DS4831-5521 DS PUMP

Description

Huckstorf Diesel Rebuilt Stanadyne DS4831-5521 Diesel Fuel Injection Pump for 1994-2002 Electronic GM 6.5L Trucks, Vans, & H1 Hummers

Due to parts obsolesce, we no longer offer a rebuilt exchange pump.  We do offer a repair service of your pump.  The Stanadyne parts needed to do a proper rebuild are not being produced any longer.  Alliant Power bought out the existing inventory from Stanadyne and the supply of PMD’s along with the Encoder Sensors have been used up.  Give us a call at 414-421-7222 to discuss pump repair options.  We can repair your pump using your encoder sensor and a Flight Systems PMD.  We are not aware of another encoder sensor option.

The following trouble codes refer  to bad encoder sensors;

• 1994-1995 Vehicles
  • 17 = High resolution circuit fault.
  • 18 = Pump cam reference pulse error.
• 1996-2001 Vehicles
  • P0251 = Injection pump cam system.
  • P0370 = Timing reference A high resolution.

Stanadyne 05221S  DS4831-5521

Huckstorf Diesel is an authorized Stanadyne dealer, and we have the ability to rebuild these pumps in house. We offer exchange injection pumps for the 1994-2002 6.5 turbocharged Chevy/GMC GM 6.5L  diesel engines. These electronically governed injection pumps are rebuilt using all the necessary parts to make the pump perform as good as, or better than new. Our technicians carefully inspect each part. All parts that don’t pass our strict criteria get replaced with original equipment Stanadyne parts. We do not install inferior, lower quality, less expensive parts. Each pump is carefully set to the high side of the Stanadyne specifications to give you the optimal performance.

If you prefer to have your fuel injection pump rebuilt instead of taking an exchange, we can certainly do that for you. With this option we can sometimes save you money if your pump is in better shape than the average and need to install fewer parts than the average.

We are seeing the effects of the high mileage being accumulated on these engines. We replace all the necessary parts needed to rebuild a used pump to new standards. Genuine Stanadyne parts are used unless they are no longer available from Stanadyne.

This pump is a direct replacement for the following pump numbers;

• DS4831-5942
• DS4831-5459
• DS4831-5521
• DS4831-5288
• DS4831-5067

In 1994 there were two pump versions produced.  This pump fits all applications except HD applications with VIN code F and pump tag number DS4031-5068.  This pump is not compatible with the 5068 pump.

This pump comes with a one year warranty. Restrictions do apply.

Core is required.

No Core Charge 

No core charge due to us only offering a repair service of your pump using your encoder sensor over again.

In 1992 General Motors replaced the 6.2L diesel engine with the 6.5L engine.  The engine was designed to be a more powerful version of the 6.2 and met emission standards required for half-ton trucks.  In 2001 the 6.5 was replaced by the 6.6L Duramax engine in light and medium trucks and starting in 2003 in vans.  The 6.5 is still being used in some AM General applications, mainly for the military.  The piston stroke was lengthened to achieve the extra cubic inches.  Machining the bore further into the block caused a lack of material between the main cap bolt holes and the cylinder walls.  The main bearing web in the block was prone to cracking.  That made these engines poor candidates for big performance upgrades.  The Duramax engine is much more capable of making power levels that matched or exceeded the Ford and Dodge diesel offerings.   Horsepower numbers for the 6.5L started at 180 HP @ 3400 rpm and peaked at 315 HP @ 3200 rpm.  Torque ranged from 360 lb-ft @ 1700 rpm to 530 lb-ft @ 1800 rpm.

There are several GM 6.5 liter diesel engine production options. The Turbocharged L56, (VIN “S”) was used in most light duty 3/4 ton (2500) Heavy duty 3/4 ton and 1 ton trucks used the Turbocharged L65 (VIN “F”) engine. The L56 is emissions controlled with EGR and catalytic converters. The L65 engine has no EGR, and has no catalytic converter. There is a soot trap on L65 engines that is often mistaken for a catalytic converter. The L49 (VIN “P”) and L57 are both naturally aspirated engines. L57 is listed as HO or Heavy Duty. Additional RPO codes are LQM (175HP) and LQN (190HP).

Changes were made by GM to the 6.5 in their light trucks for emissions or reliability improvement. The 1992-1993 model years used a 6.5-specific Stanadyne DB-2 mechanical injection pump. GM replaced the DB-2 with the electronic throttle DS-4 in 1994-2000 vehicles.  The DS style pump used a pump mounted driver known as the PMD.  The PMD is an electrical solenoid that drives a plunger solenoid inside the injection pump.  These PMD’s have had reliability issues that still persist after many revisions.   In mid-1996 GM implemented a redesigned engine cooling system incorporating twin non bypass-blocking thermostats and a 130 GPM water pump. This improved the flow through the block by 70-75% and flow to the radiator 7%.

Through the years there were many different variations in the 6.5 diesel injection pumps.  The engine application codes were based off the Truck Style, Model Designation, and if the engine was equipped with or without a turbocharger.

This pump will work on the following applications.  Due to minor differences this pump may not be a direct supersession, but will work properly.  If you want your pump built to a specific model code, Huckstorf Diesel will be happy to do that for you.  If you want to have your pump customized for a performance application we can do that also.  Give us a call and we can discuss your options!

GM 6.2 & 6.5 Diesel Engine Application Codes

Truck Styles

C, R = 2 Wheel Drive
K, V = 4 Wheel Drive
G = Van
P = Recreational Vehicle, Motor Home, Step Van
D, CUCV = Military (Commercial Utility Cargo Vehicle)
HMMWV = Military (High Mobility Multi Wheeled Vehicle)

Starting with the 1988 model year, the C/K designation was changed to the R/V designation with the body style change.

Model Designations

LD = Light Duty (with EGR)
HD = Heavy Duty
SD = Super Duty (6.5 – 15,000 GVW)
ALT = Altitude
CAL – California Only

Other Designations

N/A = Naturally Aspirated
Turbo = Turbo Charged
1.2 cSt = Low viscosity fuel compatible (Military)

GM Part Numbers

12561307S
19209059S

See the wide variety of 1982-2000 GM 6.2 & 6.5 diesel performance, repair, and maintenance parts offered by Huckstorf Diesel here, and in person at Wisconsin’s premier diesel repair, performance, and installation center located just outside of Milwaukee Wisconsin in Franklin WI.