Tate Posted September 22, 2022 Share Posted September 22, 2022 I have a 99 RD688S with a 400 E7 that I’ve done some work on. Have gone to a 400 series turbo ( none waste gate) stage 2 nozzles, polished manifold and k&n air filter. Truck pulls good bit in a hard pull in 7th gear it hits the wall at 1850 rpm’s. She won’t spin over that. Put new EUP’s and lift pump on still the same. My Mack dealer which is 2.5 hours away can’t help me out because I’m looking for the 460xt program. My local mechanic has the laptop and cable to hook up for remote tuning but his guy doesn’t do anything that old. Can anyone here help me out? 1 Quote Link to comment Share on other sites More sharing options...
Joey Mack Posted September 22, 2022 Share Posted September 22, 2022 is there a torque limiting switch and/or a setting in the EECU? 1 Quote Link to comment Share on other sites More sharing options...
Tate Posted September 22, 2022 Author Share Posted September 22, 2022 (edited) 28 minutes ago, Joey Mack said: is there a torque limiting switch and/or a setting in the EECU? Where abouts would I find the switch? I’d need to have a Mack computer to check the setting ? When empty it’ll spin up to 2150 easily and in 1st through 5th gear when loaded. It’ll go about to 2000 rpm’s in 6th but I never shift that high. Just notice it when in 7th gear. It’s a 8 double L trany Edited September 22, 2022 by Tate Quote Link to comment Share on other sites More sharing options...
Joey Mack Posted September 22, 2022 Share Posted September 22, 2022 on top of the transmission...on the shift cover... Im sorry that i cant just pull it out of my a$$.. jojo Quote Link to comment Share on other sites More sharing options...
Joey Mack Posted September 22, 2022 Share Posted September 22, 2022 I'm sorry if I steer you wrong,, i am trying to pull this out of my ass.. Your truck is old enough where there should be an easier solution, unlike the shit we see after 2003+.... jojo Quote Link to comment Share on other sites More sharing options...
880joe Posted September 23, 2022 Share Posted September 23, 2022 Good luck finding a remote tuner I've run etechs for 20 years and haven't found 1 yet. There used to be a place named Illinois Diesel I believe that could do tuning if you sent them your ECM don't know if their still around or not 1 Quote Link to comment Share on other sites More sharing options...
Popular Post Dirtymilkman Posted September 23, 2022 Popular Post Share Posted September 23, 2022 Why would you want to run over 1800 rpms? You're out of your power band at that rpm. 3 1 Quote Link to comment Share on other sites More sharing options...
fjh Posted September 23, 2022 Share Posted September 23, 2022 16 hours ago, Tate said: I have a 99 RD688S with a 400 E7 that I’ve done some work on. Have gone to a 400 series turbo ( none waste gate) stage 2 nozzles, polished manifold and k&n air filter. Truck pulls good bit in a hard pull in 7th gear it hits the wall at 1850 rpm’s. She won’t spin over that. Put new EUP’s and lift pump on still the same. My Mack dealer which is 2.5 hours away can’t help me out because I’m looking for the 460xt program. My local mechanic has the laptop and cable to hook up for remote tuning but his guy doesn’t do anything that old. Can anyone here help me out? I doubt Mack will not let you have the Xt program not enough cooling will be the excuse or a non Mack drive line will be another excuse! 1 Quote Link to comment Share on other sites More sharing options...
Joey Mack Posted September 23, 2022 Share Posted September 23, 2022 yep, typically, you have to have a 13 or 18 spd. tranny, and 200 series carriers... if it is a Mack drive line. The 400 is a great setup. I drove a few of them in a construction environment, 22 years ago, and that RD tractor had an 18 speed tranny, and it would out pull the newer (at the time) 427's.. Maybe set the governor setting to all speed to improve throttle response... jojo Quote Link to comment Share on other sites More sharing options...
Mackpro Posted September 24, 2022 Share Posted September 24, 2022 (edited) Most all ETECH’s will only turn 1950 in the last/top gear. However 2100 or 2150 ( I can’t remember) in all the lower gears is normal. I think the ASET AI with AMI engine data files ( AMI 370 for example) would go higher in the last gear. There might have been a few other specialty data files that would go higher as well. Edited September 24, 2022 by Mackpro 1 Quote Link to comment Share on other sites More sharing options...
Mackpro Posted September 24, 2022 Share Posted September 24, 2022 On 9/23/2022 at 10:05 AM, fjh said: I doubt Mack will not let you have the Xt program not enough cooling will be the excuse or a non Mack drive line will be another excuse! The good thing about VMAC 3 ECM Programing ( ETECH, CCRS and ASET) is there are ways around asking corporate for permission for HP upgrades. With dealer access you can program as many ETECH engine ECM’s as you want with the XT file. Now finding a dealership that knows how to do it and that will do it is the problem. 1 Quote Link to comment Share on other sites More sharing options...
fjh Posted September 25, 2022 Share Posted September 25, 2022 22 hours ago, Mackpro said: The good thing about VMAC 3 ECM Programing ( ETECH, CCRS and ASET) is there are ways around asking corporate for permission for HP upgrades. With dealer access you can program as many ETECH engine ECM’s as you want with the XT file. Now finding a dealership that knows how to do it and that will do it is the problem. Ahh good to know! Quote Link to comment Share on other sites More sharing options...
DieselDog5.9 Posted September 25, 2022 Share Posted September 25, 2022 There are numerous paramaters in the program that can be turned on or off. One of those is road speed, if the road speed is limited to 63mph, you are not going to pull full rpms out of the engine in top gear. I went to the mack garage and they turned off the torque limiting when on the low side of the transmission, and the speed limit of 63mph. The worst part of that 400 is the rpm range, it falls on its face at 1500rpm, but mine is a 2003 so maybe it is different. But I found a cure for that also. Quote Link to comment Share on other sites More sharing options...
Joey Mack Posted September 25, 2022 Share Posted September 25, 2022 If I remember right, you can set the gov. to 'all speed' and you can set pedal spd. and cruise spd. to about 75 mph.. as far as 400 RPM range. I guess because i was driving an 18 spd.. I set the range... I wish I was still driving today, in the trucks that are being fussed at.. I feel like I will learn something.. Back in my driving time, it was about getting the dirt to the job site. anyway,,, I know less and less everyday... Quote Link to comment Share on other sites More sharing options...
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