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About jkruss82

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    Over Drive

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    Central PA
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    Engineer for the best truck in the world

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  1. jkruss82

    Allison conversion

    Pretty big undertaking. Special transmission wire harness, and engine wire harnesses needed. Does the donor chassis have the same engine type as your RD, then maybe you could just pull the donor ECM. Not sure about component shop flashing new software. Flywheel housing should be the same, but flywheel needs swapped out and you need the spacer ring. Allisons are very heavy and require rear buggy spring mounts at the rear of the transmission, so you probably need to fabricate brackets on your frame. I'm not familiar with where the RD rear engine mounts are located (Flywheel Housing or Side of transmission) in either case they will not likely be the same. There would probably be more headaches along the way, that I'm not thinking of. Hate to say this, but I'd recommend trading your truck to get the transmission you want. Pic of buggy spring
  2. jkruss82

    MP 8 ?

    Its a 425HP engine. 338 may be the hp at 2100 RPM, but max hp is around 1600-1700 RPM.
  3. jkruss82

    Mack tm308m transmission

    Forward 6+2 1 2 3 4 5 6 7 8 17.77 10.94 6.57 4.05 2.54 1.57 1.00 0.71 Reverse 15.59 9.60 6.02 3.73 2.37 1.69
  4. jkruss82

    TC15/TC25 transfer case

    You can probably make this work as long as you pay close attention to plumbing the correct air and oil lines. You will also need to be careful with driveshaft angles, since the input and output shafts have a pretty large offset. Also there were lots of different HI and LO ratios available on these units. for example TC15 LO-2.59 HI-1.00 and TC25 LO-2.59 HI-1.36 Good luck if you try this.
  5. jkruss82

    Tranny hi low issue

    Recommend checking air pressure on both sides of the shift cylinder and shift between Hi and Lo, and do this with a warm transmission if possible. Its possibly you just need some seals I've generally heard that the shifting gets better on a warm trans, but in your case the opposite could possibly be true.
  6. jkruss82

    18 speed gear split problems

    If its the splitter, its the top cover on the back box that possibly needs to have the air cylinder rebuilt (new o-rings, maybe new brass air fittings) and check the air lines and other fittings on top of the transmission.
  7. jkruss82

    Maxitorque ES wide range of models and speeds

    Unfortunately Australia tightened up their noise regulations and Mack dropped their manuals from being offered about 6 years ago. I think you may be able to special request one, but I would hate to know the cost. In the USA Mack sells mDrive, Allison, Eaton, and Mack T300. About 20% of trucks still have a stick, the other 80% do not and that number continues to grow.
  8. jkruss82

    Maxitorque ES wide range of models and speeds

    The Mack 6 speed is gone from production. It was nice and lightweight for a class 8 truck, but drive-ability and reliability not so great. Mack's manual transmission take rate is about 10% of new trucks. Mack has the most PTO options available and a 10 speeed multi-speed reverse (T310M) that is shiftable through 6 reverse gears. Otherwise Mack and Eaton match up pretty close with 9/10/13/18 speeds.
  9. jkruss82

    T2080 input shaft

    it may be for flywheel PTO New Picture.bmp
  10. jkruss82

    13 speed won't go to low range

    Sounds like it may need new seals and o-rings if the air lines are all still connected properly.
  11. jkruss82

    Eaton conversion

    Whats wrong with the Mack 13spd if you don't mind me asking? For the Eaton you can use either aluminum or cast iron bell housing with the correct clutch release. You will probably need a longer prop shaft as well.
  12. jkruss82

    Change pto bar Mack MR

    Do you mean shaft? Dig those swivel clips out with a flathead screwdriver and punch the pin through.
  13. jkruss82

    Transmission swap

    The pilot bearing floats in the flywheel, nothing holds the new ones without snap rings. Good idea to replace the pilot bearing, they tend to go bad from the clutch dust and such.
  14. jkruss82

    T310 knocking!

    Is this a new transmission or does it have a many miles? Sometimes a gear will have a bad spot and sound like a knocking during coast. If you have a T310 and its in low speed, the gear set directly behind the mainbox (in the rear box) is most likely the culprit of the knocking noise. That being said this noise may go away after the bad spot gets worn down, but that's only if this is a new or Reman new transmission.

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