Ford’s historically coveted Power Stroke 7.3 engine was considered one of the most reliable diesel motors in the Ford truck series, with some owners clocking well over 500,000 miles on it with no engine work needed (except possibly replacing the HPOP–high-pressure oil pump). If you were one of the lucky ones to have the ZF5 transmission, then you really had the full package.
It’s common knowledge the majority of Ford truck enthusiasts consider the 7.3-liter Power Stroke the greatest diesel motor put inside a pickup truck. Some might even argue that it was the best engine ever put into any Ford period. Sadly, for the past 15 years, the great and revered 7.3L has been out of production. However, it is virtually impossible to disregard the impact it had on America’s heavy-duty truck history.
International Harvester and Ford: Dreamteam
Back in 1978, International Harvester (IH) began working on an 8-cylinder motor for medium-duty trucks. The idea was based on IH’s 446-CID industrial gas V8. Not to be mistaken for a conversion, this new concept diesel motor was in its initial stages of revolutionizing the diesel market. The 7.3L Power Stroke came to life as a replacement for the aging 7.3 IDI (indirect injection) and, in 1981, a $500 million five-year agreement was signed between the two giants–IH and Ford.
A Little History
In 1982, before the Power Stroke was even known by that name, General Motors had the very economical 6.2-liter Detroit diesel in their pickup truck lineup. Ford knew right away they had come up with a way to compete for a steady new spot in the diesel truck market. The answer came by utilizing and leveraging the diesel engine’s high torque levels and maximum power at low revs. This, in turn, resulted in better efficiency.
Only one year after the Detroit diesel came out, Ford released the 6.9-liter IDI diesel engine. The IDI, which was originally produced by International Harvester, got its name for its indirect fuel injection system. Even though it was a naturally aspirated motor, the 6.9-liter IDI output a very respectable (remember this was the 1980s) 170hp and 315-340 lbs. of torque.
This first-generation Power Stroke, a combination of a simple, overhead two-valve design with conservative power ratings, resulted in a good motor that could last 300,000 miles and beyond. The 6.9L proved to be extremely durable, very reliable and had excellent fuel economy.
The truck world eagerly greeted that very first Power Stroke diesel. Not long after the next generation, Ford Super Duty truck was released, which became known as the amazing 7.3L IDI diesel engine–produced from 1988-1993. The new IDI’s displacement resulted in boosted horsepower and torque, and it was still a naturally-aspirated engine.
In 1993, much to the delight of Ford truck die-hards everywhere, the IDI was finally given a turbocharger, which cranked out 190 horses and 388 lbs. of torque. The world now had a V-8 displaced 444 ci (7.3L) motor that was direct-injected, turbocharged and featured a hydraulically actuated, electronically controlled unit injector (HEUI) fuel system.
In 1994, the 7.3L motor’s name became its own trademark and namesake. In addition to the direct injection and newly added turbocharger, the motor included an HPOP. The transition to HEUI improved fuel economy, performance and lowered emissions.
7.3 Liter Power Stroke Pros
- 6 head bolts per cycle
- 290 to 325 rear wheel horsepower with a chip
- No emissions system
- Fixed geometry turbo = more reliable
- Great Low-End Torque due to 444 cubic inches of displacement
- Higher resale value
- Very reliable injection system
- The 7.3-liter Power Stroke was different from the 7.3-liter IDI in one very important area: The Power Stroke used an electronically-controlled fuel system with direct injection instead of a mechanical fuel system with indirect injection. This resulted in a lot more power.
- Varying in production years and drivetrain specifications of the Ford Super Duty, the 7.3-liter Power Stroke produced 215-275hp and 425-525 lbs. of It was, and still is, considered to be one of the greatest diesel engines ever made.
Sadly, the 7.3L Power Stroke ceased production in 2003. Due to newer emission requirements, it was replaced, but it is still one of the most popular engines of today.
Regarding durability and reliability, the 7.3L Power Stroke is the leader in standards when it comes to consumer approval. Blue Oval loyalists, who have been in the diesel truck motor game for the past 20 years, will no doubt attest to that.