QU10075 39 Tooth NV4500 Mainshaft 1st Gear


QU10075 NV4500 39 Tooth Mainshaft 1st Gear These new takeout gears are genuine New Venture 1st gears from brand new transmissions we disassembled for parts. QU10075 fits all 1992-2007 New Venture NV4500 transmission models. This big, rugged gear rarely needs replacement. When it does, the problem is usually caused by running the wrong or contaminated oil which will result in synchro clutch tooth wear and/or bearing failure. Made in U.S.A.

Genuine NVG 39 Tooth 1st Gear
* Kits made up of multiple items may not show an inventory in-stock status but are almost always in stock!

tech note

Dan the Gear Man® Tech Note 1:
QU10075 is a 39 tooth, bearing supported mainshaft 1st gear that is compatible with ALL New Venture NV4500 5 speed manual transmissions regardless of 1st gear reduction ratio. All NV4500 countershafts have 12 1st gear teeth so QU10075 works in both medium ratio NV4500 transmissions with 5.61:1 1st gear ratio AND wide ratio 1992-1994 GM NV4500 models with the 6.34:1 1st gear ratio.

tech note

Dan the Gear Man® Tech Note 2:
1st Gear failures in New Venture NV4500 5 speed manual transmissions are usually a lubrication related failure that damages the bearing bore. Another failure is synchronizer clutch tooth wear and or synchro cone wear caused by incorrect lubricant or the use of cheap imported bronze synchro rings instead of OE style lined steel rings. Problems with your clutch not fully releasing or crankshaft pilot bearing/bushing dragging can also lead to clutch teeth wear from "grinding" the gears during shifting.

NV4500 mainshaft 1st Gear tooth breakage is usually limited to mega-horsepower competition vehicles.  There are claims that cryogenically treating NV4500 gears will increase gear strength as much as 30%. Unfortunately, there does not seem to be any peer-reviewed documentary evidence to support those claims. Cryogenically treating gears is primarily a cold-hardening process that changes the molecular structure of steel to decrease wear while retaining or increasing hardness. If properly done, it is probable the cryogenic treatment process does slightly increase the impact and fatigue resistance of NV4500 gears, but not enough to significantly increase the ability of an NV4500 transmission to reliably handle more than 600 Lb.-Ft. of input torque especially considering the maximum factory torque rating of the  NV4500HD transmission is only 460 Lb.-Ft..

tech note

Dan the Gear Man® Tech Note 3:
Need Torque Specs or Rebuild procedures? Order my 116 page, full color illustrated NV4500 Rebuild Manual.

You will need some special tools to correctly service your NV4500 Transmission. The chart below lists our current NV4500 Special Tools for popular models.


Component 23 Spline
Dodge 4x4
29 Spline
Dodge 4x4
30 Spline
Dodge 4x2
31 Spline
Dodge 4x2
32 Spline
GM 4x4
35 Spline
GM 4x2
Mainshaft Nut QT2002 QT2001
QT2002 QT2001
1-1/2" Hex
Mainshaft Holding NLA QT2000 NLA QT2011 N/A N/A
5th Gear Nut
Torx® Cross Bolt
N/A QT9205 N/A QT9205 N/A N/A
Output Seal Installer N/A QT1801 N/A QT2058
Not Used Not Used
Tailshaft Bushing Remover and Installer Not Used Not Used Not Used QT2044 Not Used Not Used


Front Bearing Cup Installer
QT1802 Use with QT1101 or QT1119 Driver Handle. Also can use flat side to install Dodge 4x4 Rear Output Seal
Countershaft Front Bearing Installer QT2004 Can also use to press 3-4 Synchro Hub on original equipment mainshafts
Input Bearing & Countershaft Rear Bearing Installer QT2005 Can also use to install Input Seal
Input Bearing Cup Installer QT1801 Use with QT1100, QT1101, QT1116, or QT1119 Driver Handle.
Countershaft Support QT2006 Use to support front of countersahft when installing countershaft rear bearing
1-2 Synchronizer Support QT2008 Use to support 1-2 synchronizer hub during synchronizer assembly
10mm 1/2" Drive 12 Point Socket QT1020 USA Made Impact Socket for Factory Tailshaft Housing Bolts
Long Shank Punch for Shift Lug QT9300 3/16" x 8" Shank for 5th Gear Shift Lug Roll Pin
tech note

Dan the Gear Man® Tech Note 4:
Matching Countershaft Part Numbers for QU10075 1st Gear are:

Application Countershaft Type 1st Gear Ratio
1992-1994 Dodge
1992-1994 GM
QU10090 Modular
1992-1994 Optional for Dodge  QU10078 One Piece 5.61
1995-1996 Dodge
1995-1996 GM
QU10078 One Piece 5.61
1997-2005 Dodge
1997-2007 GM
One Piece 5.61
tech note

Dan the Gear Man® Tech Note 5:
Matching Popular Mainshaft Part Numbers for QU10075 1st Gear are:

Application Mainshaft Engine Output Spline
1992-1993 Dodge 4x4
1994-2005 Dodge NV4500LD
QU10214 Gas V8 23
1994-2004 Dodge 4x4 NV4500HD  QA1045
Diesel or V10 29
1995-2004 Dodge 4x2 NV4500HD QU10013 Diesel or V10 31
1992-2007 GM 4x4 QU10098 All 32
1997-2007 GM C-Series 4x2 QU10719 All 35
tech note

Dan the Gear Man® Tech Note 6:
NV4500 Transmissions have 3 1st Gear Synchronizer Rings. Matching Synchronizer Parts for QU10075 Gear are:

Gear  Synchronizer
QK1058 Not Available QU10081 QK1100 QU10002**
QU10215* Not Available QU10081 QK1100 QU10002**
1994-1995 Dodge QK1058 QU10038 QU10081 QK1100 QU10002**
1996-2007 All QK1058 QU10038 QU10081 QK1100 QU10002**

 *QU10215 1-2 Synchronizer Assembly with Shift Interlock can be replaced by QK1058 if desired. The Shift Interlock was intended to prevent down-shifting at high speeds.

**QU10002 is the Center Friction Ring. QU10014 is the Inner Steel Ring. QU10015 is the Outer Steel Ring.

tech note

Dan the Gear Man® Tech Note 7:
Other Matching Parts for QU10075 1st Gear:
QU10055 Bearing, 1st Gear
QU10002 Synchronizer Ring, Center Friction
QU10014 Synchronizer Ring, Inner Steel
QU10015 Synchronizer Ring, Outer Steel
QU10001 Premium Bearing and Seal Kit 1992-1996 Dodge
QU10005 Premium Bearing and Seal Kit 1997-2005 Dodge
QU10061 Premium Bearing and Seal Kit 1992-1995 GM 4x4
QU10062 Premium Bearing and Seal Kit 1996-2005 GM 4x4
QU10063 Premium Bearing and Seal Kit 1992-1995 GM 4x2
QU10064 Premium Bearing and Seal Kit 1996-2007 GM 4x2
QU90020 NV4500 Manual Transmission Oil
TM1003 NV4500 Shop Manual
V1003DVD NV4500 Overhaul Video


Chevy and GMC:
1992-1999 C1500, K1500, C2500, K2500, C3500, C3500HD, K3500 with NV4500 5 Speed
2000-2006 C2500, K2500, C3500, K3500 Standard and HD Pickup based models with NV4500 5 Speed
2000-2002 C3500HD 15,000 Lb. GCVW Cab and Chassis with NV4500 5 Speed
2007 C2500, K2500 Silverado Classic and Sierra Classic with NV4500 5 Speed

Dodge and Ram:
1989-1993 D250, W250, D350, W350 with Cummins Diesel AND our NV4500 Transmission Retrofit Kit
1992-1993 Ramcharger, D150, W150 with NV4500 5 Speed
1992-1993 D250, W250, D350, W350 with Gas Engine and NV4500 5 Speed
1994-2003 Ram 2500, Ram 3500 with V10 and NV4500HD 5 Speed
1997-2004 Ram 2500, Ram 3500 with Cummins Diesel and NV4500HD 5 Speed
1997-2005 Ram 2500, Ram 3500 with gas V8 and NV4500LD 5 Speed