T680 questions.

[Lonestar10]

I'm floating the idea of getting another truck and I've found a decently specced non fleet 2015 t680 450k miles cm2350 cpl 3937, 18sp, 3.36s, vit interior, 238wb, 76in sleeper, had an Apu.
So here's what I wonder below.
In door jam is a sticker with scale weight 17900lbs is that what the truck scaled with 0 fuel?

Reason I ask is my Lonestar filled to brim is around 23,000lbs and all my securement gear is housed in trailer boxes.
if I could drop say 3000-3500 lbs empty weight with full tanks my life would be so much easier.

I told the dealer if they put on all new low rr virgin rubber bridge or mich, put on a new fuel pump, change the oil and barring my "mechanics" inspection I would give them asking price
I plan to get hooked up to it with insite and run every test I can to check the engine over before they do any work to it.

[Rawze]

should also replace those rears with something more decent.

[Lonestar10]

rears are about another 6-7gs for new based off my lonestar ones i replaced i would probably do it but later down the road first would want to get the truck up and rolling making the monies and start saving for the inframe that would becoming in 200-300 miles based on average. but who knows with some proper reprogramming to shut off the EGR and possibly the SCR if thats possible ill the DPF till it starts wanting to cause issues. or just get rid of it all right off the bat. im in the boonies so no worries about the canadian and californian communists.

[Mattman]

2015 T660 mid roof isx15, 13 speed, no apu think my wheel base is just longer than you mentioned. Have 135 gallon fuel tanks. I weigh between 19,000 to almost 20,000 depending on how much fuel I have on.

[Mattman]

My door sticker says 17,672 for weight.
Not exact as the truck you are looking at but should be close.

I have 3.36 gears and 295/75R22.5 tires. Wish I had 3.55 gears I have to be going fast to use top gear while loaded. Mine is 450hp 1650 torque.

[Nilao]

That door weight is the dry weight

[SquareOne]

(02-15-2020 )Lonestar10 Wrote:  ...Reason I ask is my Lonestar filled to brim is around 23,000lbs ...

Man, that seems heavy....are the Prostars the same way, or is the Lonestar a heavier spec truck?

[Chamberpains]

23k is really heavy. My 9400i is a touch over 20,000 with 300 gal of fuel and all my chains and gear in the headache rack.

[JimT]

(02-15-2020 )Mattman Wrote:  My door sticker says 17,672 for weight.
Not exact as the truck you are looking at but should be close.

I have 3.36 gears and 295/75R22.5 tires. Wish I had 3.55 gears I have to be going fast to use top gear while loaded. Mine is 450hp 1650 torque.

I feel you. I have 3.42 rears with a 13 speed. 63 mph in 13th puts the engine at 1350rpm. 1450rpm puts me at 68. If I drop down to direct (12th) then 1550rpm puts me at 62mph. 1800 in direct puts me about 70mph. 1350rpm gives me the highest mpg but is only doable when light and on relatively flat ground, high 7's to low 8's. 1450rpm (at 68 mph) still gives me 7's for fuel mileage even when loaded around 70k. 1550 in direct (62 mph) isn't bad but averages about .5-.75 mpg less then 1450.

Of course, all those numbers are with cruise control set and NOT climbing any significant hills. Prior to finding this site I would keep my operating range 1300-1500, rarely ever hitting 1600rpm. If I let it drop down to about 1250 I could feel it lugging, learned pretty quick on my own to stay above that. (Yes, I know, I also cringe now at the thought) NOW I KNOW BETTER and keep normal operation between 1400-1600 with grades and acceleration hitting 1700-1800 when appropriate. Only time I run below 1450 is with the boost under 10psi and at 1350 I keep the boost to 5psi max. If that can't hold I downshift.

Still getting the hang of it and finding the sweet spots, but without the dpf active my fuel mileage is good. Once the DPF starts to regen though, I lose AT LEAST 1 mpg off my trip average. Despite all the work I've done to get this system operating properly, I think it's time to cut my loses. I estimate the cost of continued maintenance along with the extra fuel usage will cost me about $15k per year to keep some air clean...