Hello and looking for a bit of info

[dave41855]

My name is Dave and I live in Vermont. Owned my own R686ST and hauled logs, pulp, woodchips and some lumber mostly in New England. For the most part my adventures in trucking were all good, that is, until the last 2 or 3 years after the DOT began to clamp down on us!! 19 years behind the wheel and, thankfully, never had any type of fender-bender at all.

Not long ago, a couple of us "ole boys" were sitting on the porch and as usual, the topic turned to trucks. And this brings me to my question. How did Mack TRUELY  measure a trucks horsepower??  I had been told years ago they rated it at the rear wheels and not at the flywheel. Always figured that's why my little 300+ could outpull a 350 Cummins up Mendon Mountain grossing 90,000 with hemlock for Glens Falls NY. Any idea there fellas???

Dave in Vermont

The attached is my old truck as she looks today with a dump body on it. Still going strong and working just about every day!

[hatcity]

Welcome aboard

the truck-"She's a beaut Clark"

[j hancock]

Good looking rig!

Mack engines are rated at the flywheel.  Mack engines make some pretty good torque and torque gets things done.

[B MACK]

Nice R Dave.   I too have always heard that MACK hp is rated to the ground?? 

[TeamsterGrrrl]

If they weren't rated at the rear wheels, I suspect a lot of Mack engines were underrated. For example, the 11 liter 285 HP Maxidynes we had at the Postal Service gained 4 valve heads and grew to 12 liters, yet the HP rating only increased to 300? Even in high gear hill pulling where the Allison automatic was no advantage, those trucks would pull with Cummins and other 350s with similar loads. We also had some Volvo/Whites with the supposedly equal 300 HP L10 Cummins, and the 300 Macks would run away from them.

[dave41855]

3 hours ago, TeamsterGrrrl said:

If they weren't rated at the rear wheels, I suspect a lot of Mack engines were underrated. For example, the 11 liter 285 HP Maxidynes we had at the Postal Service gained 4 valve heads and grew to 12 liters, yet the HP rating only increased to 300? Even in high gear hill pulling where the Allison automatic was no advantage, those trucks would pull with Cummins and other 350s with similar loads. We also had some Volvo/Whites with the supposedly equal 300 HP L10 Cummins, and the 300 Macks would run away from them.

I agree Teamstergrrrl!! Over in Lancaster NH was a Mack dealer (still is I guess). One of the "ole boys" who worked there (an absolute wizard when it came to Macks) always claimed the HP was always rated at the rear wheels. I still agree. I could gross 89,000 to 90,000 with helmock for Glens Falls NY. Those of us who hauled there had several different brands of trucks. Macks, two KW's and 2 Autocars. My Mack had a 300+ with a Fuller 13 over. It had been custom ordered by another logger for heavy duty work. Steel double frame, 44 camelback rears and a 20 front. I pulled an old HEAVY BWS 9 tier solid floor trailer with it. Tare weight was close to 39,000!! Climbing Mendon Mountain loaded side by each with either of the KW's, they both had 350 Cummins with Fullers also. I could outpull both going up the hill but they sure could outdo me going down the other side. They had Jakes and I had a Dynatard. Ya I know, with Dynatards you could do more dragging your feet on the road than the Dynatard did, except make noise. I've driven several other trucks in my days but the R686ST always held a special spot in my heart. I miss my truck a lot and wished I still had it, but the GOOD thing is, it's still going strong almost daily and I get to see it usually once a week if not more. It also now has a companion. He kept saying my old "Log Dog" was lonely so he bought a "Dirt Dog" to keep it company! It's a "well broken in" Superliner dump! Photos of my old one and his new one are attached!

Dave