The New Venture Gear NV3500
(85 mm) is a five speed manual transmission used on light duty truck with
  4.3L, 5.0L, and 5.7L engines. This manual transmission is identified by
the   RPO's M50 and MG5. The reason for 2 different RPO codes  is because
of  the  different first speed gear ratios that the transmission   can contain.
 The  shift assembly design inside the transmission  for NV3500 installed
on  C/K   (GMT400 and GMT 800) trucks are different from  that of  NV3500
 transmissions   that are installed in smaller S/T trucks. The  85 mm  is
the distance  between   the input shaft and the counter shaft. The transmission
is available  in rear   wheel and 4WD versions. The NV3500 transmission  
is built   in  Muncie, Indiana by New Venture Gear, (a division of New Process
Gear)  for   General Motors Powertrain.
The transmission has the following features:
|     •  | Constant mesh helical gearing for reduced noise | 
 
|     •  | A 2 piece aluminum housing | 
 
|     •  | Synchronized shifting in all forward gears | 
 
|     •  | A shift tower mounted shift lever | 
 
|     •  | Single rail shift system | 
 
                        
The New Venture Gear NV 3500  is a 5 speed  manual transmission
   used on light duty trucks with the 4.3L  engine. The  NV 3500 is
 identified   by RPO M50 and RPO MG5. The difference  between
 the RPO codes    is the first speed gear  ratios that the transmission  has.
 The shift assembly   design inside  the NV 3500 transmission  installed
 on C/K trucks   is different than the NV 3500 transmissions
  installed in smaller  S/T trucks.  The distance between  the input
 shaft and the countershaft  is 85 mm  (0.132 in). The transmission
  is available in rear   wheel drive and  four wheel drive.
The transmission has the following features:
|     •  | Constant mesh helical gearing for reduced noise | 
 
|     •  | A 2 piece aluminum housing | 
 
|     •  | Synchronized shifting in all gears | 
 
|     •  | A shift tower mounted shift lever | 
 
|     •  | A single rail shift system | 
 
|     •  | A vehicle speed sensor (VSS) |