A604 ID help needed

[TopDollar69]

Guys,

I'm looking to get a different transmission in my 1990 Imperial. The one I have in the car now has really bad bump shift and converter shutter. I'm wondering what years will work, and if any of them are better than others. Thanks for any help you can provide, as I don't know much about the 4 speed autos. I do have the most up to date TCM installed in the car, and it did help quite a bit with the converter shutter, but it still has some.

[pauly_no_van]

Maybe a new converter and a cooling line filter would fix it?
If the software update helped but didnt fix, then next part i'd try is shift solenoid.
Plus, if the TCM is not synced somehow with the ECU, there can be problems(I have read).
I have a 96 a604 in my garage with 10k on a complete rebuild i would let go cheap to somebody here.

paul

[Vigo]

The main thing you need to look out for is obvious differences in the case. If you look at the transmission in your car now, you'll see it has a couple of electrical components on the front corner of the case. I think it's a neutral safety switch and a range sensor but dont quote me on that. Anywho, at some point they moved those functions into/onto the valve body and solenoid pack and later cases do not even have holes for those two components. I think the cutoff date is around ~94-95. So you cant really get a much newer trans in there. Any 90-95 trans is a total crapshoot by now unless it's been recently rebuilt and you can drive before buying.

I would look into fixing what you have.

[pauly_no_van]

The main thing you need to look out for is obvious differences in the case. If you look at the transmission in your car now, you'll see it has a couple of electrical components on the front corner of the case. I think it's a neutral safety switch and a range sensor but dont quote me on that. Anywho, at some point they moved those functions into/onto the valve body and solenoid pack and later cases do not even have holes for those two components. I think the cutoff date is around ~94-95. So you cant really get a much newer trans in there. Any 90-95 trans is a total crapshoot by now unless it's been recently rebuilt and you can drive before buying.

I would look into fixing what you have.

hmm, Im going to scrap this a604 I have I think, sell the good parts...... Thing is new inside completely, but people are so burned-out on them breaking nobody believes it is good.
Chrysler did an excellent job engineering these vehicles to be worthless after 100k or so.
I'm glad I got rid of that van (96 grand caravan) It broke everywhere like a grenade in slow motion.
It was nothing but a pain in the A$$ whole time I had it.

[Vigo]

My parents had a 97 3.3 GC from 30k to 245k. I opened up the trans around 205k because it was starting to have issues when cold (typical aged-out seals). I think i found a worn planetary and replaced that, and i replaced the solenoid pack, everything else was just seals and clutches (did the clutches just because i was already in there) and it still worked fine when they traded it in on cash for clunkers. Hardly anything ever broke on that van. Before that they had an 89 3.0/604 (first year for 604) that they drove up to 180k before the transmission started slipping and they got tired of the valve guide smoke. So that one lasted a pretty long time. My 604 from my first 3.3 dynasty i bought w/64k back in 2001 still lives on in my cousin's 3.8 94 GC, trans now has ~130k and is 20 years old this year, still works fine. The 604 in my 3.0/604 dynasty i had was still working fine @ ~170k when i took it out for a 5spd swap. It's sitting in my storage shed. I actually put a ~253k mile 3.8/604 drivetrain from another 94 GC into my 90 dynasty so the 604 in there MAY have 250k on it. It works fine.

When i worked at a transmission shop the majority of 604s that came in were taxis, and the majority of them died from heat damage (which is why everyone says put a cooler on your 604 and it will live a lot longer). Other than the taxis, i actually saw more 3spds come in with problems than 4spds. When the 4spds came in with driveability issues it was almost always a sensor or a solenoid pack whereas the 3spds you actually had to open up.

[pauly_no_van]

My parents had a 97 3.3 GC from 30k to 245k. I opened up the trans around 205k because it was starting to have issues when cold (typical aged-out seals). I think i found a worn planetary and replaced that, and i replaced the solenoid pack, everything else was just seals and clutches (did the clutches just because i was already in there) and it still worked fine when they traded it in on cash for clunkers. Hardly anything ever broke on that van. Before that they had an 89 3.0/604 (first year for 604) that they drove up to 180k before the transmission started slipping and they got tired of the valve guide smoke. So that one lasted a pretty long time. My 604 from my first 3.3 dynasty i bought w/64k back in 2001 still lives on in my cousin's 3.8 94 GC, trans now has ~130k and is 20 years old this year, still works fine. The 604 in my 3.0/604 dynasty i had was still working fine @ ~170k when i took it out for a 5spd swap. It's sitting in my storage shed. I actually put a ~253k mile 3.8/604 drivetrain from another 94 GC into my 90 dynasty so the 604 in there MAY have 250k on it. It works fine.

When i worked at a transmission shop the majority of 604s that came in were taxis, and the majority of them died from heat damage (which is why everyone says put a cooler on your 604 and it will live a lot longer). Other than the taxis, i actually saw more 3spds come in with problems than 4spds. When the 4spds came in with driveability issues it was almost always a sensor or a solenoid pack whereas the 3spds you actually had to open up.

Karma then.