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DayCab Vs Sleeper - AHMLLC - 05-27-2018

I've driven a daycab and sleeper 2014 Cascadias with the same exact setup and for some odd reason the day cab is much better on gas and visits the shop less than the sleeper. Both trucks run the same amount of miles and travel on the same roads.

MY question:

Why is the day cab better on fuel? Weight plays a factor? Less electrical components? Just trying to learn more. Thank you


RE: DayCab Vs Sleeper - Waterloo - 05-27-2018

Day cabs are normally geared differently than an OTR sleeper. Best fuel economy I have ever gotten consistently across the board was in a little 96 Volvo with 3:90 gearing. 8.3 mpg pulling a 53’ step deck van. Seriously thinking of going that route in my ProStar.


RE: DayCab Vs Sleeper - AHMLLC - 05-27-2018

The lower the gear ratio the better?


RE: DayCab Vs Sleeper - Waterloo - 05-27-2018

Personally, I would not have anything less than 3:55 gearing, 3:75 would be better, 3:90 would be the bomb if everything matches up. But, for fuel economy you have to keep your foot out of it. I ran that little 360hp Volvo, 9 speed, at 60-63 mph and she was consistently over 8 mpgs. Didn’t matter the conditions, she was consistent across the board.

Right now I’m running 3:34 gearing and it is terrible for what I do. 3:75 -3:90 would be ideal. I’m not racing up and down the road at 70+ mph. The gearing is to high for what I do, a lot of stop and go, lugs the hell out of the motor as the drop in rpms is so severe between shifts. I’m fast, but not that fast. I have wanted to swap out the boxes since I bought the truck, but other issues have prevented that.


RE: DayCab Vs Sleeper - Rawze - 05-28-2018

(05-27-2018 )AHMLLC Wrote:  The lower the gear ratio the better?

It all depends on your application.
http://rawze.com/forums/showthread.php?tid=2015&pid=17353#pid17353


RE: DayCab Vs Sleeper - Chamberpains - 05-28-2018

Sleepers add Extra weight to the cab, extra electrical, piping, suspension, personal living items, cabinets all swinging around and crashing up and down all day everyday on the chassis adds to problems.

As for gearing, there is no "more in 1 direction" to go in that makes it better. You have to pick the proper ratio to the RPM range you and your operation needs to run in. Some info on your operation (truck type, gears in trans, weight when loaded and how often, terrain operating in, part of the country or countries you operate in and majority of road type you operate on) and someone on here could probably help you pick a good rear gear ratio.


RE: DayCab Vs Sleeper - Volvo8873 - 05-28-2018

IMO you only need a sleeper if you are actually going to use a sleeper. Otherwise a daycab is no doubt easier especially to deal with. Sometimes when I run my day cab truck I run into a situation were it might be a few hours of sitting. This is were this comes into play http://www.daycablounger.com/home.html it looks really stupid to some but it does work very well.


RE: DayCab Vs Sleeper - Chamberpains - 05-29-2018

Lots of trucks used to come with just a bed (bunk) behind the seats. Do they even make them anymore? Im curious for when the day comes that I want or need to be home more.