anybody know about auto transmissions?

speadfreak

New Member
Oct 13, 2005
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it's not a mustang, it's a 97 mark viii. I've been told the transmissions are the same as the 98 and newer mustang GT trans. Anyway, the trans takes a long time to shift out of 1st gear and gets worse the harder I accelerate. I took it to a local transmission shop and was told that there were no codes stored in the computer. They said that they could not find anything wrong with it. It's not bad, or in anyway undriveable.......it's just no quite right. Anyone have any ideas?
 
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If you are unsure about the mileage, don't do that flush. I've seen some high mileage cars that had never had the trany fluid changed, and after a flush, they never moved again.

Last summer, I ended up rebuilding an AODE in a 93 Mark 8. It was slipping, and hanging in first for a while. The torque converter was completely shot too. After a new O/D band, some clutch plates and steels, and a new TC, it shifted like brand new.

The trans in that 97 is a newer version, and a fair bit tougher. It's still an AODe, but in 4r70w flavor. It's not of the 99+ design however. If you can manually shift the car with no problem, and its holding power is all there, I would blame your shift problem on a crappy solenoid, or a damaged accumulator spring. The spring in the one I worked on was in like 10 pieces. You have to drop the pan to get to those, so if you do try, I reccomend using Mercon V fluid as opposed to Dexron 3 Mercon to refill it. There are a few more things that it could be, but I have to go rescue a car from a flatbed right now.
 
I got real bad news for you...

Your Mark VIII has the "fail prone" intermediate one way roller clutch and by the sounds of things, yours is finished. Not shifting out of first is a tell-tale sign of that. You are looking at either a rebuild or to get a newer 4R70W. You will need to repin a harness on your car if you intend to go with 99 or newer 4R70W. If you decide to rebuild, build the transmission to a minimum of 98 specs and use the Mechanical Diode one way roller clutch.

If you want to confirm my suspicion, drain your transmission and drop the pan. If there is metal shavings in the pan, your one way roller clutch failed.
 
The car still shifts out of first........it just doesn't do it until like 4k just accelerating normal. If I hammer on it, it doesn't shift until like 6200. It makes no difference if I try to shift it manually. But.....if I let off the throttle slightly, when it seems like it is hanging up, it will shift the second I lift.The fluid is a little on the orange side...not quite red (just looks like it needs changed) and it does not smell burnt at all. I was going to change the 1-2 acumulator this weekend. It's easy to do and less than $100 for all the parts. I have read like a million different articles saying that they are prone to failure and there was a TSB about it. I bought this car off of my neibor extremely cheap, because he is hurting for money. The mark VIII is really not "my thing", but it has cool body lines and a very cool motor in it. It has a leaking front airbag so he stopped driving it. He's a pretty honest guy, and swears up and down that there was nothing weird with the tranny when he parked it 3 months ago.
markviii0003.JPG
 
Automatic transmissions , well a lot of them have like a safty over ride because the trans is not made to shift at 6200 thats why when u let off of it ,it shifts, thats why they make shift kits
 
Mustang180 said:
Automatic transmissions , well a lot of them have like a safty over ride because the trans is not made to shift at 6200 thats why when u let off of it ,it shifts, thats why they make shift kits

okay.....well, as I said, it does the same thing under normal driving at like 4000rpms. I'm pretty sure the trans is made to hold up to a 4000rpm 1-2 shift. Maybe I am misunderstanding you.
 
speadfreak said:
The car still shifts out of first........it just doesn't do it until like 4k just accelerating normal. If I hammer on it, it doesn't shift until like 6200. It makes no difference if I try to shift it manually. But.....if I let off the throttle slightly, when it seems like it is hanging up, it will shift the second I lift.The fluid is a little on the orange side...not quite red (just looks like it needs changed) and it does not smell burnt at all. I was going to change the 1-2 acumulator this weekend. It's easy to do and less than $100 for all the parts. I have read like a million different articles saying that they are prone to failure and there was a TSB about it. I bought this car off of my neibor extremely cheap, because he is hurting for money. The mark VIII is really not "my thing", but it has cool body lines and a very cool motor in it. It has a leaking front airbag so he stopped driving it. He's a pretty honest guy, and swears up and down that there was nothing weird with the tranny when he parked it 3 months ago.
markviii0003.JPG

I know your car is shifting into 2nd, the hesitation or hang or whatever you want to call it into 2nd is a sign that the Intermediate OWC has failed. You may want to read this article, it was written by the guy who designed the transmission in your car. There may be a cheap fix to the issue you are having. I know my TBird did what you are describing and it was the OWC that went on me.
 
How hard is it to fix the OWC problem.....does the tranny need to be dropped? Sounds like it's either that or the 1-2 accumulator. Thanks, that link was very helpful.
 
speadfreak said:
How hard is it to fix the OWC problem.....does the tranny need to be dropped? Sounds like it's either that or the 1-2 accumulator. Thanks, that link was very helpful.

Well, if it is either one, you need to drop the transmission pan. When you do, if there is metal shavings in the bottom of it, it is the OWC and to repair that, is a complete rebuild or replacement with another transmission. If there is no metal shavings, it is quite possible it is just the accumulator.