The Tremec design T-5 5 speed transmission has been around since the early 80's. "World Class" models were introduced in 1985. These transmissions feature tapered roller bearings on the cluster, caged needle bearings under the 1st, 2nd and 3rd speed gears on the mainshaft, double synchronizers on 1st and 2nd and steel blocker rings with bonded friction materials. Ford adopted this configuration for 1985 and up production T5's. Similarly, all Ford aftermarket T-5 applications have been "World Class" since 1985. As the demands on this transmission were increased, gear materials were upgraded (8620 to 4620 to4615) and blocker ring lining materials went from paper to carbon fibre.
In 1993 the pocket bearing between the input and mainshaft was changed from a needle bearing to a tapered roller bearing. This was only used in production on the '93-95 Mustang Cobra T5's but was adopted on many high performance aftermarket T-5 applications including the m-7003-z. The T-5 design and manufacturing rights were purchased by Tremec in 1996 and is still being produced in Mexico.
This is the initial build of a my custom 7003-z spec trans from a repurposed WC case, hardened alloy gears, pocket bearing 2.95 input (not needle bearings) from a new distributor based out of Texas, a 070 spec chromoly gear cluster, a unique uncommon 2000 mustang rear case with electronic speedo, and a billet gear pack retainer. Should be plenty of fun at half the price of a frpp 7003-z trans and plenty for my street 450hp 347.
Here is my coveted T5 1993 Cobra mustang input shaft (aka m-7003-Z). This piece is going for hundreds of dollars for used parts but with the new SAE 8620 alloy you can have this kit built for much cheaper as we are experimenting with the Frankenstein. I came across them online.
The differences between the two bearings inside the cup are apparent here. The difference between a needle bearing world class setup (top) and the obvious race and bearing surface in my new input shaft cup (bottom). The input shaft rides directly against the gear output shaft and is either riding on the weaker needle bearings as seen in the T5 WC or they are riding on the tapered bearing and race as seen in the stronger t5 cobra aka t5z input shaft.
The shaft on the right has a smaller surface area on the front side of the output shaft, and the weaker WC is on the left.
Here you can see the installed bearing on the t5z shaft and how it sits in the above input shaft. This is the stronger bearing that Ford even quotes as having 330 lb ft capability compared to the WC has 265 and 300 respectively depending on the gear count.
Billet cluster support plate. The rebuild kit comes with a thin sloppy metal retainer. This replaces that weak part.
Newer smooth t5 cover got rid of NSS hole and cleans up the overall look of the t5z+ frankenstein trans.
Then inside the cover i replaced the finger selector with a stronger 1 piece design.