Allison MT643...

Intercity Coach, Motorhome and School Bus Rating ... since its out of a school bus.
Net input power 250 hp (186 kW)
Net input torque 640 lb-ft (868 N·m)
Vehicle weight Up to 42,000 lbs (19,051 kg) GVW or GCW

ENGINE INTERFACE
Acceptable full-load engine governed speed 2200-4000 rpm Non-Retarder model (MT643)
Minimum engine idle speed
(with transmission in drive) 500 rpm


MOUNTING
Engine SAE No. 2 ... has the adapter to cummins 5.9L 12V
MECHANICAL RATIOS (RANGE)* ... Not an overdrive trans but if i change to 3.54s will that matter?
First 3.58:1
Second 2.09:1
Third 1.39:1
Fourth 1.00:1
Reverse -5.67:1

CONTROL SYSTEM ... this means that it requires no computer and it uses a normal shifter correct?
Description Hydraulic
Driver-to-Transmission Interface Customer furnished cab-mounted shift selector

\/\/...Which of tese do i need to work in my truck?\/\/

SPEEDOMETER PROVISION (Only one may be specified)
Optional Speed Sensor Gear 16-tooth gear for magnetic pickup
Optional Mechanical Drive Gear 5-tooth helical drive gear for mechanical driven gear
Optional Mechanical Drive Gear 8-tooth helical drive gear for mechanical driven gear
Location Transmission rear cover

SIZE
Length* 31.9 in (809 mm)
Depth (below transmission centerline) 12.7 in (324 mm) Standard oil pan
12.0 in (305 mm) Optional shallow oil pan
Weight (dry without retarder) 510 lbs (231 kg)
Weight (dry with retarder) 555 lbs (251 kg)
*Length from engine housing to output flange face.

Anybody have this tranny? Anyone know the pros/cons of this tranny? What would need to be done to do a swap to this tranny into a 98 dodge 3500 12v auto?

I'm looking at buying this trans for $900 out of a 96 school bus. The tranny comes with the flywheel, flex plate, torque converter, bolts, AND engine flywheel housing removed from a 12V 5.9 Cummins.

Other option is spending what little money I have (under $2000) on my 47RE and hoping it holds up...

Thoughts?
All input is very welcome! need to make a decision on this quickly!

---AutoMerged DoublePost---

Also if this tranny is built for a vehicle that has a 42,000 GVW then would it be logical to say that in our 8,000 lb trucks it would stand up to a heck of a lot more abuse?

---AutoMerged DoublePost---

3 hrs on cummins forum i got more info and expertise than over 24 hrs on this site. Whats going on guys?