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Our first trip from on FLA to Vermont in our diy build
Much automatic shifting on hills is Normal?
Down hills engine rpm up while slowing van with foot off gas
PM 159
 

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The engine revving on downhills is both normal and desirable - it's called engine braking, and it keeps your brake rotors from heating up beyond their ability to stop the vehicle. It's also natural for the van to downshift going up a hill - the engine spins faster and makes more power, which is needed to lift the van up the hill.
 

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I have found that my PM does more with engine braking than any other vehicle I have ever owned. But it is a smooth and rev happy engine, so I'm sure its OK.
Its better than the old G30 van I used to have that would cook its rear brakes on a steep down hill. It had very little engine braking available and used to worry me on trips thru western Pa.
 
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2017 2500 HiTop 159 Cargo Van white.
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We just drove from Southern Oregon to Salida Colorado loaded with 4 dirt bikes and towing our 3400lbs trailer. Lots of shifting, especially at the 8-10,000 foot elevations.
35-40 mph climbing the big hills at 4-5000 rpm. I did a lot of manual shifting.
The only thing that really bugs me is when on cruise and it pops up to 6000 rpm before I can disengage cruise.
Everything worked very well even with temps often above 90 degrees.
 

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It's recommended to use the tow/haul setting in hilly terrain. Will make shifting less frequent (jumpy) in a lot of up and down, and keep the transmission cooler
 

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I doubt it's a 12 speed.
Anyway, the Ford is rwd.
The dodge is a fwd and only a 6 speed.
I knew all this before I bought mine and I'm not surprised by how it behaves or functions. Or disappointed.
 

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Hills confuse transmissions of all kinds. Try tow mode. You'll notice a difference. It won't react quite as fast and be much smoother shifting. It'll also help fluid temps from overheating. You shouldn't really 'feel' automatics shifting. That's a sign something is not working properly
 

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Also, it's not a $50k truck with an 8 or 10 spd rwd trans. It's a cheap Italian delivery van with a Chrysler v6 and 6spd fwd. Everyone knows that when they buy it. Or should.
Another option is to bump the shifter over and control the highest gear it can shift into. That keeps it from constantly shifting back/forth.
Just make it hold a gear until you get over the incline, or whatever the problem is.
It's called driving. It's what people had to do before computers made every decision for them.
 

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The engine braking does nothing but ruin gas mileage , the last time that I checked mine still had a brake pedal for when and if I wanted to slow down ! My 2018 Pro master 250 shifts more than any vehicle I've ever owned . Terrible design ! :mad:
Hi @butchsimones

I have read some of your posts, and you seem “Pro-Transit“ not Promaster

I could not find your intended use for your Promaster, but can understand your displeasure with the PM shifting. If you are considering a DIY Conversion & unhappy with your decision of trading in your Transit you might want to swap back before sinking time & money into your PM platform.

In my case I want it all for cheap, however I settled on the PM (lessor of the evils in my case). I love my PM so far, but I would like smoother shifting as well. Transit got crossed off my list very early in the process as the interior size (& shape) for a camper conversion was very important.
 

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I noticed since my "transmission solenoid pack recall" that the trans holds a lower gear longer and downshifts earlier.
 

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When first driving home with my new PM late last August the route took me down the Saluda Grade which is a very long drop off the Blue Ridge Escarpment to the foothills below. While in cruise the transmission downshifted + revved up and it seemed a bit extreme at the time, but over several long trips and 15K+ miles later I've grown to appreciate it.

Unless pressing the throttle it doesn't use any more gas than coasting and if I've got a pretty good load it definitely feels safer than careening down steep hills and around sharp downhill turns, or heating up the brakes needlessly to maintain safe speeds. As some have mentioned, for the money I'm continually impressed with how the PM drives, handles and inspires confidence in my daily use.
 

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I've noticed that it shifts more in cruise control. I've gotten to where I just leave it off and can manage the shifting better with the gas pedal. Engine brake shifting is still a little difficult to overcome. Giving it a little more gas pedal on the downhill will keep it from downshifting but it's not always ideal.
 

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I don't think a cargo van should hold 5k rpm for extended amounts of time when on a hill that's on a major interstate and why does the cruise control make the van accelerate hard when climbing! Even in tow mode. The powerband and shifting programs don't work very well if you ask me. My next van will be a diesel and hopefully the increase in torque will work better.
 

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I don't think a cargo van should hold 5k rpm for extended amounts of time when on a hill that's on a major interstate and why does the cruise control make the van accelerate hard when climbing! Even in tow mode. The powerband and shifting programs don't work very well if you ask me. My next van will be a diesel and hopefully the increase in torque will work better.
It only does that when the power required to maintain the speed requires 5000 rpm. The engine reaches peak horsepower at 6350 rpm, so whatever power that is required to hold the speed at the set speed must call for about 5000 rpm. It is generally better for the engine to turn higher rpm than to struggle at low rpm. The risk of pre-detonation is lower at higher rpms given the increased piston speed and timing curve generally used.

The computer knows that if it downshifts it does not have enough power at the lower rpm to maintain speed. So it holds the gear and maintains speed. You can take it off cruise control and slow down, or set the cruise control for a lower speed if you don't like it, but you can't magically force the engine to make enough power at a lower rpm to maintain the speed up a hill. So you turn the rpms and make the needed power, or reduce the needed power by going slower. Nothing wrong with either one, but if you leave the cruise control on it will attempt to maintain the set speed as it is programmed to do.

I drove a Citroen C3 across italy through the mountains, I can assure you that this tiny passenger car also required 5000 rpm or more to go up the hills. The difference it that it had a 5 speed and I have to downshift manually. Until I figured that turning off the air conditioning on the uphill climbs I would end up in second gear turning 6000 rpm just to get up the hill (it was a 68 horsepower car that makes peak horsepower at 6000 rpm). Once I turned the air conditioner compressor off I still needed 6000 rpm, but was able to use 4th gear and not risk getting run over by the other cars on the road. The air conditioner still blew cold for a while as the evaporator warmed up and as soon as I got to the top I turned it back on and it cooled back down on the downhill runs.
 

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2019 Promaster Silver 1500 low roof
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Hills confuse transmissions of all kinds. Try tow mode. You'll notice a difference. It won't react quite as fast and be much smoother shifting. It'll also help fluid temps from overheating. You shouldn't really 'feel' automatics shifting. That's a sign something is not working properly
So far I really haven't driven my PM (other than a total of 12 miles on flat land to get my running boards installed) but I live in the 'mountains' (well, hills but don't let anyone born in this area know I said that). I was told by the dealer that I should use the Tow mode for going up hills .. should I use it downhill too?

If I lived in TX again I might use cruise control once in a while but I don't. I have often driven 2k miles at a time with my current truck and never even remembered it was there. Not a fan but I have it on this van so hope I never get to hear what the engine sounds like/what rpm it goes to in that mode on any hill. I'm used to my Ridgeline running at 2k-2.5k rpm .. rarely ever seen it higher even on hills.

I can tell this PM is going to take some getting used to. I seem to have a problem with just finding the shift stick .. keep turning on the windshield washer instead. :ROFLMAO:
 

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Ridgeline is a lighter vehicle with a smaller frontal area. It simply doesn't require as much power to maintain speed up a hill. Expect higher RPMs and just be ok with it. No reason to fear the engine turning, they were made to turn.

Modern engines are well balanced and have lighter reciprocating assemblies. They happily turn at speeds I would never dream of taking some of my older cars. If I ever hit 4000 rpm in my GMC with a big block 402 I fear the carnage that would ensue, but my Subaru barely makes much power below 4000 and my promaster happily turns 5000+ when it needs the power. A lot of use tend to judge modern machines by the vehicles we learned to drive in and drove in the past. They aren't the same.

Let it rev
 

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I'd use tow mode when a substantial amount of travel is on an incline, both up and down. One of the things the mode does is changes clutch points to shift more gradually than normal. When weighed down or on slopes, staying in a gear longer helps the transmission from overworking by changing gears frequently. You don't benefit from rapid gear changes when heavy or when gravity is an additional factor in the same way a lighter vehicle on flat terrain does and higher rpms are less stressful than higher torque on the transmission.
 

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Yep, different engines different applications all use rpms in vastly different manners. The Pentastar in the Promaster is a twin over head cam V6 and designed to generate more power and torque at higher rpms. Arguably not the best solution for a truck or a van, but it’s a strong well tested engine. I have a Lotus that has about the same horsepower as an economy car literally until over 6,000 rpm - when all **** breaks loose and it goes like stink to 8,000 rpm. My Trailblazer SS with the 6.0 V8 liked it between 4k and 5k rpms. If you need the power let the Promaster rev, as other said, it won’t hurt it and is actually better than lugging the engine.
 

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Yep, different engines different applications all use rpms in vastly different manners. The Pentastar in the Promaster is a twin over head cam V6 and designed to generate more power and torque at higher rpms. Arguably not the best solution for a truck or a van, but it’s a strong well tested engine. I have a Lotus that has about the same horsepower as an economy car literally until over 6,000 rpm - when all **** breaks loose and it goes like stink to 8,000 rpm. My Trailblazer SS with the 6.0 V8 liked it between 4k and 5k rpms. If you need the power let the Promaster rev, as other said, it won’t hurt it and is actually better than lugging the engine.
I had a Kawasaki sportbike that made bicycle like power below 8000 rpm, but from 8000 - 14000 rpm... wow
 
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