Burmy Posted June 28, 2022 Author Share Posted June 28, 2022 On 6/25/2022 at 9:28 PM, mowerman said: Man that’s a pretty good price … Bob It looks like that truck has 56K rears. No leaf springs 1 Quote Link to comment https://www.bigmacktrucks.com/topic/69988-1986-mack-dm-685s-restoration-help/page/3/#findComment-501504 Share on other sites More sharing options...
mrsmackpaul Posted June 28, 2022 Share Posted June 28, 2022 On 6/28/2022 at 4:17 AM, Burmy said: I wish I woulda found that truck first ha! If that has a 300 motor, is it a ENDT or a E6. Don't ENDT's only go up to 285hp from factory? I would want to change the tranny on that truck and get rid of the front pizza cutter steers, those tires will sink on most of my jobsites! All of these motots you mention are E6 motors 285 is a coolpowered Maxidyne 2 valve 300 is a Maxidyne none coolpowered with the intercooler In front of the radiator and was a 4 valve 350 is a Thermodyne none coolpowered with the intercooler in front of the radiator and was a 4 valve 300 can also be a Thermodyne coolpowered motor that is a 2 valve or maybe a 4 valve depending on the era Can also have a 350 coolpower that is series cooled with 2 valveheads There is quite a long list of options, I have only scratched the surface here The coolpowered motor was a game changer in the industry for many years and really set Mack up as the leaders for a long time It is important to understand the differences when shopping for a truck as the sales man will always quote the higher value on power when selling a secong hand truck Even if you have a really good understanding I doubt anyone can tell what the pump is set to by looking Paul Quote Link to comment https://www.bigmacktrucks.com/topic/69988-1986-mack-dm-685s-restoration-help/page/3/#findComment-501518 Share on other sites More sharing options...
mowerman Posted July 2, 2022 Share Posted July 2, 2022 (BURMY),,,,i have grown to figure out ,,,you are very fussy..lol.bob Quote Link to comment https://www.bigmacktrucks.com/topic/69988-1986-mack-dm-685s-restoration-help/page/3/#findComment-501900 Share on other sites More sharing options...
Burmy Posted July 10, 2022 Author Share Posted July 10, 2022 On 6/28/2022 at 4:00 PM, mrsmackpaul said: All of these motots you mention are E6 motors 285 is a coolpowered Maxidyne 2 valve 300 is a Maxidyne none coolpowered with the intercooler In front of the radiator and was a 4 valve 350 is a Thermodyne none coolpowered with the intercooler in front of the radiator and was a 4 valve 300 can also be a Thermodyne coolpowered motor that is a 2 valve or maybe a 4 valve depending on the era Can also have a 350 coolpower that is series cooled with 2 valveheads There is quite a long list of options, I have only scratched the surface here The coolpowered motor was a game changer in the industry for many years and really set Mack up as the leaders for a long time It is important to understand the differences when shopping for a truck as the sales man will always quote the higher value on power when selling a secong hand truck Even if you have a really good understanding I doubt anyone can tell what the pump is set to by looking Paul Yes I did know the motor was considered an E6. Thank you for the info on all the other rated HP motors. I am slowly learning more about Mack trucks then intended haha! Quote Link to comment https://www.bigmacktrucks.com/topic/69988-1986-mack-dm-685s-restoration-help/page/3/#findComment-502666 Share on other sites More sharing options...
mowerman Posted July 10, 2022 Share Posted July 10, 2022 I didn’t think they E6 come out till way after 237 was popular I am not an authority on the engine codes bob 1 Quote Link to comment https://www.bigmacktrucks.com/topic/69988-1986-mack-dm-685s-restoration-help/page/3/#findComment-502681 Share on other sites More sharing options...
mowerman Posted July 10, 2022 Share Posted July 10, 2022 Quote Link to comment https://www.bigmacktrucks.com/topic/69988-1986-mack-dm-685s-restoration-help/page/3/#findComment-502703 Share on other sites More sharing options...
mowerman Posted July 10, 2022 Share Posted July 10, 2022 I found this in a very old post hope this helps . Bob Quote Link to comment https://www.bigmacktrucks.com/topic/69988-1986-mack-dm-685s-restoration-help/page/3/#findComment-502705 Share on other sites More sharing options...
mowerman Posted July 10, 2022 Share Posted July 10, 2022 Wow if you could add another 50 HP you would be in like flint Quote Link to comment https://www.bigmacktrucks.com/topic/69988-1986-mack-dm-685s-restoration-help/page/3/#findComment-502706 Share on other sites More sharing options...
Elephant ears Posted August 12, 2023 Share Posted August 12, 2023 On 6/21/2022 at 11:49 AM, Burmy said: A couple weeks ago I purchased a 1986 Mack DM 685S for 10K from Manders in Lakeville. The truck has a 13 speed tranny, and an ENDT 675 motor (235hp). I was told by Manders it had 285hp which would be the ENDT 676. After getting the truck home and power washing the motor block off I discovered it was the 235HP motor (not to happy about it) at the time I did not know to look for the aftercooler and twin pipes to the intake or that DM685 stood for the 235hp motor and DM686 stood for the 285HP motor, I DO NOW THOUGH! I was just going off what the salesman's was telling me! This DM will be replacing our current 1994 RD690s which has 300 HP. The original plan for the DM with "285hp" thought I was getting was to add a bigger fuel pump and make it have 350HP so more then the current RD and then restore the old DM. The DM at least needs 285HP as it will be pulling a 200 series hoe from jobsite to jobsite until we get a lowboy setup. So my questions are now... 1. Can the ENDT 675 handle 350Hp? 2. Where do I find a stock or aftermarket aftercooler? 3. Where do I find a twin tubed cold air intake? 4. Is this motor a 2 valve or 4 valve? which is considered better? 5. Should I sell this truck and try to find a DM686 with ENDT 676 motor? 6. is this the Ecodyne or Maxidyne motor? Which is considered better? 7. How would a ENDT 675 Pair with a 18 speed tranny? over kill is fine 😜 ***Any other thoughts, ideas or concerns are welcomed and thank you for your time and knowledge!*** Other plans for the truck paint it black, covert the bud rims to Hub piloted with Alco or ATX 24" rims. put in 4.17 rears or maybe go 3.94 rears or whatever Mack excepts after 4.17. air to pintle hitch. Hush mats and a better AC system (Any ideas???) remove the pusher axle (better off-road capabilities). Remove all old lights and convert to all LED. get rid of the 20" steering wheel for 16" or 18". Someday a smooth sided box for bigger logo placement with multi functional gate. Also toying with the idea of putting an 18 speed tranny in. I want the low end for hauling equipment and offroad but at least a truck that can do 75mph/ 80mph and not be revved out the entire time. Ultimately this is just a project truck for me, something old and cool to fix up that will be fun to drive, and will be put to work here and there as needed. Nice looking DM you can turn up that 237 to 300 if the engine is in good shape do not go to 350 HP and replace the gear box which is probably a 6spd mud stick with a Mack 12 spd very good trans low end off road grunt and higher highway speeds good luck 1 Quote Link to comment https://www.bigmacktrucks.com/topic/69988-1986-mack-dm-685s-restoration-help/page/3/#findComment-536826 Share on other sites More sharing options...
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