wrong tranny installed?

[regalfriend]

wrong tranny installed? (Post #1)

i have a 1997 1/2 regal gs 3800 series 2 supercharged motor...milage 112000../ tranny was slipping in first gear...brought the car to buick(have aftermarket warranty)...buick sent car to aamco...picked up car from aamco and have had nothing but trouble...at first tranny had real soft shift, brought it back to aamco they said valve body gasket was no good and replaced...after a few days had more problems...no 4th gear or lockup and car was hanging in 2nd gear around town...went back to aamco and was told there was low voltage to tranny from engine which affected shift...picked up car again to have the same problem but worse, service engine soon light came on, had the mechanic check the code and was told it was o2 sensor.....i have not brought it back yet, and am afraid they will cause more damage to my car...all documentation i recieved from aamco suggested my tranny is a 4t65e i know my tranny is a 4t65e-hd, used for L67 motor...can anyone tell me the difference between the 4t65e and the 4t65e-hd transmission? i heard 4t65e-hd has a longer valve body shaft, is there any difference w/ the gears or clutches or torque converter?

[BNaylor]

Originally Posted by regalfriend

wrong tranny installed? (Post #1)

i have a 1997 1/2 regal gs 3800 series 2 supercharged motor...milage 112000../ tranny was slipping in first gear...brought the car to buick(have aftermarket warranty)...buick sent car to aamco...picked up car from aamco and have had nothing but trouble...at first tranny had real soft shift, brought it back to aamco they said valve body gasket was no good and replaced...after a few days had more problems...no 4th gear or lockup and car was hanging in 2nd gear around town...went back to aamco and was told there was low voltage to tranny from engine which affected shift...picked up car again to have the same problem but worse, service engine soon light came on, had the mechanic check the code and was told it was o2 sensor.....i have not brought it back yet, and am afraid they will cause more damage to my car...all documentation i recieved from aamco suggested my tranny is a 4t65e i know my tranny is a 4t65e-hd, used for L67 motor...can anyone tell me the difference between the 4t65e and the 4t65e-hd transmission? i heard 4t65e-hd has a longer valve body shaft, is there any difference w/ the gears or clutches or torque converter?

The 1997 and up Regal GS has the RPO MN7 4T65E-HD tranny. The 1997 and up Regal LS with the NA 3800 Series II engine have RPO M13 (1997-98) and M15 (1998) and around 1999 it was changed to RPO MN3. There are variances.

On the 4T65E-HD versus 4T65E the torque convertors are different via the flex plate. The transaxle half shafts are different. The splines are bigger. The gear ratios are different and the output gears and bearings are beefier. The clutches are the same. In the 1997 M13/M15 models there may be differences in the solenoids such as the PCS, TCC PWM and up shift. The rule of thumb is always use the torque convertor from the L67 RPO MN7 on the Regal GS.

The ECU/PCM for L67 RPO MN7 is programmed differently for different shift points and higher line pressure, etc.