Ordering or buying new Volvo VNL780. Suggestions?

I shift is supposed to be a good transmission. The ishift transmission controls the engine for better MPG. Eaton is the older style. The clutch mechanicals are better on the newer moderator auto-shift transmission like Ishift or Detroit transmission if you had Freightliner

 

What tire size do you want to run? 3.55s with a direct drive transmission and 24.5 tires would have you at 1500rpm at 55mph. 1900 at 70mph. If you want to be able to run 55-70, you'd be best with a 2.64 or 2.79 or something in that range depending on your desired tire size with an 18 double over.

 

If you go with the Volvo and get the XE package and the ishift with 2:64 rears I think running at 65 mph your rpm's will be around 1000.
Think I read that somewhere.
Plus I'm on my 2nd Volvo with the I shift,and I will not go back to a stick. I started driving a truck in 1978 and I was one of these die hard I'm never going to drive an automatic truck, now you couldn't give me a stick shift.

 

Your initial specs are an "old school" spec. I'd listen to the advice, I have an M-drive (I-shift for mack) and love it. 2.64 on an I-Shift is direct drive I believe. If you're after efficiency that is what you need, also get the wheel base right keep the trailer as close as you can to the back of the cab.

 

If you're set on going with Volvo, I would follow their advice. Seems like your stumped over going with your feelings vs Volvos recommendations. Volvo has a lot of experience with the idrive, let them build it to your requirements, rpm + mpg, at the speeds you expect to go. Also note that they have significant market share in Europe, they are probably the most experienced brand when it comes to auto trans. I would also consider buying an extended warranty for the longest term available.

 

I could see an 18 speed only if the truck was going to be used in a wide variety of applications. Heavy, sometimes permitted heavy, off road( construction sites etc) or over dimensional, running 48 states.
If you are on road, consistently 75-80 K gross the current thinking is direct drive top gear ( straight through the transmission, no gears causing resistance) and a rear end final drive ratio that is appropriate for the intended geography and average speeds operated.
Most of the in stock Volvos are spec'ed for your intended use. 80% of them have the ishift the rest have 13 speeds. That should tell you something about where this industry is headed. Final ratios are mostly 2.64 some are 3.08. The ishift is available with either a direct top gear or an overdrive top gear, hence the difference in available rears.
A good knowledgeable truck salesman who has sold these units for a while is your best asset, let him show you what the factory recommendations are and how he comes to his conclusion about the spec's for your application. If he is BSing you, move to another.
You are absolutely in the drivers seat buying a truck now, either in stock or ordered. Volvo just laid off their entire second shift last month in Virginia, 3 layoff in about 12 months.

 

Warranty Warranty Warranty
I never took warranty on a truck before until this '12 780, D-13, 18 manual. A shop foreman convinced me and am I ever glad he did. I took engine, aftertreatment and harness, which includes all sensors. The cost was 7400 bucks but added to overall financing was minimal per month. I got 8 times that back over 5 years. Injectors and cups twice,harness, EGR coolers,numerous sensors and aftertreatment issues coming out the ying yang. I'm pretty sure I got a Friday or Monday truck but it never cost me a dime for a quart of nothing. Over 40 years I never believed in extended warranty, but this new stuff now I wouldn't hesitate. Don't care what Dr Rutherford says.

 

The only time you are going use all 18 gears is to "split" the gears in low range is at speeds below 20 mph. And that is only necessary in very trying conditions. In your application you are going to use the 18 speed as a very expensive and complicated 13 speed almost all the time.
If weight is an issue, the aluminum 5th wheel is an $option. But in order to do the weight saving thing right there are a dozen or more other items that Volvo can substitute. Take a look at the way the 730's are spec'ed when guys order them to use with tankers, and see if you can live with them on a 780. Weight saving options drive up the cost, you get to decide when you write the check how important they are. Even if you pull out all the stops the difference will be less than 1500 lbs, and that is mostly from using smaller fuel tanks with less capacity.
To get an idea of how complex the topic of mating drivetrain components to proposed application, take a look at this spec' sheet of available transmissions from Eaton Fuller. Just look at the available ratios for just the 13 speed/18 speeds in either manual or autoshift. It is mind boggling. Add the torque characteristics of the engine and the rear end ratio and you have a full time job just figuring it all out.
http://www.eaton.com/EN/rr/ProductsServices/ProductsbyCategory/Transmissions/PCT_486870