When working with Holset based turbochargers, such as the Super 54 and Super 60, it is essential to follow proper installation procedures to avoid unn...

Depending on your model year, various options are available The early model years 6.2 and 6.5L all use DB2 mechanical injection pumps If the vehicle h...

While we always recommend our high flow plenum upgrade be paired with our turbos, some owners choose to use the stock plenum with an upgraded turbo. ...

The TORQUE application is an Android app that can read codes and display live data for any OBDII vehicle. We have expanded on the default functionali...

This guide provides step-by-step instructions for setting the timing on a DS4 injection pump using a scan tool with TIME SET and TDCO Learn capabiliti...

Scan tool is essential for proper diagnosis 1994-1995 models: OBD1 system 1996-2000 models: OBD2 system Diagnostic codes differ between year ranges Po...

This article is written for a new production Optimizer 6500 engine but can be applied to other builds, where applicable. During break-in, use CONVENTI...

Lift Pump functionality is a CRITICAL part of the fuel system on any diesel vehicle. The 6.5L is no exception. There are different requirements depend...

Pump/Tune Mismatch Verify stock chip ID number and ID number on the injection pump 5068 pump needs a 5068 tune All other pumps need a 5521 tune Incorr...

This article provides a comprehensive overview of the 6.5L Diesel EFI Systems, focusing on the operation and diagnostics of these engines. Three Stage...

Summary: This article addresses the question of whether the optional sensor filter harness is required for 1994 and newer 6.5L diesel engines with th...

Quadstar's stainless glow plug heat shields are made to be upgraded versions of the stock fitment. This means they are built to fit the stock exhaust ...

If you're dealing with issues with a Stanadyne DB2 mechanical pump, this guide will help you diagnose and potentially resolve common problems. Let's d...

To perform a Passlock system relearn, make sure the vehicle battery is fully charged, as it will be used for 30 minutes without the alternator for cha...

Customer Reports: " Pull out onto the main road, rpms only go to 2200 and no power. Lags at 2200 for a moment finally shifts to second gear. This repe...

Get the timing set and give us some data from your scan tool. We don't like to guess without data so you'll be scratching your head without doing this...

Having issues starting your diesel vehicle in cold weather? This guide provides tips to help diagnose and improve starting in temperatures as low as -...

All 1996 and later 6.5L vehicles utilize the OBDII protocol which will require an OBDII scanner to query codes from the DLC under the steering column....

Diagnostic Trouble Code (DTC) 1994-1995 Trucks use 8192 Baud Data (OBDI).  You can simply count flashes of the CEL/SES light on the dashboard after g...

1994-2002 GM Trucks, Suburbans, Vans, Hummers, and some later model Hummers as well. DS4831-5288, 5459, 5521, 5521S, 5521WE, 5942 These are all supers...

This post provides step-by-step instructions on how to properly time the DS4 injection pump on the GM 6.5L Turbo Diesel engine. We have divided the pr...

These are 3 digit identification numbers that will tell you the factory build options of your GM vehicle There is a sticker on the inside of the glove...

This is important because the tachometer signal comes from the alternator on all 6.5L diesel trucks. If the pulley size is wrong, then the tachometer...