Going uphill slow down

[Mark S]

When I first test drove a Seneca I was disappointed in the performance so much so that I got on this forum and asked others about the lack of power. I was assured they had adequate power and that the one I drove had something wrong.

When mine arrived it was fine except it appeared it had no passing gear and on our first trip where we encountered hills it would not down shift until it was too late and lost momentum. Making matters more frustrating was my wife, a former first grade teacher, singing "I think I can, I think I can" on every climb. I felt I might have made a big mistake with the Seneca since my F150 Ecoboost pulling a 28' toy hauler had no problems on any hill climb.

Near the end of the trip I stopped at a Freightliner dealer Knoxville and with the assistance of Matt from Allison transmission had the transmission re-programmed so that the performance shift schedule is primary and economy mode is secondary. Our transmissions should have had a button on the dash to switch modes but Jayco opted not to do this to save a few dollars. Our units should have come from the factory programmed this way but they didn't.

After a few tweaks with the help of Matt I had a different vehicle. Climbing it would downshift at 1,700 rpm vs 1,400. One tweak Matt made was to raise the max rpm to upshift at about 2,500 vs 2,000 at full throttle. These two changes made a huge difference and no more singing "I think I can" on climbs from the passenger seat.

With all that being said, I realize that with the Jeep in tow, I am moving over 29,000 pounds with a 6.7 engine. Mine is very drivable now. My other vehicles have included a Corvette, a F150 3.5 Ecoboost, Harley Road Glide and other turbo vehicles. I like fast acceleration. I have never owned a vehicle where I said "Damn, this thing just has too much power".

I had to adjust my expectations, this this is a huge vehicle which is not going to accelerate fast. With the transmission reprogram it is very drivable now but by no means is it fast. Once I accepted that, my driving experience became much more enjoyable.

[GrayHawk51]

Originally Posted by jrwldr

Our 2017 TS slows to about 25 going up a a grade. How can we go faster?

I would also check out Five Star Tuning. https://5startuning.com/product/7015fs/

[Robbbyr]

Originally Posted by GrayHawk51

I would also check out Five Star Tuning. https://5startuning.com/product/7015fs/

I don't believe they offer a version for the Cummins/Allison combination in a Seneca.

[norty1]

I let gravity help me. Just before the bottom of a hill, I accelerate and the increase keeps me going up the next one. Passing trucks in the slow lane.

[McGintys924]

Originally Posted by repacs0103

One of my favorite movies of all time.

It was a great movie! It was just fitting since that line was as the truck was supposedly climbing a significant grade.

[Mark S]

Originally Posted by norty1

I let gravity help me. Just before the bottom of a hill, I accelerate and the increase keeps me going up the next one. Passing trucks in the slow lane.

Before the transmission reprogram I found if I approached a climb at 65 mph or higher I was fine, if under 65 mph I would lose my speed and would not downshift until it was too late.

[McGintys924]

I didn't have much trouble with the Seneca by itself, but it was on our first real vacation that I pulled 5000 lb worth of car and trailer that I was severely hampered. I found I needed to get up a lot of speed for any hill or I would be at 35 mph in a hurry.

Thinking the reprogram will help.

[jrwldr]

After listening to everyone, we are taking the Seneca in to have the tranny reprogramed.

I appreciate all the info!

Thank you