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03' Big Red

Porch Pup
  • Content Count

    64
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5 Good

About 03' Big Red

  • Rank
    Old Iron Expert
  • Birthday September 24

Profile Information

  • Gender
    Male
  • Location
    Pennsylvania

Previous Fields

  • Make
    Mack
  • Model
    RD688s
  • Year
    2003

Recent Profile Visitors

1,293 profile views
  1. 03' Big Red

    Allison automatic

    What axle ratio does your truck have ? Also does your trans have a rear support? I know the 4000 series requires one. i know that I need to pay close attention to tooth count on flex plate and tone ring/ speedometer gear to make things work.
  2. 03' Big Red

    Allison automatic

    I have a few questions about parts interchangeably, will a Allison 700 series bolt up to a 4000 series flywheel housing and flex plate? is a spacer needed ? If so what p/n ? also what is the tooth count on the 700 series speedometer? My Final question, will the output shaft yoke from a 4000 series fit a 700 series this is for a conversion project in a 03 Mack RD688s that currently runs a Eaton 8LL
  3. 03' Big Red

    Allison Automatics

    What was the axle ratio on your truck ?
  4. 03' Big Red

    Allison conversion

    Is that HT754CR going to hold up to a E9 ? I thought the torque rating was much lower than the 750DRD Am I correct the 1st gear ratio is 8.0 ? Or something like that on the 754 my truck has the AMI 370 and I would be pushing the torque limits. It’s around 1480 ftlb
  5. 03' Big Red

    Allison conversion

    Ok folks i am still working on the details of this swap, I have a vin From a 2000 rd with a Allison, can anyone tell me which Allison this unit has and 1st gear ratio and also the axle ratio ? Vin 054124 also talked to another Mack tech and he says all that’s needed for the engine computer is to change the top gear ratio and change it to A designation for the automatic.. i would appreciate any other input in this swap, I plan to use to 750DRD for simplicity I also need to know what bell housing,flexplate and mounts to use.
  6. 03' Big Red

    AMI 370 power increase

    Did I say 1300 rpm ? My bad, it’s more like 1500 rpm, I am still considering the manifold and turbo ..
  7. 03' Big Red

    AMI 370 power increase

    I have not as of yet, just hit the 90,000 ish mark on a in frame, the engine really loosened up and runs excellent, I can shift at 1300 rpm now and it has the power to keep pulling, until recently I had to rev to 1800 or so. This is a tri axle, the gross weight here in PA is 73280 lbs
  8. 03' Big Red

    Mack e7 350 vs ami 335

    The AMI has a much better rpm range 1200-2150 rpm and the torque rise is considerably more maybe 40-50% thats just a guess since I don’t recall exactly what it is... the AMI should out run the E7
  9. 03' Big Red

    Allison conversion

    I would really like to keep this truck since I know what I have and to find a RD with a automatic set up like I need is fairly difficult. i did find a 2003 RD on the internet with a Allison VIN # 1M2P296C23M066900 this should help me create a parts list if I can’t find a suitable donor truck, my guess sticking with a RD would be my best bet for a donor truck.
  10. 03' Big Red

    Allison conversion

    Thanks for the info, I did find a RD single axle that would work much better.
  11. 03' Big Red

    Allison conversion

    I talked to my local Mack dealer, they contacted Mack engineering who wouldn’t release any info. i did find several 2001 LE donor chassis with the 4500 series trans, would the mounts and such from the LE work in my RD ? i would appreciate any information in regard to what I may have to change in my ECM, and if any changes are needed can a competent shop make those changes? Or would I have to find a dealership that would make things happen?
  12. 03' Big Red

    Allison conversion

    I want to swap in a Allison 750DRD in my 2003 RD688S i run the Eaton 8LL now... no computer on trans my question is how will my ECM be effected ? amd what year donor chassis would work to get all the pieces needed? i am looking at a MR for the donor chassis
  13. 03' Big Red

    AMI 370 power increase

    So I am relatively new to this stuff, am I correct in saying that to go from a 370 to 460 its just a turbo and injector change and no ECM work ? Not that I want to change anything in my ECM, just curious. I’ve heard about a 460 XT that’s about 485 HP is that also injector and turbo or does it include ECM ? Sent from my iPhone using Tapatalk
  14. 03' Big Red

    AMI 370 power increase

    Any idea what kind of horsepower you have now ? Sent from my iPhone using Tapatalk
  15. 03' Big Red

    AMI 370 power increase

    That would be awesome! Sent from my iPhone using Tapatalk

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