Flash Off-Road Chevy - GM - Hummer PMD Cooler Kit



Customers Include the US Navy, Army and National Forest Service


FSD Cooler

6.5 Diesel PMD Cooler Kit made in the USA

Note that a PMD and an FSD are the same thing.

This kit works great on Hummers and all GM 6.5 turbo diesel engines. The Master kit includes everything you need to get your truck running again. Included is a GM, OEM PMD, #9 resistor, heat sink a 6' Extension Cable and all necessary hardware including heat sink compound and cable seal. The cable is one of the most important parts of the kit because it allows you to mount the PMD away from the hot engine.

Other companies claim that mounting the PMD on top of the engine is cooler than mounting it away from the engine. That's because their kit price will be higher if they have to include the 6' cable.

Unlike other kits This Kit Comes with a 6 Foot Extension Cable


Note: If you have a newer style (grey colored) Stanadyne PMD let us know because it uses a different cable.


The buttons below will allow you to pay with Visa, Mastercard, Discover and Paypal

The Prices Include Shipping by USPS Priority mail which is 2 to 3 day delivery to the USA and 2 to 4 weeks international. You Will Not be Charged Shipping at Checkout. Make Sure you Choose the correct shipping destination in the drop down box below each item. Prices are all US Dollars (USD).




Yes, We ship Internationally (US Post Office)




This Kit has Everything You Need
Master Heat Sink and Cable Kit with GM OEM PMD and #9 Resistor

FSD Master Kit

395.00 each + 12.50 Shipping to USA

Canada shipping 49.00
International Shipping 67.25
(prices below include shipping)

Ship-to Destination

Heat Sink and Cable Kit

FSD Cooler Kit

163.00 each + 9.00 Shipping to USA

Canada shipping 44.00
International Shipping 63.25
(prices below include shipping)

Ship-to Destination


Cable Only

Cable

118.00 each + 9.00 Shipping to USA

Canada shipping 44.00
International Shipping 63.25
(prices below include shipping)

Ship-to Destination


GM OEM PMD with #9 Resistor

Cable

260.00 each + 9.00 Shipping to USA

Canada shipping 44.00
International Shipping 63.25
(prices below include shipping)

Ship-to Destination


GM OEM PMD Only

Cable

236.00 each + 9.00 Shipping to USA

Canada shipping 44.00
International Shipping 63.25
(prices below include shipping)

Ship-to Destination


PMD Details

Note: The FSD/ PMD (same thing) is a small black box on the side of your injection pump. It is a signal amplifier that powers the fuel solenoid on your injection pump. It has 2 transistors mounted on it's backside that generate heat that has to be dissipated. In it's stock location it can over-heat and fail.

Stanadyne DS-4 Injection pump

New PMDThe story usually begins like this. You’re driving along and the engine just quits. You lose your power steering and the truck is very hard to steer. You pull over to the side of the road and you are able to restart. As time goes on the stalls become more frequent and the truck gets harder to start.. You realize that you can’t trust the truck and something has to be done. This is the classic symptom of a failing Fuel Solenoid Driver (FSD) also known as a Pump Mounted Driver (PMD). This is an electronic switch that controls the fuel flow on a Stanadyne DS-4 electronic injection pump. Electronic injection pumps are used on all Hummers, trucks and vans with the GM 6.5 turbo diesel. A failed FSD will not display an engine light. Pictured above the FSD is a small black box about the size of a deck of cards bolted to the side of your injection pump. It is an amplifier that receives signals from the engine computer to pulse the fuel solenoid which tells the injection pump to send fuel to the engine. It has 2 power transistors mounted on the back that generate heat that has to be dissipated. The injector pump is mounted deep in the center valley of the engine in a very hot environment. The FSD is exposed to heat that can cause it to fail over time.

The Stanadyne DS-4 pump has been used on GM trucks since 1993. Owners of older Chevy and GMC trucks and G-Vans have experienced these problems years before Hummer owners have. GM had so much trouble with early generation electronic injector pumps that they had to warranty the units for 100,000 miles. When AM General purchased these motors from GM they did not get a 100,000 mile warranty. In 1999 AM General bought the plant and took over production of the 6.5 engines later that year.

Injector pump burried in the engineHeat generated by the PMD is supposed to be carried off by the diesel fuel flowing through the pump.  While this is true, the damage is being caused right after the engine is shut down.  After you stop the engine the fuel of course stops flowing and the water pump stops circulating coolant which in turn causes the engine temperature to actually spike for a short time.  This is called heat soak.  This rise in temperature heats the PMD which is bolted to the injection pump sitting on top of the engine.  The continual heating and cooling cycles cause the PMD to fail over time.

Note that damaged wiring or a bad injector that's drawing too much current can take out a PMD. Also check the the fuel system shutoff solenoid on the injection pump. An electrical problem here will cause the engine to die.

Because the injection pump is deep in the valley of the engine the PMD mounting screws are almost impossible to get at unless you remove the manifold (which is a major job. I've spoken to a couple of mechanics that were able to get the PMD out by using a very short torx bit wrench but I can't see how it was done.

If your PMD needs replacing it seems unwise to put it back where it was, down in the heat. Why not save all the trouble and labor and simply mount the PMD on a heatsink somewhere away from the engine where it can stay cool.

Flash Off-Road has a specially designed heat sink and extension cable that let you remote mount your PMD in a cooler spot. The kit used in this article is from Flash Off-Road. This solves the problem once and for all.

PMD Calibration ResistorPMD’s have a calibration resistor pack that describes the pump to the electronic control system. There is variability in the manufacturing of injector pumps where some output a little more fuel and some a little less. When GM or AMG sell the engines they specify the hp. In order to make sure that all the engines they produce output the same power they use the resistor to calibrate the engine computer to the pump. The #5 calibration resistor is considered the "average", but any pump will work with any resistor. Most owners replace the resistor with a #9 because it gives them a little more fuel and possibly a little increased performance.

The resistor pack is a small circuit board with a resistor that is inserted deep into the PMD’s socket. New PMD’s don’t come with resistors. The resistor is only used when the control computer forgets what the value is, which occurs after the batteries are disconnected or a hard reset is performed with a tech tool. If you don't use a resistor you will get a p1218 error code when the computer tries to read the value. Your truck will still run.

Whenever I run into a failed PMD I always replace it with a remote mounted unit on a heatsink and just abandon the defective PMD on the injection pump. Read More