Towing a Momentum 395ms

**xrated** · 09-11-2023, 05:47 PM

Originally Posted by Harrycomes

All this talk about engine braking. None of you ever touch the brakes going downhill? Why bother even having brakes on your trailer? Between dropping to a lower gear, and my excellent trailer brakes, my gas truck stops the trailer fine.

I could be wrong here, but it sounds like you've never experienced extended length, steep, downgrades with a heavy camping trailer....otherwise you would recognize/understand the immense benefit of having diesel engine braking. We were out west back in 2021 with our rig, a CrewCab Dually towing a Momentum triple axle trailer that scaled at about 29,500 lbs combined. Coming down some of the 6% and 7% grades with the engine brake on and the transmission in Tow Haul mode, there were very few times of actually having to touch the brake pedal. If the recommended speed for the big trucks was 50 mph on those grades, right before hitting the peak and starting down, I would adjust the cruise control down to about 46/47 mph and let the truck do the work. Sometime it would gain, at most, 5mph, but mostly stayed in the 47 to about 50 mph.....right where it needed to be. And as was stated in a previous post, zero worries about overheating the brakes or warping brake rotors.

**Harrycomes** · 09-11-2023, 05:55 PM

I know exactly how engine braking works and the benefits. However, a properly set up truck and trailer shouldn't need them to stop. Are they nice? Yes. Are they required? No.

**Overtaxed** · 09-11-2023, 07:56 PM

Originally Posted by Harrycomes

I know exactly how engine braking works and the benefits. However, a properly set up truck and trailer shouldn't need them to stop. Are they nice? Yes. Are they required? No.

In normal operations, no, they aren't required and brakes work just fine. However, if I'm coming off a huge grade and some idiot pulls out in front of me, I'm going to be REAL happy that my brakes are at full power and not glowing red and deep into fading.

In an emergency situation, it's all about buffer. We all have to decide our personal risk profile, some feel they have plenty of buffer with a truck of one size, others want a lot more buffer and have a bigger truck and some want the max buffer and tow their RV with a semi. Is it required? Absolutely not. Is a dually better than a SRW, and a class 8 tractor better than a dually in an emergency? They sure are.

Also, you have to think about your exposure. If my friend wanted me to move his SpaceCraft (35K lbs) 5 miles down a country road, I'd do it with my 450 and not blink an eye. I'd go very slow, and I'd make sure we had the route planned out, but, absolutely, I'd do it and feel fine about it despite being WAAAYY over on payload and towing capacity. If he wanted me to tow that same RV across the state, or up a mountain pass in the Rockies, I'd tell him to find someone else, the exposure is much higher and the risks increase substantially.

To the original post, if I was towing a 395 a few 100 miles a year on roads I know well and in controlled conditions (not snowing/raining/low visibility/etc), I'd be fine doing it with any modern heavy duty pickup (250/2500 or better). If I was towing my 395 cross country and putting 1000's of miles a year on it in very varied conditions, not a chance I'd do that in a SRW truck.

**BobKilmer** · 09-11-2023, 08:27 PM

Originally Posted by Overtaxed

Engine braking downhill is the thing that got me to go up to a dually; going uphill is almost all engine, and any modern pickup has plenty. Going downhill with the engine brake, all the braking force is on those 2 rear wheels, the RV isn't helping and the front tires aren't helping. That always felt "loose" to me (towing a 351M with a 2019 F250), like the RV was trying to push the truck around (which, of course, it is). Going up to a dually improved every aspect of the towing experience, but the downhill/hard on engine brake was the area I'd say was close to the top for improvement (the other, unsurprisingly, is stability in a crosswind, the dually feels quite a bit more planted when the wind is against the side of the RV).

The "pushing" behavior you describe is the behavior of a truck loaded beyond its towing limits, not a SRW versus DRW behavior. The SAE J2807 towing test specifically tests for this behavior with their Front Axle Load Restoration (FALR) tests which drive the truck GVWR. I would expect that behavior with the combination of an F-250 and a 351M.

I have an F-350 SRW that is not overloaded with my 381M and there is no pushing behavior during downhill engine braking or any other conditions.

**BobKilmer** · 09-11-2023, 08:50 PM

I noticed that most people who state their DRW truck is better than their previous SRW truck are comparing an F-250 SRW to an F-350/450 DRW. With that, I have a question for everyone who has posted here that their DRW truck is better than their previous SRW truck.

Is there anyone who can say they had an actual 1 ton SRW truck that they used within the towing limits and that switching to a DRW truck was better?

Modified F-250s or trucks prior to 2015 that are not in compliance with SAE J2807 are not in my mind valid 1 ton trucks. And saying you were within your tow limits doesn't count unless you actually weighed the truck/trailer combination to verify you weren't pushing the SRW truck beyond its limit.

I ask this question because I have a 1 ton SRW truck that is towing a 381M with excellent performance. I know it is being used within its limits via multiple CAT scale measurements. I have no issues with pushing on downhills, winds, or any other towing conditions. The truck and trailer combination are receiving a lot of use. I am coming up on 40,000 towing miles in 4 years under all conditions. In the next two weeks I will have completed visits to all 48 CONUS states. I have been across the continental divide four times and traversed downhills up to 11% with no issues. I make sure I stay within my towing limits and have never seen an issue where I felt the truck was a limiting factor. That is the intent of the SAE J2807 limits and my experience is consistent with that intent.

**xrated** · 09-12-2023, 08:03 AM

Originally Posted by Harrycomes

I know exactly how engine braking works and the benefits. However, a properly set up truck and trailer shouldn't need them to stop. Are they nice? Yes. Are they required? No.

Your right, you don't need them. You have options....like burning up the brake pads and warping calipers on long downhills that you quite commonly find out west

And your implication is that I don't have a properly setup rig, and I'll certainly beg to differ with you there.

2016 F350 Dually 6.7L diesel with the 3:73 rear end. GVWR 14,000lbs, Payload 5270 lbs, Gross combined weight rating 31,900 lbs, RAWR 9900 lbs, FAWR 61xx lbs.

2018 Momentum 394M...triple axle, GVWR 20,000 lbs, three 7000 lb axles, six Sailun 235/85R16 tires....4400 lb capacity per tire, B&W Companion 25K hitch

Every single weight/capacity rating for both the truck and trailer is under the listed manufacturer's ratings.

And again, as has been mentioned several times in this conversation....we aren't talking about "stopping" here, we are talking about maintaining a safe, predetermined speed while descending down long, steep, mountain grades to be able to protect the brake pads/rotors from constant usage....while descending

So I ask you again....have YOU ever experienced (you already said you know how engine braking works and the benefits) that exact situation.....towing a heavy 5th wheel camper and descending long and steep mountain grades?

**mwdilday** · 09-12-2023, 08:13 AM

Originally Posted by Harrycomes

All this talk about engine braking. None of you ever touch the brakes going downhill? Why bother even having brakes on your trailer? Between dropping to a lower gear, and my excellent trailer brakes, my gas truck stops the trailer fine.

Engine braking on my Ford 6.7 Powerstroke will hold the speed going down the steepest hills I have travelled on in excess of 8% for a mile or two or more. Never touch the brakes going down hill. Asking why even have brakes on the trailer? Well I don't know what to say about that.

**Harrycomes** · 09-12-2023, 09:34 AM

Originally Posted by xrated

Your right, you don't need them. You have options....like burning up the brake pads and warping calipers on long downhills that you quite commonly find out west

And your implication is that I don't have a properly setup rig, and I'll certainly beg to differ with you there.

2016 F350 Dually 6.7L diesel with the 3:73 rear end. GVWR 14,000lbs, Payload 5270 lbs, Gross combined weight rating 31,900 lbs, RAWR 9900 lbs, FAWR 61xx lbs.

2018 Momentum 394M...triple axle, GVWR 20,000 lbs, three 7000 lb axles, six Sailun 235/85R16 tires....4400 lb capacity per tire, B&W Companion 25K hitch

Every single weight/capacity rating for both the truck and trailer is under the listed manufacturer's ratings.

And again, as has been mentioned several times in this conversation....we aren't talking about "stopping" here, we are talking about maintaining a safe, predetermined speed while descending down long, steep, mountain grades to be able to protect the brake pads/rotors from constant usage....while descending

So I ask you again....have YOU ever experienced (you already said you know how engine braking works and the benefits) that exact situation.....towing a heavy 5th wheel camper and descending long and steep mountain grades?

Good for you. I can down shift my truck and maintain speed without riding my brakes, too.

There's a lot of chest puffing in this thread..

**xrated** · 09-12-2023, 10:03 AM

Originally Posted by Harrycomes

Good for you. I can down shift my truck and maintain speed without riding my brakes, too.

There's a lot of chest puffing in this thread..

No chest puffing at all, just an explanation of how the engine braking, combined with the Tow Haul mode works....which includes automatically downshifting the transmission to help with process of maintaining the desired speed for the descent. Also an explanation of what my tow vehicle and trailer is, with an explanation of weights/capacities that show that it is within all specs and "not out of spec" as you have suggested/stated in a previous post

And you never did answer my question about YOUR experience with heavy towing down long and steep grades like the ones commonly found out west. Maybe you have no experience with that, and that's OK, but engine braking, Tow haul mode, and Cruise Control all working together on those types of roads/highways, serve a very useful purpose, whether you've experienced it or not.

**Hoopy Frood** · 09-12-2023, 10:05 AM

Originally Posted by Harrycomes

Good for you. I can down shift my truck and maintain speed without riding my brakes, too.

There's a lot of chest puffing in this thread..

Not really, just real world experience. And, honestly, a gas engine isn't going to be able to generate enough engine braking on long steep downhills to keep the speed down if you have a big heavy trailer behind you.

I have no idea what you're towing, but the people who are towing heavy, i.e. over 15,000 lbs., are not chest puffing, just being realistic.