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Just returned from my first trip into mountains with my 2016 TRAVATO (GAS /Promaster 3500). When going down steep hills in Drive (D without tow Haul on) the engine RPMs surged to 4500 RPM. Almost seemed to be engine breaking since speed stayed around 45 MPH. Riding the break seemed to ease the high RPM back to around 4000 RPM. I didn't notice down shifts but it must have. Is that normal? Asking because trans needed a rebuild at 1500 mile (yep.. that's 1-5-0-0 miles) so i'm not trusting that they did a great job on it. In all other conditions trans shifted fine.

I've been driving Fords and Hondas trucks for the last 16 years where 1.5-2.5 K RPMs are normal running. Not used to seeing higher RPMs like I see in the Promaster where it seems 2 -3000 is normal driving rpms.
 

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Completely normal. I drive in the mountains in Colorado a lot and the FCA engineers have programmed an aggressive engine braking assist in the transmission. The high RPM's are a bit alarming if your not use to it but it will not harm your engine. Smaller engines are the future for fuel efficiency and emissions and they need to rev higher and work harder than the old large engines did but they are built for it. It took me a while to get use to the engine braking but after driving it a lot in the mountains I really appreciate it now.
 

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I notice the same on my diesel. If I drive on CC on, about 45m/h set, trans downshift riding down-hill
 

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....cut....

I've been driving Fords and Hondas trucks for the last 16 years where 1.5-2.5 K RPMs are normal running. Not used to seeing higher RPMs like I see in the Promaster where it seems 2 -3000 is normal driving rpms.
My experience with different Ford motorhomes with V10 gasoline engines is that engine braking can easily push the engine beyond 4,000 RPMs depending on driving conditions.

It is a function of many things, including engine size, vehicle weight/mass, road slope/grade, initial vehicle speed, selected gear ratio, etc....

I personally don't ride the brakes because if/when they overheat and fade, it can be too dangerous to stop. I will use the brakes to slow enough to engage a lower gear that will allow engine braking to hold the desired speed.

For example, if doing 50 MPH at 5,000 RPM is too fast for road conditions, or if vehicle keeps going faster, I may use the brakes to slow to 25 MPH where a lower gear at 4,000 RPM won't allow the motorhome to keep picking up speed.

Engine braking at same RPMs can do more braking at 25 MPH than at 50 MPH and so forth, assuming same road conditions. Wind drag can obviously help some at higher speeds, but by then you may be flying off the mountain. That's why I don't count on aero drag unless it's a long straight descend with clear line of sight.

The physics of it applies to most gasoline engines/vehicles pretty much the same in my opinion.
 

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This is the one thing I dislike about my van. Since I have the automated manual in the diesel I can (and do) put it into manual mode and let it coast in 6th. Usually I have little or no use for the brakes then either. When I do use them the manual will often shift down into 5th or 4th as though it got a signal that I wanted a lower gear.... NOT! BTW my computer was flashed to the latest software two weeks ago and the downshifting on hills is more pronounced in "D" since. The brakes have sacrificial pads designed to slow the vehicle and have essentially one other moving part to wear, why would I want my expensive diesel engine turning near redline just to slow me. I can replace the pads in an hour for about $50 bucks I bet, and thats much preferable to replacing a connecting rod, and yes I have done that on engines before! Odd that this is the first vehicle that I have that does this.... oh wait, all my others are getting close to 20 years old and that's before we wern't allowed to think for ourselves. When someone hacks the software for this diesel and I can program it myself it's getting a NO HILL DOWNSHIFT added! Curmudgeon rant over.
 

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You should be able to tweak the computer with just a half turn of a Leatherman. Diesels might need less of a turn, now that I think about it.
 

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This is the one thing I dislike about my van. Since I have the automated manual in the diesel I can (and do) put it into manual mode and let it coast in 6th. Usually I have little or no use for the brakes then either. When I do use them the manual will often shift down into 5th or 4th as though it got a signal that I wanted a lower gear.... NOT! BTW my computer was flashed to the latest software two weeks ago and the downshifting on hills is more pronounced in "D" since. The brakes have sacrificial pads designed to slow the vehicle and have essentially one other moving part to wear, why would I want my expensive diesel engine turning near redline just to slow me. I can replace the pads in an hour for about $50 bucks I bet, and thats much preferable to replacing a connecting rod, and yes I have done that on engines before! Odd that this is the first vehicle that I have that does this.... oh wait, all my others are getting close to 20 years old and that's before we wern't allowed to think for ourselves. When someone hacks the software for this diesel and I can program it myself it's getting a NO HILL DOWNSHIFT added! Curmudgeon rant over.
Just a heads up, I replaced my brake pads and bled the system last week and the stock Brembo pads sell for around $230 for the front and about $200 for the rears. I was surprised that all the pads wore at exactly the same rate. My rear brake shoes in my GMC lasted much longer than the fronts. The pads are really easy to replace, a lot like my track car. I certainly wouldn't pay a mechanic to do it. I heard they want $1500! Another note is the brake system holds a lot of brake fluid! I used over 4 quarts and I'm still not sure I got all the old stuff out.
 

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Whoa! Those are cheap! I'd like to hear how they perform. I, unlike many here, have never had an issue with my brakes. They never made noise, except first thing in the morning, and have incredibly good bite. I do several track days a year with my Z and fully understand what a good brake setup can do. I'd be a little worried about cheap pads. Another tidbit I discovered when ordering my pads is the new replacement pads that "fix" the squealing some poeple were having are around $400 and require a purchase of additional shims! Now that is expensive! My race pads don't even cost that much.
 

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50k miles and my pads and rotors are hardly worn on either the front or rears. I would have no problem using these replacement ones if I needed them tho.
 

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Is cheap sure to be an issue? I have a Toyota 4 Runner (245K miles) with the larger rotors on front. That vehicle is notorious for warped rotors which I have had over and over. Last replacement set I opted for the cheapest China ones my parts guy could source since they were a supply item with such short life. They were $25 each IIRC. I have run them for 80K, no warp! Who knew? Price is related to many things and one CAN be quality. I'd try the $37 pads. Then when I coast down hill in 6th I'd feel like I was saving my engine at a cost I could afford.
 

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The world is full of people who believe a higher price is a sure sign of higher quality and a few regularly post here, in fact. If people have money to throw away that is well and good it's their right to spend it whatever what makes them feel good. Some people are always convinced that more is better and there is no point in pointing out to them the fallacy in that thinking.

Brake pads and rotors are disposable item, made to wear out. The cost to manufacture OEM pads is most likely identical or minimally more expensive than aftermarket pads and typically they do not perform any better. Paying for the dealers overpriced OEM pads only serves to increase the dealers profit margin.

I discovered, when I owned my Sprinter, the identical parts the dealer sold were often available from other sources for a fraction of the dealers prices and came with the same OEM numbers and markings as those from the dealers but often in a plain box rather than one with the manufacturers logo on it. Occasionally the MBZ star would be ground off but even that was unusual.

The bottom line - cost does not always equal higher quality only more aggressive marketing forces.
 

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Cheap rotors? On the truck I traded off on the Promaster I had a national chain parts store bargain Disc brake rotor high-hat separate from its rotor which left me 40 miles from home with near zero brakes, in rush hour. It never occurred to me to check whether the casting itself had turned to sponge. True, we've got ice melt chemicals that will eat the chrome off hitch balls and the front rotors had been swapped six years prior but next time I'll be hunting for OEM from the cheapest possible channel...
 

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I never said OEM can't be better. YMMV. That's an ugly disk failure, but still lots cheaper than throwing a rod or transmission on a steep hill!
One of the great things about the internet and our exchanging information is we can now share what does (or not) work on our vans. Someone is sure to need brakes and tries an aftermarket product and let us know. I prevoulsly thanked 30 Ounce because he did that and I appreciate his knowledge and his willingness to make the effort to help us all out. I won't be paying what he paid and I'll be sure to have plenty of fluid on hand, due to his posting, thanks again. We need to do more of this, and perhaps have a FAQ section to document experience.
 

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I should point out that I got my pads from partsgeek.com, they were cheaper than the dealership by quite a bit. I agree that price does not always equal quality and really want to hear some feedback on those $40 pads. Parts Geek had some less expensive pads but they lacked the sensor wire.
 

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Even if brake replacement was free, IMO there are times when riding brakes is a bad idea. Signs reminding drivers to use a lower gear on long and steep descends are there for a reason. While brakes can overheat, the engine won't.
 

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So let's say we simply want to coast down a hill, going from "D" to manual shift will be ok?
I'm not familiar with automatic trans with manual mode.
Revving at 4500rpm down my usual safe/straight/no traffic/no speed traps small hills is quite scary/annoying.
Back when I was driving standard transmission, I was simply putting the engine to idle downhill..
 

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So let's say we simply want to coast down a hill, going from "D" to manual shift will be ok?
I'm not familiar with automatic trans with manual mode.
Revving at 4500rpm down my usual safe/straight/no traffic/no speed traps small hills is quite scary/annoying.
Back when I was driving standard transmission, I was simply putting the engine to idle downhill..
Yes, but it still won't give you full manual control.
 

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My Rav4 has decent control or at least has a button for that. I cannot see that it has any effect or function. If we wanted decent control why can’t we have such a button that enables it or lets us coast? I well remember the early 2 stroke Saab cars which freewheeled down hill and at the time they were considered some of the safest cars.
 

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So let's say we simply want to coast down a hill, going from "D" to manual shift will be ok?
I'm not familiar with automatic trans with manual mode.
Revving at 4500rpm down my usual safe/straight/no traffic/no speed traps small hills is quite scary/annoying.
Back when I was driving standard transmission, I was simply putting the engine to idle downhill..
Not sure where you are driving but the OP was talking about "mountains." You do NOT want to shift to neutral going down something like that. Let the engine rev to keep you from speeding up too much. It shouldn't harm it.

If you do need to slow down, as was said above do not ride the brakes. Hold them firm until you hit desired speed and the let up. If you accelerate again too much give them another firm hold. But always let up between holds to they can cool.

Safe driving everyone!
 
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