Your Diesel Truck Is Overheating and You Don't Even Know It
About this episode
It's towing season and if your gauges are climbing on the way up the grade, you need to know what's actually normal and what's a real problem. Will and Myer break down coolant temps, transmission temps, and everything that can push a Dodge Cummins diesel truck out of range while towing.
They start with what a healthy cooling system looks like going down the road. Thermostat opening temps on these trucks typically run 180 to 200 degrees depending on year and setup, and they explain why a hotter or cooler thermostat matters for winter heat versus summer towing, along with how boiling points, radiator cap pressure, and elevation all affect what your coolant temperature can handle.
A big part of the episode covers fan clutches, since a bad cooling fan clutch is usually the first thing they check when a diesel truck runs hot. They explain how to tell if your mechanical fan clutch is engaging and why electric fans aren't actually an upgrade over the factory setup on these Cummins trucks.
From there they walk through testing a thermostat the old school way with a pot of boiling water, the bypass port a lot of guys don't know exists in the block, and why a genuine Cummins thermostat is worth it over the cheap parts store version, especially on a second gen Dodge.
Radiator condition gets its own conversation too. They cover why a clogged or dirty radiator causes most cooling problems, why a factory copper core radiator often beats a cheap aftermarket one, and how they've flushed old radiators back to life with everything from radiator flush products to straight vinegar. They also get into heater core plumbing and why oversized fittings from a repipe can hurt your cooling in the summer.
The conversation wraps up on transmission cooling, the second gen's heat exchanger setup, why factory transmissions are designed to run around 185 degrees, and why colder fluid on a built performance transmission tends to live longer.
Along the way Will and Myer share real diesel towing stories, from Willard's cooling performance on a run to Saint George to a second gen Dodge gauge that pegs out hard at 230 degrees, plus a few lessons learned the hard way about fan clutches and stuck thermostats.
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Will and Myer reference several parts from their own builds throughout the episode, including compound turbo setups, VGT turbochargers, and stage two and stage three injectors. Shop everything mentioned in this episode at PowerDriven.com links below.
Shop Power Driven Diesel: https://www.powerdriven.com
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