5-Speed Manual Truck Transmission NVG 1500 (MW2)
5-Speed Manual Truck Transmission Aisin AR-5 (MA5)
2005 Model Year Summary
· There are no changes for 2005
LOW MAINTENANCE
The 5-Speed Manual uses Esso 75W90 for lubrication. There is no maintenance required under normal operating conditions, although fluid changes are recommended for severe duty. A GM part number service oil is available from GM dealers.
OVERVIEW
To achieve car-like standards in running noise and shift quality, the proven Aisin AR-5 was selected for the new Chevrolet Colorado and GMC Canyon (GMT355) compact pickup truck line. This transmission will handle the torque output of the base and uplevel engines, which will reduce assembly and service complexity compared to the previous S-series compact pickup line’s availability of two manual transmissions for base and uplevel engines.
The four-cylinder 4wd model with manual transmission of the previous compact pickup was discontinued in the early 1990s. The new transmission with the new Vortec 2.8-liter inline 4 engine allows an entry into that segment of the market.
The design and performance targets were supplied to Aisin by GM Powertrain to make the AR-5 a state-of-the-art manual light-duty transmission (New RPO MA5). The AR-5 is currently used by Isuzu and Toyota, although the gearsets and ratios for the GM application are unique.
The Aisin AR-5 was selected as a starting point because of its characteristic low-noise levels during operation and the light shift feel and smooth gear engagement properties. The Aisin unit is used in competitive sport-utility applications, meeting car-like noise standards.
The Aisin 5-speed transmission is a conventional two-axis manual gearbox, with a through shaft and a counter shaft, spaced 82mm apart on-center. It is cast in aluminum, and weighs 107 pounds, which is 5 pounds heavier than the New Venture Gear 1500 (MW2) 5-speed manual available in the previous compact pickup line. It has been certified for 225 lb. ft. of torque for use with the uplevel inline five cylinder engine. The gear selector pattern is conventional for a five speed manual transmission, with the reverse gate on the far right side and rearward. The shift lever connects directly to the top of the transmission.
Triple-cone synchronizers are used on 1st, 2nd and 3rd gears. These synchronizers have three friction surfaces, which increase their ability to transfer the flow of torque more smoothly from one gear to another. Synchronizers act as clutches to speed up or slow down the gearsets that are being shifted to, and greater friction area results in easier shifting for the driver. All of the friction surfaces on the synchronizer rings are brass. The ratios in the 5-speed are widely spaced for versatile performance and efficiency, and are optimized for both the base inline four cylinder and the uplevel inline five cylinder engines. Both engines share the same ratios.