teched Posted November 2, 2021 Share Posted November 2, 2021 Hello everyone, Hope you got your junk put away...the white stuff is a comin here in the Northeast. I had a guy stop in the shop last week and informed me that he has a 1958ish B Model with a diesel and triplex sitting in the weeds. Frame was cut at the front spring shackle and the outer fenders were gone but the rest was there. I have not seen it in person yet, but the price sounded real good. Soooo. I want to know what you think about a triplex behind a 6v53 Dripoit. Is it even possible to bolt it up. The Detroit is a SAE2 and I have no idea what the Triplex is...PS. Don't be haten 1 Quote Link to comment https://www.bigmacktrucks.com/topic/68637-found-another-mack-in-the-weeds/ Share on other sites More sharing options...
General Ike Posted November 2, 2021 Share Posted November 2, 2021 I've got a 6V53T in my B85F. Allison automatic behind it however. Fantastic motor as a replacement for this sized rig. Pretty sure the triplex is a single countershaft transmission. Not sure it would handle the torque of the 6v53. I mean I think you'd be fine with it as a hobby truck, but pulling a hill with any sort of load I think would be a risk. Upside though is much of the issues mating a triplex to a more modern engine (ie. 237) may be mitigated by the fact that the detroit is a high revving engine and the issues with the triplex is usually making sure you don't lug it at lower RPMS. I could be wrong, just what I think I remember reading in the past and from limited experience. Quote Ed Smith1957 B85F 1242 "The General Ike" Link to comment https://www.bigmacktrucks.com/topic/68637-found-another-mack-in-the-weeds/#findComment-482308 Share on other sites More sharing options...
teched Posted November 2, 2021 Author Share Posted November 2, 2021 I have got the engine install pretty well figured out and have been toying with the idea of what trans to use. I have the original Fuller 5 speed that came off the Detroit and I have the little Duplex from the 401 Gas job. I would love to keep 2 sticks but the Duplex would not enjoy the torque of the 6v53N. Being the Triplex if from a diesel i thought it would be better suited for the Detroit...If I can make it fit. According the build sheet it looks like its got a 6.20 rear axle and with 48" tire, 2500rpms and 1:1 in the transmission. It should run 52mph. If I push the Detroit to 2800 it should run about 57mph. Quote Link to comment https://www.bigmacktrucks.com/topic/68637-found-another-mack-in-the-weeds/#findComment-482310 Share on other sites More sharing options...
doubleclutchinweasel Posted November 2, 2021 Share Posted November 2, 2021 (edited) What kind of torque is that Detroit rated at? I see info suggesting 650-666. I think the n-plex boxes were used with engines rated up to 650 ft-lbs or so. If that's the case, it should be fine. Like with a Maxi, maybe keep the revs up...which shouldn't be an issue with the DD. Edited November 2, 2021 by doubleclutchinweasel Quote "Eagles may soar, but weasels don't get sucked into jet engines." Link to comment https://www.bigmacktrucks.com/topic/68637-found-another-mack-in-the-weeds/#findComment-482313 Share on other sites More sharing options...
teched Posted November 2, 2021 Author Share Posted November 2, 2021 About 200hp and 450ftlb torque Quote Link to comment https://www.bigmacktrucks.com/topic/68637-found-another-mack-in-the-weeds/#findComment-482314 Share on other sites More sharing options...
doubleclutchinweasel Posted November 2, 2021 Share Posted November 2, 2021 Certain models of Triplexes and Quadruplexes (and there ARE different models...check your model number) were routinely used behind the ENDT-673C, which was rated at 250HP and 701 ft-lbs of torque. I have hauled 111,000# with that setup many, many times. So... 1 Quote "Eagles may soar, but weasels don't get sucked into jet engines." Link to comment https://www.bigmacktrucks.com/topic/68637-found-another-mack-in-the-weeds/#findComment-482315 Share on other sites More sharing options...
doubleclutchinweasel Posted November 2, 2021 Share Posted November 2, 2021 Here was that engine... http://www.tyldenheritage.com.au/uploads/9/3/0/6/9306704/endt673c.pdf 1 Quote "Eagles may soar, but weasels don't get sucked into jet engines." Link to comment https://www.bigmacktrucks.com/topic/68637-found-another-mack-in-the-weeds/#findComment-482316 Share on other sites More sharing options...
teched Posted November 2, 2021 Author Share Posted November 2, 2021 Sounds like it will hold up, I'm not planning on using it hard. I have a time scheduled with the guy tomorrow evening to check it out. Quote Link to comment https://www.bigmacktrucks.com/topic/68637-found-another-mack-in-the-weeds/#findComment-482317 Share on other sites More sharing options...
doubleclutchinweasel Posted November 2, 2021 Share Posted November 2, 2021 I'm kind of a Quad-freak! I grew up on the 18-speed double-overdrive Quadruplex. Have driven the 13-speed Triplex version. Same, without the LO-LO gears. Love those 2 boxes. Once you learn them, there truly is a gear for all occasions. Had 2-3 different shifting sequences, depending on the load and grade. Even developed a couple of different split-shifting styles. Again, depended on how big of a hurry you were in. To me, a Mack needs 2 sticks. The 15 RoadRanger I had in my '70 was a much more user-friendly box. But, I always felt a little bad that it didn't have the Quad in it. I hope to have another one someday. 1 Quote "Eagles may soar, but weasels don't get sucked into jet engines." Link to comment https://www.bigmacktrucks.com/topic/68637-found-another-mack-in-the-weeds/#findComment-482319 Share on other sites More sharing options...
Draggin Wagon Posted November 3, 2021 Share Posted November 3, 2021 Put the 2 stroke in there!! It's your truck, don't even concern yourself with what anybody thinks. The small duplex is probably a 67 series and it might not like the ride too well. The triplex will be either single over or double over which will help road speed. GO for it and keep us posted 1 Quote Link to comment https://www.bigmacktrucks.com/topic/68637-found-another-mack-in-the-weeds/#findComment-482336 Share on other sites More sharing options...
mowerman Posted November 3, 2021 Share Posted November 3, 2021 Wow definitely got my attention like the guys said recreational use don’t even worry about it good luck… bob Quote Link to comment https://www.bigmacktrucks.com/topic/68637-found-another-mack-in-the-weeds/#findComment-482342 Share on other sites More sharing options...
teched Posted November 3, 2021 Author Share Posted November 3, 2021 It is for recreational use...maybe haul a trailer occasionally. I have to figure out the input shaft length and pilot bearing diameter... Quote Link to comment https://www.bigmacktrucks.com/topic/68637-found-another-mack-in-the-weeds/#findComment-482353 Share on other sites More sharing options...
doubleclutchinweasel Posted November 3, 2021 Share Posted November 3, 2021 Yeah, a TRT-7220 or TRQ-7220 should hold up fine. Learn to split all the gears, and that DD would sound great going up through the cogs! Only about 300 RPM drop if you hit all of them. Quote "Eagles may soar, but weasels don't get sucked into jet engines." Link to comment https://www.bigmacktrucks.com/topic/68637-found-another-mack-in-the-weeds/#findComment-482356 Share on other sites More sharing options...
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