QU10021 OE NV4500 3rd-4th Gear Synchronizer Sleeves

QU10021 NV4500 3rd-4th Gear Synchronizer Sleeves fit all 1992-2007 GM and 1992-2005 Dodge New Venture NV4500 5 speed manual transmissions. If your original 3-4 sleeve has chewed up teeth or wear in the fork groove, it is time to replace it with a new one to restore smooth shifting performance. QU10021 is a New Old Stock (NOS) part. Made in USA.

No Longer Available. This part has superseded to QU10206

Need More Info? Use the handy Links below to access over 40 years of Dan's product and vehicle specific Tech Notes to easily get the information you need for your vehicle's repair, maintenance, or upgrade project!

Dan the Gear Man® Tech Notes:
Common Wear Issues
Synchronizer Assembly
NV4500 Tools
Lubricants, Sealants, Threadlockers
Matching Parts
Applications

Tech Note 1: Common Wear Issues
Synchro clutch teeth wear issues with NV4500 3-4 synchronizer sliding sleeves or rings is fairly common. In most cases, wear on the leading edge of the clutch teeth usually is caused by one or more of these causes: wrong or contaminated oil, clutch release issues, excessive transmission shaft end-play, shift fork wear, or use of bronze instead of lined synchro rings. A worn shift fork may also cause visible wear to the 3-4 slider shift fork groove.

Tech Note 2: Synchronizer Assembly
To make a complete 3-4 synchronizer assembly, order QU10206 sleeve + QU10122 Hub + QK1099 Synchro Strut Kit. 3-4 Synchro assembly procedures are covered in my TM1003 NV4500 Shop Manual or V1003DVD NV4500 Overhaul Video.

Tech Note 3: NV4500 Tools
Need Torque Specs or Rebuild procedures? Order my 116 page, full color illustrated TM1003 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.

Tech Note 4: Lubricants, Sealants, Threadlockers
Early production NV4500 Transmissions used an anaerobic sealant (QU90003) to seal between the main case and input bearing retainer, top cover, and rear housing. Mid-production units used anaerobic sealant just on the input retainer and RTV for everything else. Later production transmissions used black RTV Sealant (QU90006 or QU90005) for everything. Either type of sealant works fine (except the PTO covers ALWAYS should be sealed with RTV), but I prefer RTV for all components. Regardless of which sealant you use, make sure excess sealant does not block the lube access hole at the top of input retainer pilot that fits into the transmission case. Also, the threaded holes in the main case for the four retainer bolts and 12 PTO bolts are open ended, so you must use new bolts with factory applied threadlocker or apply Threadlocker (S24200) to your existing bolts to prevent oil seepage past the bolt threads. See my TM1003 NV4500 Shop Manual or V1003DVD NV4500 Overhaul Video for more information.

Lubricant and Chemical List for NV4500 Transmissions
QU90020 NV4500 Manual Transmission Oil
QU90003 Anaerobic Sealant
QU90006 3.35 oz Ultra Black RTV Sealant
QU90005 0.5 oz Ultra Black RTV Sealant
S24200 6ml Medium Strength Blue Threadlocker
S9978 1 gram Medium Strength Blue Threadlocker
S9979 1 gram High Strength Red Threadlocker
S24026 High Temperature Threadlocker for Mainshaft Nut

Tech Note 5: Matching Parts
Other Matching Parts for QU10021 3rd - 4th Gear Synchro Sleeves:
QU10122 3-4 Synchro Hub
QK1099 Synchro Strut Kit
QU10004 3-4 Synchronizer Friction Ring (uses 2)
QU10732 3-4 Synchronizer Assembly
QU10049 or QU10702 4th Gear Clutch
QU10099 28 Tooth Mainshaft 3rd Gear 1992-1994 GM
QU10201 29 Tooth Mainshaft 3rd Gear 1992-2005 Dodge, 1995-2007 GM
QU10032 or QU10082 3-4 Shift Fork

Applications:

Chevy and GMC:
1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999 C1500, K1500, C2500, K2500, C3500, C3500HD, K3500 with NV4500 5 Speed
2000, 2001, 2002, 2003, 2004, 2005, 2006 C2500, K2500, C3500, K3500 Standard and HD Pickup based models with NV4500 5 Speed
2000, 2001, 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, 1990, 1991, 1992, 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, 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003 Ram 2500, Ram 3500 with V10 and NV4500HD 5 Speed
1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004 Ram 2500, Ram 3500 with Cummins Diesel and NV4500HD 5 Speed
1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005 Ram 2500, Ram 3500 with gas V8 and NV4500LD 5 Speed