The T5 is a popular 5-speed manual transmission used in a variety of Ford and GM vehicles. Whether you’re a car enthusiast, involved in restoration projects, or simply looking to understand your vehicle better, the GM T5 is something you’ve likely come across.
This article provides a comprehensive overview of the T5 transmission, including its different variations, where it was used, how to maintain it, and potential upgrades you might consider.
One key distinction to understand is the difference between “World Class” and “Non-World Class” T5 transmissions. Identifying which type you have is crucial for sourcing the correct parts and performing proper maintenance. We’ll dive into the details of these differences so you can keep your GM T5 running smoothly.
The T5 Transmission: A History
The T5 manual transmission has a long and interesting history, finding its way into a wide variety of vehicles over the years.
It all started in 1980, when American Motors Corporation (AMC) first used the T5 in some of its models. Borg-Warner later took over the design, intending to market it globally. They made improvements to the synchronizers, making shifting smoother.
Today, TREMEC manufactures the T5, continuing to refine and evolve the design.
The T5 became a popular choice for both Ford and GM vehicles. You could find it in everything from the Fox body Mustangs to the Chevy S-10 pickup and Camaros. Its versatility and relatively compact size made it a good fit for a wide range of applications.
World Class vs. Non-World Class T5 Transmissions
If you’re looking into T5 transmissions, you’ll probably run across the terms “World Class” (WC) and “Non-World Class” (NWC). Here’s what you should know about the differences between the two.
What’s different?
The main differences between the WC and NWC T5s are the bearing race (the WC has a Timken tapered race) and the strength of the internal components.
Non-World Class (NWC) T5 Characteristics
The NWC T5s were mainly used in earlier models and in vehicles with lower torque. Some common problems with these transmissions include seal damage, fluid loss, incorrect shifting, and bearing wear due to age.
World Class (WC) T5 Characteristics
The WC T5s have a number of improvements over the earlier models, including better synchros and bearings. They use ATF fluid (Dexron III) and feature an aluminum, top-loaded design with a single-rail shift linkage and tapered bearings.
The Borg-Warner T5 quickly became a favorite among manufacturers and hot-rodders alike. It was lightweight, compact, and fairly robust, and it had an overdrive gear that made it well-suited to a variety of applications.
T5 Gear Ratios and Torque Ratings
The Borg-Warner T5 wasn’t a “one size fits all” transmission; different gear ratios were used depending on the specific engine and vehicle application. For example, a T5 bolted to a V8 engine would have different ratios than one paired with a 4-cylinder.
Here are a couple of examples:
- The 1985 Ford World Class (WC) T5 for the 5.0L V8 had a 3.35 first gear and a 0.68 overdrive.
- The 2005-2010 4.0L Mustang T5 featured a 3.75:1 first gear and a 0.73 overdrive.
It’s also crucial to understand the torque ratings of different T5 models, especially if you’re planning a swap or upgrade. The torque rating indicates how much engine torque the transmission can safely handle. Exceeding this rating can lead to premature failure.
Here’s a look at some typical T5 torque ratings:
- 2.95:1 Non-World Class (NWC) T5: 265 ft/lbs
- 4-cylinder Ford and GM T5s: ~240 ft/lbs
- 1990-1993 Ford WC T5 V8 upgrade: 300 ft/lbs
- 1993 Ford Cobra Spec T5: 310 ft/lbs
- 2005-2010 4.0L Mustang T5 (2.95:1 gear set): 350 ft/lbs
T5 Transmission Oil and Maintenance
Using the correct type of oil is critical for keeping your T5 transmission running smoothly. Several types of oil have been recommended for the T5, including Dexron II, Dexron III, and 50wt gear oil. However, World Class T5s use automatic transmission fluid (ATF) fluid, such as Dexron III.
Regular oil changes are also important if you want to prolong the life of your T5 transmission. If you use your vehicle as a daily driver, it’s a good idea to change the oil every 2 to 3 years. If you use your vehicle for track racing, you may want to change the oil once or twice a year.
Using a high-quality synthetic oil can also extend the life of your transmission.
As one expert mechanic told me, “Oil is cheap, transmissions are not!”
T5 Upgrades and Enhancements
If you’re trying to coax a little more performance out of your T5, you may want to consider some upgrades.
Aftermarket Heavy-Duty Gear Sets
You can buy aftermarket heavy-duty gear sets that are stronger than the factory gears. But be aware that these sets can be pricey, and some users report that they don’t always hold up to the claimed capacity. Some aftermarket gear sets are rated to handle up to 600 ft/lbs of torque, so read the reviews and do your homework before you buy.
Cryogenic Treatment
Cryogenic treatment, in which metal parts are super-cooled, can improve the strength of the T5’s internal components by as much as 30%.
The “Z” Spec T5
Ford Motorsport offered the T-5Z, a performance version of the T5. This transmission was rated at 330 ft/lbs of torque, based on an expected lifespan of 100,000 miles.
To Conclude
The Borg-Warner T5 transmission is a legend in the automotive world. From its history and different versions to its wide range of applications and specific maintenance needs, the T5 has left an indelible mark.
Whether you’re replacing parts or performing routine service, it’s crucial to identify the exact type of T5 transmission you’re working with to ensure compatibility and proper function.
The T5 remains highly relevant for car enthusiasts, hot rodders, and anyone involved in restoring or modifying classic cars. Its versatility and relatively compact size make it a popular choice for a wide range of vehicles.
With a solid understanding of its nuances and proper care, the T5 transmission can provide reliable performance and driving enjoyment for years to come, proving that some designs truly stand the test of time.