GM Transmission Information (Looking for Engine info?  Click here)

Click here for: 440-T4 / 4T60 (non electronic) ID charts

Front-Wheel Drive Transmissions

4T40-E / 4T45-E

• FWD 4-speed automatic with overdrive
• 187 lbs transaxle weight filled
• Gear Ratios:
•    1st -- 2.960
•    2nd -- 1.626
•    3rd -- 1.000
•    4th -- 0.681
•    Rev -- 2.143
• Final Drive Ratios: 3.05, 3.29
• Available Chain Ratios: 35/35, 33/37, 32/38

4T60-E -- click here for Application ID charts

• FWD 4-speed automatic with overdrive
• 204 lbs transaxle weight filled
• Gear Ratios:
•    1st -- 2.921
•    2nd -- 1.568
•    3rd -- 1.000
•    4th -- 0.705
•    Rev -- 2.385
• Final Drive Ratios: 2.84, 3.06, 3.33
• Available Chain Ratios: 35/35, 37/33, 28/27, 33/37

4T65-E -- click here for Application ID charts

• FWD 4-speed automatic with overdrive
• 214 lbs transaxle weight filled
• Gear Ratios:
•    1st -- 2.921
•    2nd -- 1.568
•    3rd -- 1.000
•    4th -- 0.705
•    Rev -- 2.385
• Final Drive Ratios: 2.84, 3.06, 3.33
• Available Chain Ratios: 35/35, 37/33, 33/37

4T80-E

• FWD 4-speed automatic with overdrive
• 293 lbs transaxle weight filled
• Gear Ratios:
•    1st -- 2.960
•    2nd -- 1.626
•    3rd -- 1.000
•    4th -- 0.681
•    Rev -- 2.130
• Final Drive Ratios: 2.84, 3.11, 3.48, 3.71

FWD Transmission Gearing / Chain Information Table

Rear-Wheel Drive Transmissions

4L60-E

• RWD 4-speed automatic with overdrive
• 159-176 lbs transmission weight filled
• Gear Ratios:
•    1st -- 3.059
•    2nd -- 1.625
•    3rd -- 1.000
•    4th -- 0.696
•    Rev -- 2.294
• Max Gearbox Torque: 670 ft-lbs

4L80-E

• RWD 4-speed automatic with overdrive
• 260 lbs transmission weight filled
• Gear Ratios:
•    1st -- 2.482
•    2nd -- 1.482
•    3rd -- 1.000
•    4th -- 0.750
•    Rev -- 2.077
• Max Gearbox Torque: 885 ft-lbs

5L40-E

• RWD 5-speed automatic with overdrive
• 186 lbs transmission weight filled
• Gear Ratios:
•    1st -- 3.42
•    2nd -- 2.21
•    3rd -- 1.60
•    4th -- 1.00
•    5th -- 0.75
•    Rev -- 3.02
• Max Gearbox Torque: 494 ft-lbs

GM RWD Torque Converters

Starting 1980-up, GM used a 4-digit ID sticker located on the converter body to help identify it.  Below is a guide to help decipher it's meaning.

1st Digit (application trans)

• B -- THM250C, THM350C
• C -- 200C, 2004R, Pre-1984 1/2: 325-4L & 700r4
• D -- 1984 1/2-up 700r4, 4L60, 4L60-E

2nd Digit (approx stall, depends on engine)

• B -- 2025 rpm
• C -- 2075 rpm
• E -- 1654 rpm
• F -- 1611 rpm
• G -- 1397 rpm
• H -- 1397 rpm
• K -- 1211 rpm
• L -- 1654 rpm

3rd Digit (Clutch Assembly)

• 3 -- Poppet Valve
• 7 -- Poppet Valve
• 9 -- Poppet Valve
• A -- Red (pre-96)
• A -- Carbon (96-up)
• B -- Static Open
• G -- Carbon Fiber
• H -- Red (pre-96)
• H -- Carbon (96-97)
• H -- Woven Graphite (98-up)
• L -- Carbon Fiber
• N -- Woven Graphite
• P -- Woven Graphite

4th Digit (Body Mounting)

• C -- 3 round lugs, gas engine
• D -- 3 round lugs, diesel engine
• E -- 6 round lugs, gas or diesel
• F -- 3 square pads, gas or diesel
• G -- 3 square pads, gas or diesel

If there is no ID tag, there might be a number or letter stamped between the dimples of the impeller on the converter body.

• 4 -- 1211 stall
• 5 -- Medium or high stall (depends on stator)
• 6 -- 1397 stall
• 7 -- 1654 stall
• C -- 2075 stall
• H -- 1397 stall
• K -- 1211 stall
• L -- 1654 stall

GM FWD Torque Converters

GM uses the same type 4-digit ID method of identifying FWD torque converters as with the RWD units, however the digits have different meanings.  All 125-C, 440-T4, 4T60, and 4T60-E transmissions use the same style torque converter, and they are interchangeable before 1996.  1996-up converters are built to be compatible with GM's PWM TCC apply strategy which means that you can use the newer converter on the older trans, but not the older converter on the newer trans.

1st Digit (application trans)

• F -- 125C, 440-T4, 4T60, 4T60-E (245mm)
• J -- 4T65-E HD (258mm)

2nd Digit (approx stall (depends on engine)

• A -- 2795 rpm
• B -- 2560 rpm
• C -- 2385 rpm
• D -- 2095 rpm
• E -- 1865 rpm
• G -- 1630 rpm
• H -- 1515 rpm
• J -- 2060 rpm
• K -- 2760 rpm
• L -- 1895 rpm
• M -- 1525 rpm
• Y -- 1420 rpm
• Z -- 2375 rpm

3rd Digit (TCC clutch material)

• 0 -- Clutch omitted by factory
• 5 -- Clutch contains poppet valves

All other digits (pre 1996): 

• Red Fiber material

1996-97

• C, E, H, K, P -- Carbon filled clutch

1998-up

• F, H, K, Q -- Woven graphite clutch

4th Digit (Clutch Type)

• B -- standard
• C -- viscous

Pertaining to the TCC Clutch material: starting in 1996, GM implemented a new TCC apply strategy.  The 1996-97 trannys (exc 3T40), used a soft-apply (PWM) TCC strategy which was designed to soften the TCC apply so the "customer" would not feel it come on.  This means that the PCM is actually making the TCC slip during apply.  Only Carbon clutch torque converters should be used in 1996-97 trannys.  You can use the carbon clutch TC's in earlier trannys that did not have PWM technology, however the lockup feel will not be the same.  However, I have heard that these carbon clutches rarely burn-up or go bad.  I have personally used the carbon filled clutch TC's on earlier trannys and the only experience I have witnessed with them is they apply firmer.

Starting in 1998, GM revised the lock-up strategy once again only this time the TCC may never completely lock up and may always slip about 20-60 rpm, depending on the vehicle.  This means that even the carbon clutch units would not work well for these applications thus GM started using woven-graphite TC clutch material.  I have heard that the woven graphite TC's should not be used in any earlier transmissions because the lockup will not work correctly.

This information should be used as a reference guide only.  Please consult your local dealership or transmission shop for your specific application and needs.

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