Ford F53 Question

[Keily]

I have a new motorhome , 2014 Adventurer 37F with the F53 362-hp 6.8l V10 Triton engine, TorqShift 5-speed automatic overdrive transmission with tow/haul. Mileage is about 6000 miles.

This is my second motorhome with the same type of engine, it was a 1999 F53 with the Ford V10. My question is regarding the tow/haul feature. In the past I always used the tow/haul when going down steep hills as an engine brake, when activated in the older engine the engine would rev up a bit to maybe 3000 rpm(depending on how steep the grade was) but the overall speed of the mh would slow down. I have noticed on the new mh, when I activate the tow/haul when going down a steep grade, the engine rev's increase quite a bit more and there a lot more of a roar coming from the engine. As the vehicle speeds up the higher the tach goes and the louder the roar, so much so I usually de-activate the tow/haul button, and use the brakes to try to slow down. Does anyone know is this normal for this new engine, I am afraid I might be doing some harm to the transmission or the engine if I leave the tow/haul activated.

Does anyone else have the same thing happening?, maybe this is normal and I got nothing to worry about.

Thank you in advance for your advice.

[Keily]

There is no red line on my 2014 tach as well. I was under the mh yesterday looking around and one thing I noticed that wasn't on the 1999 is that on the 2 front brake rotors Ford has installed some air ducts that scoop the air from the grill area onto the rotors. Nice to see that for cooling.

I also have travelled a lot of times on I40 and I77 lots of steep hills and never had a problem, just let the engine do most of the braking on the down side, and after 15 years and 178,000 Kms, the unit still had the original pads, and rotors, also I must add that every year before staring out for the new season the motor home was always into the local Ford truck center and 2 things I always wanted checked were the brakes and wheel bearings. I always needed that peace of mind when travelling.

[cochise49]

I don't think there is a "red line" on the tach in my 2014.:B

[Crazy_Ray]

What about down shifting?? I do it with my V10. Am I doing wrong?

[Dale_Traveling]

At some point on a long steep grade you're going to have to give it some hard breaking to get the speed back down to a comfortable level. Hard braking at 4000 RPM to get the engine under 3000 RPM are safe numbers. It will build up a some heat but much less than riding the brakes for a long time. The disks on an F53 are pretty big and will bleed off the heat quickly if you give them time to do so. Riding the brakes won't.

Don't worry about the high engine RPM the ECU will protect the engine to the point I think of even up shifting to a higher gear but I've never read any postings of that occurring. My engine cover was sound and heat insulated by the prior owner which helps a bunch to hold down the engine noise.

My coach is a bit lighter at 15,000 pounds but I've found the tow/haul will hold speed pretty well even with 3K Lbs. of Honda Accord pushing on the back end but I haven't been west of the Mississippi River as yet. Came down I40 in western North Carolina two summers ago. Long steep grade east of Ashland with a mandatory stop for all trucks prior to the decent. Used the brakes at the top to get my speed down to 50MPH which caused the transmission to down shift and the power train held me at no faster than 55 all the way down. RPM was up around 4K but OK for the high revving V10. At the bottom hit the cruise resume button and went on my way never touching the brake or accelerator. Had the toad brake indicator flicker a few times on the decent.

[Rodz]

hanko wrote:

Rodz wrote:
The V10 is firing 25% more cyl. per revolution than a V8 so that's part of the high rpm sound.

achoo bs

A V10 fires 5 cylinders per crankshaft revolution. A V8 fires 4 cylinders per crankshaft revolution. 25% more cylinders firing per crankshaft revolution. Like a 6cyl and a 4cyl engine running at the same time. I hope your cold gets better.

[Rodz]

The V10 is firing 25% more cyl. per revolution than a V8 so that's part of the high rpm sound.

[frankdamp]

The engine rpm limiter works on the fuel system - it isn't a physical restraint on the rotating machinery. If a heavy vehicle going down a steep grade is pushing the engine, the rpm limiter can't do anything to help, since it will already have gone to minimum fuel flow.

A lot of people used to the older V-8s, like the 460, get very concerned with the much higher rev range of the V-10. I've been around small high-performance motorcycles with engines that have peak torque at 8000 rpm and rev to 15,000. A 4-cylinder, 500cc engine doing 15000 rpm has a special sound!

If your tach is below red-line, you're fine.

[hanko]

stvdman wrote:
The difference between the prior RV and the new RV may be the rear-end gearing also.

I would imagine the new has higher gears given it is a larger coach, 37' gasser.

you mean lower gears

[stvdman]

The difference between the prior RV and the new RV may be the rear-end gearing also.

I would imagine the new has higher gears given it is a larger coach, 37' gasser.

[afrescopXx]

Forget the noise. The V-10 will downshift and rev high on most inclines. Ours will rev as high as 5,000 rpm on occasion. While loud it is normal. Just enjoy your new MH.

[Keily]

Thank you very much for these last 3 posts, it makes me feel a whole lot better about the rpm. You are 100% on the fan clutch, I had totally forgotten about that, and I do remember that from the older mh I had. I will be leaving in a couple of weeks to go south for the winter and thanks to you guys I feel better about the trip now that I have this knowledge.

Travel save everyone.

[jerseyjim]

The computer has a rev limiter built in...so you can't over rev the motor. That "roar" you hear, is, in all probablility the fan turning on to cool things off. Nothing to worry about.
My older 2001 does not have the "tow" feature you have, but does have "overdrive on/off" which, I imagine does the same thing....but you have to do it. (push a button). "Overdrive" will kick out on long steep hills (now y'gotta step on the gas) and the dash a/c cuts out (too small a vacuum cannister)until you start the downward side of the hill or until the motor slows down, letting vacuum build up. Definately an annoyance on a hot day.
My experience with the V-10 (over 55,000 on the odometer right now) is that it is bullet-proof. Just keep changing the oil and filter on any schedule you make (3000 for fossil 7000 for syn) and it will probably go on "forever".

[WyoTraveler]

Leave it in tow/haul but when the rpm gets up to about 4500 step hard on the brakes to slow down 10 to 15 mph then release your foot on the brake. Repeat the process when it gets up high again. Let the engine do the work. You will need some assisted braking but do not ride the brakes.

[Golden_HVAC]

4,000 is perfectly fine for the new - well all the V10 engines. They have a tiny piston, that is very lightweight, and a short stroke compared to the older V8. While my 97 Ford 460" 7.5L is nearly a liter per cylinder, yours is only a little less than .7 liters per cylinder (0.68 liters to be exact).

So the V10 can rev up to 4,200 RPM's all day long, and take intermitent times at around 4,500 RPM's. I would not push it much beyond 4,200 for long times.

I would keep using the tow haul mode, and especially not turn it off. What I would do if the engine rpm gets 'to high' is leave it on, and activate the brakes until you feel the engine rpm is low enough, and still above 3,600 RPM. At 3,600 RPM the engine RPM is still giving effective braking. Below 3,000, or while the tow-haul is off, then the engine braking effect is not nearly as much, and your service brakes might tend to overheat.

It is very important to have the engine braking on a downgrade.

Many times just after climbing a hill, the engine is pretty warm, and if it is blowing air over 150F through the radiator, then that will activate the fan clutch. Many times I have noticed that the fan clutch will not activate to much, or might shut off near the top of the hill, while I am still pulling about 3,000 RPM in drive. At the top of the hill, I am back in overdrive, and engine RPM's tend to drop to about 2,400, while airflow will go way down, increasing the air temp leaving the radiator, activating the fan clutch again, making the engine sound like it is roaring. This is normal, and to be expected, though it does not happen every time. I don't know if this is part of the noise that you are hearing or not, but by the time you are 1,000 feet past the summit, you should not be hearing the fan clutch roar, the engine should be cooling off. (unless is is super hot out and you are running the dash A/C - not the case this time of year).

Good luck!

If you are still worried about it, note the engine RPM and if the temp is in the normal, warmer than normal, or a little less than normal. Warmer than normal would indicate that the clutch fan might activate, while less than normal, and the clutch fan should not be there.

If the "Roar" that you are reporting is below 3,800 RPM, I would expect it to be normal, and apply the service brakes lightly will bring down the RPM to say 3,600 and you will be fine, without overheating the service brakes to much.

Fred.