Saturn S-Series question

[dodgeshadowchik]

Well, my sister's transmission (automatic) went out the other day in her 2001 Saturn SL. It's a 1.9L SOHC. Now her baby daddy's 1995 Saturn SL has a good transmission. I read online that they use the same trans form 95-01 (TAAT); but also read that 95-97 and 98-01 used different gear ratios and thus the computer will wig out and throw the car back into limp mode. Does anyone know if this is indeed true or not? I'm probably sure the 95's electronics are different than the 01's... so I don't think an ECU/TCU swap would work, either?

His car needs an exhaust, window, head gasket, and some other things... so it would be ideal if we could just sacrifice his car to fix the other.

It's kinda funny because right now there are 2 maroon Saturns parked in front of the house; broken.

[zin]

Saturns use another computer to run the transmission, I'm pretty sure you could swap the trans and computer and be fine.

Mike[COLOR="Silver"]

Edit:

I'm pretty sure the solenoids etc that run the trans are the same for these years, so I'd just install the trans and try running it on the existing computer. IIRC, years ago I was talking to some Saturn engineers who were planning to run the one lap of America and wanted to know about adding nitrous, that's where I learned that the auto cars basically use two ECUs, one that runs the engine, and the other that controls the trans. The latter models used adaptive technology to supposedly adapt to your driving style..., personally I preferred the older set-up, which had an economy/power setting... I still have the manuals for my wife's 98 SL2, so I can look-up and possibly scan info from them if you think it will help... Just let me know.

BTW, since the computer should be getting it's speed info from the trans, and the trans is calibrated for the gears it has, it shouldn't freak anything out.

Mike

[dodgeshadowchik]

Thank you! But is 2001 new enough where these modules were vin-programmed? That might be an issue if the 01 is. Any info would be appreciated since she really doesn't have a ton of money to work with.. Trying to save her some by frankenstein-ing cars. LOL! I'd love to see what the manual states if thats not a big deal. Sucks since I really don't know much about these cars at all.

[black86glhs]

MB, did it bust the case or is it just not working correctly?

[dodgeshadowchik]

Slipping, erratic hard shifts, ect. It'll default to limp mode now I noticed. It had the Pressure control solenoid(s) replaced last year for hard shifting. My dad took it back to the trans shop that did the work last August and said it needs a trans now. He went and picked it up... which kinda irked me because I would've liked to find out what codes were stored in the TCU. They said it had quite a few (naturally... based off of how it was acting) But certain ones will point to internal failures vs. electronic failures.

[zin]

Thank you! But is 2001 new enough where these modules were vin-programmed? That might be an issue if the 01 is. Any info would be appreciated since she really doesn't have a ton of money to work with.. Trying to save her some by frankenstein-ing cars. LOL! I'd love to see what the manual states if thats not a big deal. Sucks since I really don't know much about these cars at all.

The manuals are huge, so is there a particular part you'd like to see? Wiring maybe? Let me know and I'll see what I can do.

I can't say for sure about the vin programing, but I wouldn't expect the trans control portion to be keyed like the ECU, seems redundant.

Mike

[black86glhs]

Here is the deal. They are known for the 23mm nut on the input shaft and 30mm nut on the output shaft coming loose. They cause all kinds of issues, especially reverse and 2nd gear. They aren't that hard to fix and are easier to work on than a DSM or TM.

[88_pacifica]

The TCM/PCM(Powertrain Control Module) are external and the TCM is usually mounted on the top of the case IIRC. The internal controls(solenoids) should be the same from any of those years, however the gearing/shift points may be different from one to the next. IIRC the TCM's can be switched relatively easily and you 'should' be able to swap those over.

Early 90's models are similar to the later ones as shown here since the electronic controls were just being introduced. >> http://www.saturnwiki.net/index.php/TCM

[dodgeshadowchik]

Thanks again for the info everyone! I'll have to look into those bolts!

As far as some manual things, yeah the wiring would be great and perhaps the part about pulling the trans from the car. See what kind of mess we are getting into.

---------- Post added at 09:08 AM ---------- Previous post was at 09:05 AM ----------

The TCM/PCM(Powertrain Control Module) are external and the TCM is usually mounted on the top of the case IIRC. The internal controls(solenoids) should be the same from any of those years, however the gearing/shift points may be different from one to the next. IIRC the TCM's can be switched relatively easily and you 'should' be able to swap those over.

Early 90's models are similar to the later ones as shown here since the electronic controls were just being introduced. >> http://www.saturnwiki.net/index.php/TCM

Yea, that's the issue that seems to create the problem.. the fact that the shift points/ratios are different.

[88_pacifica]

Yea, that's the issue that seems to create the problem.. the fact that the shift points/ratios are different.

It should be pretty much plug and play for the most part. The big issue is that module, but I would call a trans shop in a smaller, rural town somewhere and see what they say and what they would recommend. Nothing says you need local assistance from busy people. I have found that a long distance phone call to a rural midwestern town in the middle of nowhere gets you connected to an older, more friendly person that is more than willing to give you his two cents. If you appear pretty knowledgeable on the phone, often times they will give you great general information. Don't expect any more than that though as they do seem to be talkers and just ramble on and on...

[Big_P]

You have a sister? Pics?