Direct Oil Cooling, Part 2

Diesel Articles

duramax-oil-cooler-installed-371x184Discover why direct cooling, properly engineered, offers the only solution that can control 1. Oil temperature, 2. Viscosity and 3. Flow rate to design specification limits under high load/high RPM conditions.

The Black, White and Greys of the Duramax Fuel Filter

Diesel Articles

Grandpa operating Case 1150B series dozer with scraper

Grandpa used to lecture me about the importance of draining the water separator on his farm’s diesel tractor. This man, who wouldn’t hesitate to fix things with haywire or binder twine was, however, a purist when it came to maintenance. Experience had taught him that draining the water separator could mean the difference between a well performing engine and one with problems – or one that didn’t run at all.

The investment required to properly maintain the fuel system meant avoiding the corrosion and scoring caused by water when it runs amok in the fine-tolerance components of a diesel engine.

Duramax engines are significantly more sophisticated than Grandpa’s tractor. One might think that these more sophisticated engines can look after themselves a little better. In a sense that is true: today, we have more feedback than ever coming from our engines. But to think that these engines can handle not being maintained as well as their less sophisticated forerunners is far from the truth. In fact, just the opposite: today’s fuel injectors and other components require much higher tolerances. Consider that a typical conventional diesel fuel system prior to the DMax operated at fuel pressures of 1,200 to 1,500 PSI. Then compare those numbers to the original LB7 fuel injector that operated in the range of 4,500 to 23,200 PSI!


Lube Notes: Motor Oil Formulation



The last issue of maxxTORQUE Lube Notes explained the regimes of lubrication including Hydrodynamic Lubrication, Boundary Lubrication and Elastohydrodynamic Lubrication. As promised, I will now talk about the formulation of motor oils and why we put all those additives in our oil. Before we get into the formulations of the motor oils, we better take a look at the functions of motor oil. If we understand what oil is doing, then we can better understand why we choose certain base stocks and additives.

Motor oil must perform the following functions:

  • Lubricate engine parts in order to prevent wear
  • Reduce friction and improve fuel economy
  • Maintain clean engine components
  • Prevent rust and corrosion
  • Minimize engine deposits
  • Provide engine cooling
  • Aid in engine starting
  • Provide ring seal for better combustion pressure

Each of these functions is vital to optimum performance as well as to the durability of the internal combustion engine. Motor oils are complex lubricating fluids carefully formulated to perform all of these functions.


$100 a Barrel Oil


coal-liquefactionIn my last column I predicted oil would exceed $100.00 per barrel and unfortunately that prediction has come to fruition. It would be great to say that I had mystical powers of seeing into the future but the prediction was a no brainer. Supply is limited and demand is on the rise: the only possible outcome is increasing prices. So, without fanfare, I now predict oil at $125.00 a barrel by mid summer. World reserves of crude oil are actually higher now than at anytime since the 1974 oil embargo, but as I detailed in Issue One the world oil market is now a commodities market and the price fluctuates with speculation. OPEC is toying with reducing production to insure prices stay high in the event of a worldwide recession. In the end, we here in the USA will see rising prices for everything we buy, not just diesel and gasoline.


Shop Wants a Lot of Money to Fix My Heater Problem

6.2/6.5 Issues and Answers

I bought my 1996 half-ton 6.5 pickup used and do not know its history. I do know that I am freezing now that winter has set in – the heater is lousy and I cannot keep the windshield free of ice. The temperature gauge stays at about 160ºF most of the time and that looks hot enough to me, so I don’t understand what is happening here. A local shop told me that the radiator and heater core were plugged and they estimated $1,085 to fix these. Can you give me some help – something better than $1,085?


99 Suburban Starts Rough When Cold

6.2/6.5 Issues and Answers

Our 1999 Suburban has been a great family car and it has always run well, except for the PMD problem (now fixed). It has 175K miles on it. The problem we are having now is that it does not start well the first time each day. It starts quickly but then shakes, misses and smokes for about 10-15 seconds. Then suddenly, it will straighten up, run smooth and the smoking stops. The local dealer shop told us it needed a new fuel injection pump, but I am not convinced. What should we do?


1995 K2500 Has Had 6 Injector Pumps

6.2/6.5 Issues and Answers

My 1995 K2500 GMC has had six injection pumps put on it since new. Each time the shop replaces the injection pump, the truck runs like new again – for a year or two. The last time we had this done, our mechanic installed a different fuel delivery box. He said that the one mounted on the injection pump was the problem all along, so he installed this new one that is fastened to a finned cooling grid that bolts along side the intake manifold. He said that this would solve the problem we had been having. Well, it has not worked out that way. After 13 months and 23,000 miles, we are right back where we always seem to wind up – with a stalling engine. A friend gave me your magazine and I am thrilled to find information about my truck. I hope you can offer some suggestion that might help us fix this for a longer period of time – we need reliability!


'96 6.5L Diesel Acting Up

6.2/6.5 Issues and Answers

I love my ’96 dually, but have been having problems: My fuel mileage is down to only 13 on the highway and the throttle has become very goosy or jumpy. Often times, while waiting at a stoplight, the engine will surge and blow out a big puff of smoke. One time, it revved way up and I had to turn off the key to stop it. Then it started again and ran fine. It seems to have a mind of its own and I just don’t trust it anymore. Can you help?


6.5L Diesel Runs Hot When Towing

6.2/6.5 Issues and Answers

A mechanic told me that all 6.5’s run hot when towing a heavy load, but I am not so sure he knows what he is talking about. When we are going uphill with the camper and boat, the gauge goes over to about the three-quarters mark, but it didn’t used to go that far. I think something is wearing out or getting weak. Any ideas?


No Power to Pass with My '94 6.5L Diesel

6.2/6.5 Issues and Answers

My 1994 three-quarter-ton 4x4 truck seems to run fine – until I leave the city and try to run at higher speeds. I don’t even try to pass anyone – it will fall on its nose if I stay in the power. Sometimes it dies when I go around a corner in town and step on the throttle. Do you know what might be wrong?



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