Performance Goodies
The input shaft is upgraded from a “necked down” 23 spline shaft to the Ultimate proprietary billet steel input shaft—which is a larger, custom 35-spline two-piece design that requires a custom torque converter and was found to be stronger than the one-piece design.
The Intermediate shaft is also replaced with a larger billet shaft. The stock 23-spline tail shaft is improved to a proprietary billet 29- spline shaft that increases strength by 20 percent plus over a 23-spline billet shaft.
This modification requires the input shaft on the transfer case to be enlarged to a 29-spline shaft, the same input shaft that is used on manual transmissions.
The larger 29-spline input shaft is used with standard transmissions. The stock shafts are on the left. It’s easy to see the difference in diameter of the shafts, which are significantly increased with the 29-spline Ultimate input shafts.
The planetary gear housings that get used are fully-welded instead of the spot/tack welded style that are used in stock transmissions
Yet another impressive feature to be found on this build was the deeper direct clutch hub, which allows for an extra clutch and steel to engage. Normal clutch hubs would drop the last clutch. They use a proprietary aluminum alloy that is as difficult to cut as steel. It is a billet aluminum versus the cast aluminum used on stock. Another alternative being used by competitors is to anodize the finish on cheaper aluminum to achieve a surface tension that may hold up. Ultimate Transmission uses the better aluminum so they know it will hold up. Simply put, better materials, better transmissions!
On the forward clutch drum oil feed, the factory uses barbaric plunge cuts for oiling. Ultimate Transmission uses billet drums with machined ports that are more efficient and provide oil flow to the piston.
This creates a smoother radius for better connection with far less cavitation, and provides a more fluvial oil flow for more even clutch engagement.
After all of the internal parts of the transmission are assembled, checked for proper spacing, and put into the case, the oil passages are filled with transmission fluid and pressurized with air to check for proper engagement and seal of all clutches and bands.
High resin is used for the holding clutches and carbon Kevlar hybrid is used for shifting clutches, increasing the holding capacity over stock clutches. Valve body is disassembled and inspected. Depending upon the shifting firmness that is desired, oil passages can be enlarged to allow more fluid to different areas of the transmission for firmer engagement of the clutch and or band.
When the valve body is thoroughly checked and the proper modifications are made, it will assure the desired firmness of shifts will be achieved. The valve body is then tested to ensure that all components are functioning properly before being put on the transmission.
All bolts are hand-torqued to the proper specs using a torque wrench and the torque converter is pre-filled with transmission fluid and installed onto the input shaft of the transmission.
Ultimate Transmission has custom torque converters made just for their transmissions that come in a wide variety of stalls and can be made to order from stock to extreme.