4T65E Transmission Info
I found this info @ Triple Edge Performance - Home Page and thought that it would be well received here.

This page provides information about the GM THM-4T65E 4 speed Automatic fwd transmission/transaxle which is found in many 1997 and newer vehicles equipped with the 3800 engine and most 2000 and newer vehicles with the 3400 engine. This is a great trans and has been refined a bit over recent years and as many of you know has its shortcomings, especially when the mileage gets high or extra power is added.
If you have a question about something that you do not see on this page feel free to send us an email for more detailed information.

This transaxle is a fully automatic and electronically controlled. Shifts are all controlled by the pcm by two shift solenoids, line pressure is also fully electronic and controlled by a Pressure Control Solenoid, or EPC which is commanded by the pcm. This transaxle also employs the use of a Torque Converter Clutch, or TCC and is used to further enhance gas mileage and keep engine rpms lower. The TCC style in this trans is a PWM type, which stands for Pulse Width Modulation. This style PWM TCC system was developed to allow for a smooth engagement of lockup and allows constant slippage of the TCC and can apply in 2nd through 4th gears. The constant slippage is tolerable to the converter because of a special TCC lining developed especially for this purpose and is called a Woven lining. An ordinary TCC clutch would burn up and shudder vilently if used in this type of system.

-Below are the gear ratios for each gear of the transmission

1st 2.92:1
2nd 1.56:1
3rd 1:1
4th (OD) 0.70:1
Reverse 2.38:1

There are numorous gear ratio combination options for the 4T65E transmission and below are ratio options that can be found

-Final drive-differential ratios

2.86:1 in standard differential only
3.05:1 in standard differential only
3.29:1 in standard differential and also the HD (Heavy Duty) and Volvo version differential

-Drive and Driven sprocket combinations and ratios

33 Drive / 37 Driven creates a 0.892:1 ratio
35 Drive / 35 Drive creates at 1.000:1 ratio
37 Drive / 33 Driven creates a 1.121:1 ratio

The Drive and Driven sprocket ratio will directly factor in to calculate the overall transmission ratio. For example most of the Supercharged 3800 powered vehicles come with a 3.29 HD differential but they have a 37/33 sprocket orientation and this will overdrive the transmission and create an overall ratio of 2.93:1



-Here are the resistance specs on the internal solenoids

Connect Pins Solenoid Resistance at 68*F 190*F Shift Solenoid Patterns for each gear

A-E 1-2 Shift Solenoid 19-24 24-31 Range 1-2 Solenoid 2-3 Solenoid
B-E 2-3 Shift Solenoid 19-24 24-31 Park ON ON
T-E TCC/PWM Solenoid 10-12 13-15 Reverse ON ON
C-D EPC Solenoid 3-5 5-6 Neutral ON ON
S-V Input Speed Sensor 893-1127 1132-1428 1st Gear ON ON
M-L TFT Sensor 3164-3867 225-285 2nd Gear OFF ON
Output Speed Sensor 981-1864 3rd Gear OFF OFF
4th Gear ON OFF
Below are the Torque Specs for the 4T65E

Description Thread Size Lb.Ft. Lb.In.

Bottom Pan Bolts (mid 98+) M6 X 1.0 X 17 10
Side Cover Bolts M8 X 1.25 X 25 18
Side Cover Bolts ( Torx head ) M8 X 1.25 X 21 18
Final Drive Housing Bolts M10 X 1.5 X 35 26
Forward Servo Cover Bolts M6 X 1.0 X 20 106
Vehicle Speed Sensor Bolt M8 X 1.25 X 12 106
Drive Sprocket Support Bolts M8 X 1.25 X 24 18
Manual Shaft Detent Lever Nut M10 X 1.5 23
Line Pressure Test Plug 1/8 - 27 NPTF 12

Cooler Line Fitting into Case (97- early 99) 1/4-18 NPSF 28
Cooler Line Fitting into Case (mid 99- 03) Feed 3/8-18 NPSF
Return 1/4-18 NPSF
Cooler Line Fitting into Case ( 04+ ) 9/16-18 UNF

Accumulator Cover Bolts M6 X 1.0 X 28 106
2-1 Manual Servo Cover Bolts M8 X 1.25 X 25 17

Oil Pump Cover Retaining Bolt (97-mid 02) - 1 M6 X 1.0 X 20 70
Oil Pump Bolts - 9 M6 X 1.0 X 85 106
Oil Pump Bolts - 2 M6 X 1.0 X 95 11

Valve Body Bolts - 3 M6 X 1.0 X 65 106
Valve Body Bolts - 3 M6 X 1.0 X 60 106
Valve Body Bolts - 1 M6 X 1.0 X 30 106
Valve Body Bolts - 2 M6 X 1.0 X 45 106
Valve Body Bolts - 3 M6 X 1.0 X 55 106
Valve Body Bolts - 1 M6 X 1.0 X 95 106
Valve Body Bolts - 2 M6 X 1.0 X 20 106
Valve Body Bolts - 1 M6 X 1.0 X 85 106
Valve Body Bolts - 1 M8 X 1.25 X 90 18

Case Cover / Channel Plate Bolt - Torx - 1 M6 X 1.0 X 32 106
Case Cover / Channel Plate Bolt - 3 M6 X 1.0 X 30 106
Case Cover / Channel Plate Bolt - 3 M6 X 1.0 X 40 106
Case Cover / Channel Plate Bolt - 3 M8 X 1.25 X 50 18
Detent Lever Spring Bolt M6 X 1.0 X 16 106

 

Manufacturer Model Year Range Transmission

Buick Century 2000-2004 4T65E
Buick LaCrosse,Allure 2005-2008 4T65E. 4T65E-HD
Buick Lesabre 1998-2005 4T65E
Buick Lucerne w/3.8 V6 2006-2008 4T65E
Buick Park Avenue 1997-2004 4T65E, 4T65E-HD
Buick Regal 1997-2004 4T65E, 4T65E-HD
Buick Rendezvous 2002-2007 4T65E, 4T65E-AWD
Buick Riviera 1997-1999 4T65E, 4T65E-HD
Buick Terraza 2005-2007 4T65E, 4T65E-AWD

Chevrolet Impala 2000-2008 4T65E, 4T65E-HD
Chevrolet Lumina 2000-2001 4T65E
Chevrolet Malibu SS 2006-2007 4T65E
Chevrolet Monte Carlo 1998-2007 4T65E, 4T65E-HD
Chevrolet Uplander 2005-2008 4T65E, 4T65E-AWD
Chevrolet Venture 1999-2005 4T65E

Oldsmobile 88 Royal 1997-1999 4T65E, 4T65E-HD
Oldsmobile Aurora w/3.5 2001-2003 4T65E
Oldsmobile Intrigue 1998-2002 4T65E
Oldsmobile Silhouette 1999-2004 4T65E

Pontiac Aztec 2001-2005 4T65E, 4T65E-AWD
Pontiac Bonneville w/3.8 V61997-2005 4T65E, 4T65E-HD
Pontiac G6 w/3.9 V6 2006-2008 4T65E
Pontiac Grand Prix 1997-2008 4T65E, 4T65E-HD
Pontiac Montana 1999-2007 4T65E, 4T65E-AWD

Saturn Relay 2005-2007 4T65E, 4T65E-AWD

Volvo S80 1999-2002 4T65EV, 4T65EV/GT
Volvo XC90 2003-2005 4T65EV, 4T65EV/GT

 

i just read your article about the 4t65e-transaxle,i have a 2004 monte ss supercharged/4t65e-hd trans i always thought the diff. ratio was 2.93,and the standard 4t65e na cars got the 3.29 diff. your article states the supercharged cars have a 3.29 diff, and a overall overdrive ratio of 2.93. doe's GM list the overdrive ratio in there vehicle's spec's,or the actual diff. ratio? all of a sudden i'm confused, any help clarifying this would be greatly appreciated, Thanks for your time

 

I found the info and wanted to supply a common source for the info.
I hope that someone else on here will be able to help answer your question.

-Good Luck

 

I'm glad I stumbled upon this post; I had the exact same question.

I have a 2005 Monte (super charged / SS) it has the 4T65E-HD transmission.

According to the new-cars article: 2005 Chevrolet Monte Carlo - Specs, Data "Final drive ratio LA1: 2.86:1 ; L36: 3.29:1 ; L67: 2.93:1"

As far as I know, I have an L67, so that would mean I'm 2.93:1 ... However, I just got an HP scanner & downloaded my stock PCM file. Looking in the "Gear / Tire Calc section; the calculated gear is "3.29" ???

 

Now that's what I need to know I have a 2004 3.8 but not supercharger but the transmission is a 3.29 FR9 4T65E

 

Here's an excerpt from the OP's post that explains this.

So going off this, I'm guessing the N/A 3800s that have a 3.29 final driver ratio have a 35 Drive/35 Driven sprocket combination with the 3.29 diff.

Hopefully that helps y'all with questions about gear ratios.

 

If you have a 2004 Monte SS that is NOT supercharged, you have the L36 that will have a 3.29:1; If you have a standard LS Monte with the 3.4L engine, then 2.86:1 is the number you are looking for...

 

Does anyone know why we have this transmission instead of the 4T-80E? I have a friend with a 99 Aurora (as in, FWD V8) and it;s performed flawlessly for her....

 

I'm new here and have a question. I hope this is the right place for it. I've got the chance to get an 04 monte ss with the L36 engine an fr9 (3.29) ratio. The trans is slipping badly in it. I already have a good trans from an 04 grand prix with the f83 (3.05) ratio. My question is, could I use my grand prix trans by simply changing the sprockets and chain to to get the 3.29 ratio? Or what else would I need to do?