RWD 19xx-1984 DeVille and Fleetwood, 1985-1996 Fleetwood and Brougham ForumForum for discussions regarding the rear wheel drive Pre80s-1984 DeVille and Fleetwood, 1985-1996 Fleetwood/Brougham.
GM B and D-body 4L60E differences by year:
94: First year of electronic controls in the valvebody (versus the 93 4L60, which did not have this). The PCM controls line pressure (holding power and shift feel), 1-2, 2-3 and 3-4 shift points (rpm), and TCC lockup (timing and in the 95-up models, apply feel). Everything else is done mechanically/hydraulically.
95: Added a Pulse-Width Modulation Torque Converter Clutch (TCC) apply solenoid to control the feel of the TC clutch lockup (blamed for many 4L60E problems; TransGo HD2-C bypasses this, or you can stake the TCC apply valve in place). Also changed 3-2 downshift solenoid mid-year (see '96, below).
96: PWM TCC plus a different tailhousing design with new-style Vehicle Speed Sensor (VSS). Also changed the 3-2 downshift solenoid in mid-1995 from TBD to TBD. There was a new manual valve added along with a relief port over the manual valve on the valve body casting with this change. This solved the low/reverse clutch release problem and makes the TransGo manual valve mod unnecessary.
How to visually tell B and D-body transmissions apart by year:
'94: VSS on driver's side of tailshaft housing, and when you remove the torque converter, there is no "PWM" on the front surface of the pump. In the pan, only one solenoid on the front face (relative to the transmission in the car) of the valvebody.
'95: VSS on driver's side of tailshaft housing, and when you remove the torque converter, there is "PWM" in raised letters on the front surface of the pump. In the pan, there are two solenoids on the front face (relative to the transmission in the car) of the valvebody.
'96: VSS on passenger side of tailshaft housing, and when you remove the torque converter, there is "PWM" in raised letters on the front surface of the pump. In the pan, there are two solenoids on the front face (relative to the transmission in the car) of the valvebody.
9C1 Trans differences:
9C1 4L60Es come with a 1st gear lockout function that is a tab secured next to the shift linkage by the oil pan bolts. This can be removed by removing the two bolts and then reinstalling and torqueing them to 9ftlbs.
LT1 vs. L99 Trans differences:
4L60Es in L99 4.3L V8 cars come with a smaller servo than the LT1 5.7L V8 cars, which come with the cor-vette servo for more holding power on the 1-2 and 3-4 shifts. If an L99 4L60E is going behind an LT1 engine, the servo assembly should be swapped over before installed (easily accessible on the passenger-side of the case). TransGo also sells a vette servo that can be installed as part of their 4L60E HD-2C reprogramming kit. Also, the boost valve is smaller (again, Transgo fixes), and it is possible that some holes in the separator plate are smaller.
Cadillac Fleetwood V4P differences:
Cadillac spec'd the Fleetwood towing package (V4P) to tow up to 7000lbs. The transmission was setup from the factory to shift a bit firmer. If you swap one of these transmissions into your car, be careful how line pressure you add in via the PCM. Each vehicle and package generally had some small tweaks (L99 vs. LT1, truck vs. car), so be aware that the shift feel will probably not feel the same after a swap.
Can I use a 4L60E from a...?
Note: This info assumes you can swap or remove cooler line fittings, electronics modules, tailshaft housings, and shifter brackets yourself.
1. CK Truck or Fullsize Van: Any "K" case out of a '94-97 GM full-size 2WD pickup will work. 4WD transmissions have shorter tailshafts which cannot be swapped without disassembly. 4L60Es behind the 305 V8 and 4.3 V6 came with the smaller '..553' servo which should be replaced with an '..093' "corvette" servo. Other V6 versus V8 internal differences are unknown.
2. S10/Blazer (2WD V6 only): Probably. 4L60E was used '93 up to '96???. You will need to swap the servo assembly out of your b-body 4L60E (make sure to put a new blue o-ring on the servo cover when you do so). Other mounting, electrical and internal differences are unknown at this time.
3. F-body (Camaro-Firebird) LT1 4L60Es from '94-00 will fit. They also have the "corvette" servo. LS1 4L60Es from '98 up will bolt on but you must use the LS1 torque converter. Unknown as to whether the LS1 TC will bolt to an LT1 flexplate. V6 transmisssions have incompatible bellhousings and will not work.
4. Corvette 4L60Es from '94-96 are identical internally (and obviously have the "corvette" servo). The difference is the case. It will be impossible to bolt the exhaust hanger bracket to the case without modification to the vette case.
Can I use a 4L60 or 700R4? from a '91-93 Caprice or other vehicle?
Don't bother. You could, but it's not worth the effort. The internal rotating parts are basically identical but everything else is different. Sell it and get a 4L60E.
Caprice Transmissions from '8x-96:
198?-1990 - 700R4 (also 200-4R on some models)
1991-1993: 4L60
1994 - on : 4L60E
Year to Year B/D-body Swap Guide:
To put a 94 4L60E into a 95 car: Direct bolt-in; no mechanical or electrical changes required. The PCM must be reprogrammed with 94 transmission base code to avoid setting a silent code (Check Engine Light (CEL) does not illuminate, but code stored in memory). Trans will operate normally without reprogramming.
To put a 94 4L60E into a 96 car: The 96 tailshaft housing and VSS must be installed on the 94 4L60E before the trans can be bolted into the car. No other mechanical or electrical mods necessary. The PCM must be reprogrammed with 94 transmission base code to avoid setting a silent code (Check Engine Light (CEL) does not illuminate, but code stored in memory). Trans will operate normally without reprogramming.
To put a 95 4L60E into a 96 car: The 96 tailshaft housing and VSS must be installed on the 94 4L60E before the trans can be bolted into the car. Technically, the 3-2 downshift solenoid should be swapped also, but experience shows that it is not required.
To put a 95 4L60E into a 94 car: No mechanical mods required. Mod A must be performed. The trans will operate normally without Mod A but TCC lockup will not work, so highway and cruising gas mileage will suffer and more heat will be produced in the transmission.
To put a 96 4L60E into a 95 car: The 95 tailshaft housing and VSS must be installed on the 96 4L60E before the trans can be bolted into the car. Technically, the 3-2 downshift solenoid should be swapped also, but experience shows that it is not required. No other modifications are necessary.
To put a 96 4L60E into a 94 car: The 94 tailshaft housing and VSS must be installed on the 96 4L60E before the trans can be bolted into the car. Mod A must be performed. The trans will operate normally without Mod A but TCC lockup will not work, so highway and cruising gas mileage will suffer and more heat will be produced in the transmission.
Mod A (method 1):
An additional wire must be run from the PCM pin TBD to pin TBD on the trans harness for the TCC to work. Also, the PCM must be reprogrammed with 95 transmission base code.
Mod A (method 2):
Swap the 94 internal harness into '95-96 transmission, leave PWM solenoid unplugged but installed. On the valve directly to the right of the PWM solenoid push that valve all the way towards the outside of the valvebody , push it against the side of the valvebody and stake it into place. Thatll lock down your PWM function and itll function like a regular lockup. No PCM reprogramming required. Now with pics!
Awesome! I was trying to figure out what the diff in the 2WD truck trans to the trans we have.
So, wonder if a 4L65E or 4L70E will work (if 2WD)?
Note: If you install a TransGo HD2 in a 95-96 trans you have essentially made it a 94. It eliminates the TCC PWM solenoid operation. This is VERY important to long 4L60E life..... Case in point, my 94 has 248K on stock trans...... (ok V4P might have helped a little....) But 95-up got PWM and it hurt trans longevity.... HD2 fixes it and disables it....
thanks 96fleetwood, awesome info, not as scary as i feared, i will be pulling apart a clean 95, and a friend wants the tranny for his 94, didnt want to steer him wrong...
hey 96fleetwood, thank you for the informative response, is there a link that shows the way to make the 95 4l60e work in a 94, it says pics, was wondering so i could pass it along thanks
The key is to disable the PWM solenoid. Get a TransGo HD2 and you are set, or do the staking mod listed above. If you don't stake or "fix" the PWM solenoid, you will trash the trans in short order. The TransGo HD2 has a spring that forces the PWM valve in the 100% position to it is safe to use and the trans will act like a 94.
Grab a HD2, you won't regret it. Not the SK kit, the HD2 is a must. There is another kit out there that is very similar to the HD2, that one is fine too.
How does a PWM TCC solenoid cause early trans demise? Excess heat? Excess TCC wear and junk in the fluid? I can't imagine it's either of those. Must be something else.
I am about to pick up a 95 this evening. Does Tunercat have a means to essentially max out the TCC apply solenoid force? My Camaro was an M6 and my Caprice is an L05 so I have spent hardly any time looking at the 4L60-E tables.
The TCC would live in slip mode, yup, and it will overheat and trans the fluid.
I guess you could theoretically do it in TC, but only if TCC is wired up, the wiring on the TCC PWM solenoid is not present on a 94 car. I never complained about the TCC in my 94, but in my 00 SC Park Ave Ultra, (has a loose converter stock) I railed them to 100% and it was pretty annoying. I will firm them up, but Buick's stock TCC PWM apply is pretty seamless.
The key is to disable the PWM solenoid. Get a TransGo HD2 and you are set, or do the staking mod listed above. If you don't stake or "fix" the PWM solenoid, you will trash the trans in short order. The TransGo HD2 has a spring that forces the PWM valve in the 100% position to it is safe to use and the trans will act like a 94.
Grab a HD2, you won't regret it. Not the SK kit, the HD2 is a must. There is another kit out there that is very similar to the HD2, that one is fine too.
where can i order the transgo hd2 kit, about how much does it run??, is it user friendly install??thanks for your help
