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1995/1997 AWD transmission interchange

7K views 7 replies 6 participants last post by  Phantom 
#1 ·
Will a transmission from a 1997 AWD Astro with 4.3 vortec engine fit my 1995 AWD Astro with the pre-vortec six cylinder? What kind of job is it to swap transmissions?
 
#2 ·
I'm not sure about the interchangeability, one of the guys or gals who do transmissions a lot may know. A transmission swap can be an easy job if you know what tools you need and have all the equipment but it gets harder with an AWD/4x4 Setup, that's why transmission shops typically charge 500-700$ if it's an AWD, it's hard I'm in the same boat.
 
#3 ·
Your '95 Transmission can only be replaced with a '95 Transmission from what I have read on this board in the past. Probably better off just having it rebuilt. Thats why people tend to stay away from '95 year Vans cause of some of the parts being specific to just that year(not that '95 Vans are bad :D ).
 
#4 ·
95' seems like a changeover year for lot's of automakers. Like Blazers and Astros parts from that year are not interchangeable, Ford windstar. Most likely because it was a year that a lot new models and new designs came out :2: . Nothing against 95s just the convenience of getting parts for them.
 
#5 ·
Ya its not OBD1 or OBD2.......its like OBD1.5 or something goofy. A '95 Blazer or Fullsize pickup tranny might work, but someone else would know for sure. As far as I know though a 1995 transmission is a one year deal.
 
#6 ·
As stated by others, 95 is a one year deal. If you have questions as to parts interchangability, you can always look at one part for your van, and then look at the same part for the van the year before and the year after to see if the part number is the same. If it is, then you know your range.

1995 was the year ALL manufacturers started the switch to OBD2. My 95 Toyota Pickup is that way too. I can scan codes with my obd2 scanner, but I can't clear them.

1996+ are all OBD2, 1995 OBD 1.5 and prior are OBD1 into the mid eighties I believe.

Part of the issue with the transmission is TCC lock up and how it's dealt with.
 
#7 ·
1995 is a transitional year for obd1 (also 1.5) and obd2 but the transmission should not only bolt up but function the same. The only exception would be if your original 95 4l60e did NOT have PWM. In that case I don't think it would work.
 
#8 ·
Just to clear some things up , OBD1.5 is basically OBD1 with a few additions like the 16 pin diagnostic connector , and pinned differently , , but with the correct OBD1.5 adapter it is scanned using OBD1 software and tuned with OBD1 software , Some 94 cars had OBD2 , but not many , only a handful , more in 95 , and across the board universally in 96 .

here is an excerpt from a 4L60E swap guide :

To put a '95 4L60E into a '94 car: No mechanical mods required. TCC Mod (stake the TCC valve)
must be performed. The trans will operate normally without TCC Mod 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. TCC Mod must be performed. The trans will operate
normally without TCC Mod but TCC lockup will not work, so highway and cruising gas mileage will suffer
and more heat will be produced in the transmission.

TCC Mod (method 1):
An additional wire must be run from the PCM connector D pin 6 to pin "U" on the trans harness for the
TCC to work. Also, the PCM must be reprogra ed with '95 transmission base code. In my opinion this
is more work than its worth due to the amount of labor involved in properly routing an additional wire
into the powertrain wiring harness.

TCC Mod (method 2):
Leave the 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, and stake it into place. That'll lock
keep the valve acted on by the PWM in the full-open position and it'll function like a '94 style lockup. No
PCM reprogra ing required. You may have to swap the '94 internal harness into '95-'96 transmission,
but I'm not sure. I reco end not swapping harnesses if you don't have to, because they will most
likely be brittle and are tricky to remove from the case without damaging the lugs on the connector.

a 97 will swap into a 96 no problem ,,,

installing in a 95 would need some wiring mods and making it work with the 95 NSS
I have not done the swap , but seems some people have ,, but it is uncommon as most people stick to the assured method of using the same year of trans to make it simple
 
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