Shift Pointers Archives - Page 3 of 18 - Transmission Digest
GM 10L80: A new kind of pump noise

How quickly time passes by. The GM 10L80/90 transmissions began production in 2017, meaning that we’re closing in on six years of this transmission being on the road. Many who work in the dealerships have become privy to the immediate failures that occur in this unit. And now, with some of these transmissions coming out

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Common failures on the GM AW55-50SN

GM’s AW55-50SN, otherwise known as the AF33 transmission (figure 1, above), is known for its placement in vehicles including the Chevrolet Equinox and Captiva, the Pontiac Torrent and the Saturn Vue. Versions of this transmission can also be found in SAAB, Volvo and Nissan vehicles. This unit began being produced in 2000 and ended production

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A misleading code: Finding the right solution to the right problem

In having the privilege of presenting at Worldpac’s Supplier and Training Expo in Orlando Florida earlier this year, I met a couple of instructors from the Daytona State College who attended my seminar: Beau Bosman and Casey Knecht. During my presentation, I covered an issue with an Allison 1000/2000 that had the converter clutch cycling

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A Chevy Volt making noise

There is a Preliminary Information (PI) paper published by GM regarding a concern with 2011 to 2013 Chevy Volt using a 4ET50 transmission. The PI paper explains that some customers may comment on a whistle, scrape or whine type noise while driving that may be more noticeable during regenerative braking. Technicians may find this noise

Common problems with uncommon solutions: 6L45 no-move or slipping forward

A 2010 3.0L Cadillac AWD CTS using a 6L45 transmission comes into the shop with a no-forward complaint. This particular vehicle is known for having the output shaft suffer from fretting, in which the output shaft to transfer case input shaft spline will strip and cause a no-move (figures 1 and 2). Sometimes, due to

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No forced throttle downshifts

Twenty-five years ago, Chrysler introduced a 0.187-in. (4.77mm) steel, #10 check ball (figure 1, above) in the 42RE valve body which continued to be used throughout the entire RE series of transmissions (42, 44, 46, 47 and 48RE) as they were launched. This small check ball is quite active, having several functions during the course

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Fixing JF011E primary pulley pressure sensor issues

A 2.4L Dodge Caliper using a JF011E CVT2 transmission developed a problem with the Primary Pulley Pressure sensor. A low circuit error code P0842 was pulled from the TCM. The sensor ground and 5-volt wiring circuits were checked and verified as good. The signal wire was then inspected and was also verified as good. There

62TE overheat discoloring: A brand new issue

Just when you might think you’ve seen everything that can happen to a transmission, Bob Perry from Fischer Transmissions uncovered what might be a brand-new issue. In this case, the car was a 2015 Pro Master with a 62TE transmission that was in failsafe with Code P0883 for TCM Power Input High. This means the

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Dealing with GM 6L series rebuild issues

During a rebuild of a GM 6L80 transmission, while the valve body was being serviced, an incorrect spacer plate was accidentally used. This blocked supply pressure to the 3-5-R regulator valve which prevented the 3-5-R clutch from applying. One of the more significant changes made to the valve body for 6L80 series transmission is related

Shift pointers: 6T40 neutral drop

A 2011 1.8L Chevy Cruze showed up to the shop with a slipping generation one 6T40 transmission. Engagements were good, but on a quick initial road test it would flare to neutral when the 1-2 shift was commanded. Then it might drop in and hold second gear or shift to third gear and seem okay. 

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2016 Nissan Altima: What to do with a defective TCM

Nissan vehicles that produce Judder codes DTC P17F0 and/or DTC P17F1 in many cases will be a defective TCM. One sure way to know is to document and clear all codes. Then, keep the ignition on for a bit without the engine running. If the code returns, a defective TCM has been confirmed requiring a

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A 6T70 IMS Invalid Range Signal

There are four inputs to the TCM from the position switch assembly, that indicate which transmission gear range has been selected.