Seneca M2 power uprate

[SloPoke]

Originally Posted by AaronL

Interesting feedback here. I've been thinking about this upgrade also. Not sure I need it but I've not driven one with more power so hard to say. I have a 2014 with the OD lockout switch and I've NEVER used it. Transmission seems to shift up and down just fine. In fact, on the upshifts, I typically lift slightly off the pedal near 1800 RPM so it shifts sooner.

all: don't think that I am not interested in more power (Tim the tool man <grunt> sound ) and I have done some crazy performance engine mods in my younger years... Some I still own and drive today. I would be awesomely excitedly happy to be able to run up our Parleys Canyon - 6% grade fully loaded running at 33,000LBS and stay in the second lane at 65+MPH. but even if I could.. I doubt that i would do it, since I would not consider going down that pass at 65+MPH either. There are enough people weaving in / out of lanes going up the pass in the mad dash to make it to the top... I'm more than happy staying in the truck passing lane passing every truck with a load and most RV's in the truck passing lane. Our Seneca does sometimes get to 2200RPM when I lock out the overdrive and are passing, but that is about our limit

Originally Posted by AaronL

Even on the Cajon Pass during the same trip heading north towards Vegas, LONG 6% grades again and nothing lower than 50 MPH. Granted, I'm WOT at that point but it pulls just fine. Have passed plenty of V10 powered Class A's in these situations. So, wondering, would it be good to have more power? Maybe but I think I'd want more torque than HP - and geared properly - for mountain climbing. So does it sound like I have the "normal" Allison shift mapping?

Maybe we should take a run down to Laughlin/Bullhead for a weekend... and on the way back - run up the Kingman grade together - just for comparisons... I'm wondering if we have the same setup? ... and cold beers after backing both Seneca's in the driveway at the new house to compare the differences????

OK... I'll make the invite open to other Seneca owners... too! Google the SR68 Kingman grade from Bullhead City AZ to Kingman AZ to see the details.

[AaronL]

Tempting, Steve! So, 7% and SAE set a standard for car towing using this road. Very interesting! And beers you say?!? Hmmm..



I'm with you though - I think I have enough power for what I'm towing and the part of the country I'm driving most.

[AaronL]

Originally Posted by SloPoke

Maybe we should take a run down to Laughlin/Bullhead for a weekend... and on the way back - run up the Kingman grade together - just for comparisons... I'm wondering if we have the same setup? ... and cold beers after backing both Seneca's in the driveway at the new house to compare the differences????

So I saw a link which took me to this video which I actually watched a few weeks ago. Didn't know about the test road you mentioned but he references it in the video! If you want to geek out on general engineering stuff related to cars, this guy has a pretty cool site!

https://www.youtube.com/watch?v=iPhMnj1F-Lc

[Mark S]

We are out on our first trip pulling the Jeep since having the uprate done and I have some “quantitive” results. While driving at 65 mph we came up on a truck in the right lane going a bit slower. I pull in the left lane and accelerate from 65 to about 75 and safely pass. My Chief Navigation Officer looks at me and says “wow, I’ve never felt this thing accelerate like that before.” We have come a long way from “I thing we can, I think we can”.

I monitored the engine and transmission temps as well as Mpg and there were no changes.

Note: my normal cruising speed is about 62-63 mph and I have no desire to drive at 75. This high speed test was performed solely to provide information to members of this group.

[Bruceter]

Thanks for the update and review Mark. After I get the O/D lock out switch installed the engine update will be next on the list!

Bruce

[Sam]

Mark, my experience is nearly identical to yours. I now have nearly 9,000 miles on my Seneca since the performance uprate last August an enjoy the added performance.

Immediately afterwards, I made arrangements at an authorized Allison service center to have the transmission reprogrammed to the performance setting. After the tech contacted Allison and provided my vin and engine numbers Allison said mine had the highest performance rating. I was puzzled, however, after Robby explained how Senecas had one or the other transmission programs it became clear why mine had the performance setting.

Further, you said that you have reached 2,500 RPM before the trans shifts since the modification. I have reached almost 2,600 RPM on several upgrades before the trans shifts. Clearly this confirms I have the upgraded trans modification.

Thanks for your input, that along with what Robby has said clears up questions that I have had. Sam

[MD3]

Originally Posted by Bruceter

Thanks for the update and review Mark. After I get the O/D lock out switch installed the engine update will be next on the list!

Bruce

I'd like to hear more about this process once you get it done.
I would like to have this option on our 2018.


_

[Bruceter]

Originally Posted by MD3

I'd like to hear more about this process once you get it done.
I would like to have this option on our 2018.


_

Will do, going into Jayco Dealer March 7th for some warranty work then hopefully getting it into Allison Trans for the O/D switch.

Bruce

[memphis02]

Originally Posted by Mark S

It is definitely seems a bit quicker off the line.

I had to chuckle when I saw this statement! What was your 60' time?! LOL

[jdd]

We have a 2017 37TS. I spoke with Cummins and our unit can be uprated but I am not having any luck with getting the warranty charge waved ($500 +/-). In your alls opinion is this uprate worth approximately $1,000.

[jcs1880]

I just had the uprate done and it cost me $360. My transmission came with the proper programming. It is well worth what I spent, and is nice to have a manly improvement that my wife also enjoys. As for spending $1k, I would look for a way around the warranty charge. Depends on your level of "the need for speed", or in this case "the need for power".

[RVermont]

Originally Posted by jdd

We have a 2017 37TS. I spoke with Cummins and our unit can be uprated but I am not having any luck with getting the warranty charge waved ($500 +/-). In your alls opinion is this uprate worth approximately $1,000.

Did you use a cummins specific location or a truck service center that offers work on cummins. Not sure why there is such a wide range of pricing on this change. My unit is a 2018 and there was no warranty charge. Service done at Albany ny Cummins shop.

Call around and maybe you can find a location that will be a nice stop on a future trip.

[jdd]

I did talk to the local Cummins office and had no luck, I am now working with a local shop and they think the warranty uncharge can be waved. Haven't gotten final word as of yet, but hopeful because I would really like to do the uprate.

Thanks for all the input. Stay tuned!

[johnboy]

Hello out there in Seneca land. I too had the transmission upgraded in 2018 and WHAT a difference. I live in northern CO, just driving it back from TransWest (where the upgrade was performed). Now I have not driven it up in the CO mountains since this upgrade I did drive it to western, NY and to Branson, MO. The hills leading into Branson are a step incline its like being on a roller coaster. Up-Down-UpDown.... Pulling a Chevy Sonci on a Dolly had no problems. This year our only trip was to West Yellowstone and the Seneca did excellent climbing the hills and passes on our way there. Coming back The summit between Laramie and Cheyenne (elevation 8,640') is the highest point on the transcontinental I-80 Route. At Cheyenne. I was passing semis and RV's (TT, couple Motorhomes) I was doing between 45-60 miles up this pass. We did go to Gunnison,CO B4 the upgrade and I wish I had the upgrade before that trip. But then again the Seneca did okay not the greatest. I was not towing a vehicle either. I plan I calling Transwest soon to see if they can do the Engine upgrade. We have a 2017 37TS model.

[jdd]

Finally ordered the engine uprate, we had it completed months ago preparing for a West coast trip, then Covid screwed everything up so we haven't had a chance to really test the difference. We're planning to leave on the same trip mid September. Also, when they reporgrammed the engine I had them check the transmission and it is in performance mode. Is the the upgrade/mode you all are speaking of or is there some other change recommended?
Thanks agin for the responses!

JD

[Mark S]

I am on my first real trip since the engine uprate. I had the transmission reprogram three years ago and last year I added the OD lockout switch, both have made a big difference. I had the uprate done in February of this year.

We have traveled from south Florida and tonight we are in Amarillo Tx.
The engine uprate has made a nice difference so far and we haven’t hit the mountains yet.

On inclines the transmission is not down shifting anywhere near as much as it did before. Last year on the same route I had engaged the OD lock out multiple times by now to maintain speed on some inclines, haven’t needed to lockout once so far. Passing power is much improved.

Transmission fluid and coolant temperature have not changed and mpg is the same. Dollar for dollar this is the best improvement so far.

Tomorrow or Tuesday we hit the mountains and I will report my experience.

[jdd]

What type of shop did you have the OD lock out installed. I spoke to a Freightliner dealer and an Allison shop and both look at me like I have a third eye. I need to find someone reliable to speak to about adding the lock out.

[Mark S]

Originally Posted by jdd

What type of shop did you have the OD lock out installed. I spoke to a Freightliner dealer and an Allison shop and both look at me like I have a third eye. I need to find someone reliable to speak to about adding the lock out.

My local Freightliner dealer in Fort Lauderdale did mine. They had never done one before and it was like $1,400 and took them about three weeks. I was not a happy camper and would not recommend them.

Apparently it needs to be a Freightliner shop as they need to cut into the Freightliner wiring harnesses and program. The local Allison shop would not do mine.

Try to find a shop that has done one before.

[jdd]

Thanks, I will keep looking

[SloPoke]

Originally Posted by Mark S

I am on my first real trip since the engine uprate. I had the transmission reprogram three years ago and last year I added the OD lockout switch, both have made a big difference. I had the uprate done in February of this year.

We have traveled from south Florida and tonight we are in Amarillo Tx.
The engine uprate has made a nice difference so far and we haven’t hit the mountains yet.

On inclines the transmission is not down shifting anywhere near as much as it did before. Last year on the same route I had engaged the OD lock out multiple times by now to maintain speed on some inclines, haven’t needed to lockout once so far. Passing power is much improved.

Transmission fluid and coolant temperature have not changed and mpg is the same. Dollar for dollar this is the best improvement so far.

Tomorrow or Tuesday we hit the mountains and I will report my experience.

We are looking for that update... Since our chassis warranty is now expired, it is time to consider this - and seeing your smiling faces out here in the west.. Dang if it has not gotten hot all of a sudden.. 100F today! (but a dry heat)