the transmission and No need for the t/c to be locked.
Almost.

Turning on the OD OFF light (overdrive disabled) does engage the coast clutch in gears 1, 2, and 3. Whether or not the torque converter is locked the transmission will drive the engine in a coasting condition.

The problem is that engine braking (not breaking - breaking is when something fails and has to be repaired) is minimal on a diesel engine. Yes, the compression is higher, so it takes more force to compress the air in the cylinder, but once the piston passes top dead center you get almost all of that force back as the air is allowed to expand as the piston moves down the bore. Big diesels have true engine brakes where the valves are opened at top dead center to vent the compressed air. This prevents the gain I explained above.

The engine brakes available for the 7.3L is more properly called an exhaust brake. It's just a gate that closes the exhaust when braking is required. The engine has to work much harder to pump the exhaust past this gate. That provides the retarding force.

In a gas engine, the throttle plate is closed when coasting. The engine has to work hard to suck air past the throttle plate. This naturally provides a retarding force that the diesel engine doesn't have..

You will have some retarding force without an exhaust brake. You'll have a lot more with one.

The 7.3L has a gate already in the exhaust. It's a warm up valve. Many people have added a switch to manually turn this gate on which works just like an exhaust brake. I did this years ago on a 7.3L and it made a huge difference.
 

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Discussion Starter #8
[QUOTE=Mark Kovalsky; (not breaking - breaking is when something fails and has to be repaired)

My Bad ?


Thanks Mark- I’ll look into that EBPV (warm up valve) and see if I can find instructions for wiring that up.
 

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Discussion Starter #9
And I apologize to the group/forum, I didn’t realize until after the fact that there was a “Towing” forum— I probably should have started the thread there.
 

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I put a DP tuner with Exhaust Brake tune on my 2001. It works great, and an easy"ish" install.
 

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https://www.thedieselstop.com/forums/f14/ebpv-652504/
Link for how to turn your EBPV into an exhaust brake.

https://www.dieselperformance.com/shop/product/1027144-exhaust-brake-1999-2003-ford-7-3l-powerstroke-air-remote-4in-c-w-compressor-16186
Link for buying an exhaust brake from BD Diesel Performance.

I pull an 11,500 lb trailer without an exhaust brake up and down some of the steepest grades in California with my F350 DRW, and it seems to handle fine. Not that I'm saying you don't need it. I think that you should go with whichever option you feel most comfortable with.
 

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Discussion Starter #12
[QUOTE=DonWarkentin;

I pull an 11,500 lb trailer without an exhaust brake up and down some of the steepest grades in California with my F350 DRW, and it seems to handle fine. Not that I'm saying you don't need it. I think that you should go with whichever option you feel most comfortable with.

Thanks Don, that information is helpful. I’m probably overthinking the issue as I have never towed anything but fishing boats over the years, not even large enough to require surge or electric brakes.
 

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I've been running the BanksBrake on mine for several months. Having looked at a few different units, I liked the design of the Banks best, the way it bolted directly to the turbine housing. Since my engine came with/already had the Banks "PowerElbow" on it (mated-up to a 4" down pipe), the BankBrake setup went right on, in its place.

I didn't like the electronics it came with (just didn't work well with my 6-spd) so I built my own electronics to interface with the clutch pedal switch, IVS, cruise control and GearVendors U/O. Also integrated a "speed relay" which reads the tach signal from the PCM and kills the brake at/below 1000 rpm.

Makes a good bit of difference when descending grades here in the mountains of So. Cal. Only very, very light braking needed to control the truck and my 10k trailer when winding down the grades....

Once you get one, you'll wonder how you ever got along without it!


Love it!


~Al
 
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