Manual Shifting ASI transmission

[ScottP]

Hey All,

I’m curious how many of you AI owners manually shift your transmission?

Upshift, downshift

Utilizing engine braking down a steep grade?

And if so, how often?

Hourly?
Daily?
Weekly?
Monthly?

Never?

[WillieJ]

Often. On long upgrades, and to control speed on downgrades. Some of the OBD monitoring devices, in my case Ultragauge, can show “engine load”. I downshift when it hits 85% on a long upgrade. There is some discussion of this on https://sprinter-source.com/forum/ which is dedicated to Sprinters of all varieties.

[Pahaska]

Seldom.

I used it initially to be sure of how it worked, but in 20 months, I have only downshifted one time and that was on crossing the mountain at 3 Sticks in eastern Oklahoma. Some really steep grades with switchbacks on the north side.

I came down that mountain behind an 18-wheeler who was burning his brakes to the degree that we could smell them burning a hundred yards back. I kept waiting for him to lose it and pile up on a curve, but he made it down safely. By downshifting, I barely needed to use my brakes.

[Alex AVI]

Originally Posted by ScottP

Hey All,

I’m curious how many of you AI owners manually shift your transmission?

Upshift, downshift

Utilizing engine braking down a steep grade?

And if so, how often?

Hourly?
Daily?
Weekly?
Monthly?

Never?

SCOTTP - Same answer as JOHN. Only difference in my case is I use it at least once or so every trip, only to test things out. Ok, admittedly sometimes just to "play with the equipment" and pretend I am in a nimble Porsche Tiptronic . . . the closest I will ever be to driving a Porsche. On very rare occasions when I don't feel like tapping brakes and unduly scare traffic behind me. Some grades like Cajon Pass near Victorville, Townes Pass in Death Valley, Kingsbury Grade near Lake Tahoe, Carson Pass near Markleeville - all can propel me to 85mph if I don't downshift. Very well managed descents in a car as they are non-technical descents but need manual intervention in AI.

[Tronadora]

I manually downshift on all steep descents and sometimes on ascents when I've lost patience waiting for the auto downshift to occur.

I've also been more and more doing the 3-second hold-to-lock into manual at stop lights. The AI always auto-shifts into Second without a proper torque converter lockup in First. This produces two undesirable results... anemic acceleration due to arriving in second at too low RPM (it seems to skip right over First and dumps me into Second)... and... if I'm needing some acceleration at that precious moment, I've been feeling shuddering of the transmission, like it's laboring (hopefully not having real internal issues).

So the 3sec hold trick lets me launch in first and I can quickly flick the lever right to let it shift into Second rather quickly so I'm not racing the engine. Or give it two flicks and I'm back in full Auto mode. No shuddering. I'm happy, and the guy behind me is happy.

I do this hold in First about 10% of the time, and it is increasing.

[Lily&Me]

I also manually downshift on all steep descents, so as often as necessary on any given trip.

Maggie

[InterBlog]

Downshift in the mountains all the time. The thing has four manual gears - gotta use ‘em.

[Lotus54]

Occasionally downshift going up steep grades- most of the time it shifts just fine by itseft and keeps a good rpm (I hear the V6 doesn’t do that as well?)

Certainly downshift going down grades. I use mine for day trips a lot- often on steep gravel roads. Sometimes I downshift going up on those also- depending. Keeping it from shifting up and down automatically.

mark

[Boxster1971]

I manually shift routinely to prevent the engine from lugging below 2,000 RPM when I don't want to press the accelerator to downshift and accelerate. The 5-speed with V-6 is notorious for running the engine at 100% load and not downshifting. I also use an Ultra-Gauge to monitor load and downshift up steep grades if the transmission doesn't do it automatically. I down shift for steep downgrades to keep speed under control and save the brakes.

[ScottP]

Originally Posted by ScottP

Hey All,

I’m curious how many of you AI owners manually shift your transmission?

Upshift, downshift

Utilizing engine braking down a steep grade?

And if so, how often?

Hourly?
Daily?
Weekly?
Monthly?

Never?

Fascinating!!!

While some of the “manual shifting” undertaken by operators may depend on your terrain, altitude, and load such as trailer towing. I suspect it’s also about awareness, philosophy and performance expectations.

For us - manual shifting is our standard operating procedure..

We’re often in hilly/mountainous terrain, we frequently tow a load of a single axel bicycle / motorbike trailer (1,000-2,000 lbs). But even when we’re empty with no trailer, and on level ground we shift manually up and down. We feel we avoid the dreaded shudder from the “too quick” upshift (1st to 2nd), and we can control the sheer weight of the vehicle more effectively with quick downshifts plus steady braking.

BC trip report:
For example, the panorama photo of the curvy road cut into the side of that mountain, was navigated by us in our ASI plus trailer and motorbikes. Hard to imagine doing it without downshifting / upshifting.

It’s second nature to us at this point, and I’m surprised by the different way we all operate our rigs.

Coming through the pass in 2016 from the West and into Jackson Hole WY, I followed a silver ASI observing (and smelling the brakes) and it appeared they just held their brakes through the entire descent.

Ugh


Anyway ... it’s an interesting conversation.

[Andrew T]

What I suggest to customers is that if you are using the brakes to control speed going down hill you are in the wrong gear and need to shift down.

Where we also manually shift down is highway cruising with many of the turbocharged or supercharged engines gas and diesel. We find many of these will tow in top gear but they are deep into boost doing so. Shifting back one gear gives better fuel economy and reduces exhaust temperatures etc. Something you can play with on long flat stretches. If you have a digital fuel economy read out it is easy to see the difference.

I hope this helps.

Andy

[mrfixit51]

Originally Posted by Boxster1971

I manually shift routinely to prevent the engine from lugging below 2,000 RPM when I don't want to press the accelerator to downshift and accelerate. The 5-speed with V-6 is notorious for running the engine at 100% load and not downshifting. I also use an Ultra-Gauge to monitor load and downshift up steep grades if the transmission doesn't do it automatically. I down shift for steep downgrades to keep speed under control and save the brakes.

I haul a vintage 23' Travelux( more like an Avion) with my diesel Benz. I do shift regularly on hilly terrain. I watch the rpm as you said and will keep in in the 23-2500 rpm range. The 3l turbo, 7 speed, does have the power at 2000, but i prefer to bring up the revs, which is better for dpf to keep things cleaner for the engine output.

[Boxster1971]

Originally Posted by mrfixit51

I haul a vintage 23' Travelux( more like an Avion) with my diesel Benz. I do shift regularly on hilly terrain. I watch the rpm as you said and will keep in in the 23-2500 rpm range. The 3l turbo, 7 speed, does have the power at 2000, but i prefer to bring up the revs, which is better for dpf to keep things cleaner for the engine output.

The 3.0 liter V-6 with 7-speed is a much better combination than what has been offered in Sprinters. Fortunately the new 2019 Sprinters will have the V-6 + 7-speed combo. It will be a big improvement.