Hi, everybody. A new member here... I just got a 2015 Mack CXU613 four axle truck to pull my 55 ton float trailer. This new 505C+ MP8 engine is rated for 1860 Lb-Ft torque in all gears; and makes 505 HP at 1500-1700 RPM. 14.6K front axle; 20K pusher, 46K drives, 18 speed manual Eaton, 3.91 rears, 11R22.5 rubber. The way the truck is spec'ed I'm at 1404 RPM at 60 MPH. My goal is to stick to a 7 axle rig and haul loads up to 90,000 Lb in payload weight throughout US and Canada. I just finished a couple of first loads and the truck doesn't pull all that well. I cannot change the truck but I can upgrade the axle ratio. A friend of mine has a pre-emissions FTL with a 12.8 L Detroit and he does okay with 4.33 rears and 24.5 rubber, which is the same as 4.11 with my 11R22.5 rubber. Would be interested to hear advice from people that run trucks with small engines (up to 13 L) in heavy haul operations (up to 132K Lb gross). Thanks!
first of all it's not a mack it's a p.o.s. volvo with a bulldog on the hood . my first thought while reading your post was it's geared to high .whats top speed about 90 MPH. does it pull better in a lower gear with higher RPM's if you have a good dealer that knows what he's doing have them check the throttle response make shure it's set to instance how does it pull with cruise control on. with the computer controlled engines one setting can make all the difference especially when loaded heavy that won't normally show up when hauling legal loads
you lost me right after that phrase .. i'm seeking advice from people who use small engines in heavy haul operations, makes and models don't matter. please refrain from posting any more spam/flak/trolling in this thread. you clearly have nothing to contribute beyond that.
volvo bought mack about 2007 now they are all volvo except for the dog on the hood.if you open the hood and look at part #'s you will see that. I have 10+ of the purebred mack's and two 2007 pos crossbreeds with the mp7 405. since i have nothing to contribute I won't say any thing else :notworthy