1988 Grand Marquis Transmission?

I had one of the early AOD transmissions in '84 and have had several automatics. Your transmission is fine, just do the fluid & filter things. I have never had a car with an automatic that would hold on much of a hill. They aren't really designed to. That is a great car, by the way. My parents have about 40k on theirs right now. I drove it on a few family vacations with them - never got a cramp or ache from any length of trip. Comfy as all getout, too.

Paul

Sharon,

Your vehicle has an aod transmission. The bands are self adjusting.

To answer your question regarding the hill. There is no truth to this type of test. The only good this test would be good for is if your accelerated , the rpm's went up but you didn't move. The trans would obviously be slipping. The reason a vehicle would stay on drift backward is the stall speed of the torque converter. A stall speed is determined during the manufacturing process by changing the pitch of the vanes inside the torque converter. The reason for different stall speeds is for different applications (towing, racing, highway driving etc.).

One thing you want to take into consideration. If the fluid has never been changes and you have over 70,000 miles you could be asking for trouble by changing it. The dirt, debris, sludge that builds up behind seals (rubber components) can was away due to the detergent in the new oil. If this happens you may experience slippage because of the older hardened rubber seals.

Hope this helps.

John

No, not really. Some truth in what you were taught. When the engine is at idle it is making it's lowest amount of torque. So a hill that is at a steep angle, or a vehicle that is heavy (like the Grand Marquis ) will easily over come what ever torque the engine is producing and roll in the direction of the incline. A normal condition. It's not really "slippage", just the fact that the turbine in side of the torque converter does not have enough fluid thrown at it to hold the car still.

Being that the transmission is an AOD there are no bands to adjust. This friend who is supposed to be a good mechanic should also know that you can adjust all the bands you want, it will not fix a condition you describe.

Thomas,

I thought the term self-adjusting was the easiest way to explain that there were no adjustments (short of changing the servo piston) on the AOD transmission. I'm surprised you would pick apart my description like that. Especially after my compliment to you just two days ago with the aerostar overheating concern. I would have never thought to pick apart your explanation of the torque converters function, however I'll just throw in a little shot for fair play.

Thomas, the torque converter impeller pumps fluid to the turbine which then is redirected by the stator. By no means is it thrown at anything. The amount of torque is regulated by the angle of the blades on the turbine.

God forbid I didn't articulate my answer perfectly. But I guess we all make mistakes. No response needed.

Good day,

John

accelerated ,

Thomas,

If you didn't want a pissing contest you would have left it alone from the start. I think you got exactly what you were looking for. My example of the torque converters operation is just fine and as far as replacing something to adjust the band, it is possible and parts are available to change the piston rod length, however it's not likely that a tech would bother with this operation unless there was a problem. I simply added the information for clarity.

I believe we both respond to posts with quality answers. I would hope you agree. I certainly have respect for your knowledge. Lets move on from here and leave this one in the past. I joined this group to try and help others, not to debate terms I or others use to try and simplify an explanation for easier interpretation.

John

That statement back too you. Remember it take two, you even said you "owed me one".

Yes it was a good oversimplified example, but left out some very important information that made it not so correct.

Now you have it correct, it is the rod, not the piston you change. If the band is burned and is the only friction material in the transmission that is, don't you think there is a problem that needs too be explored as too why it burned?

I simply added the information

I do not care about spelling or grammar mistakes, but when information on how something works or how to diagnose or any thing along that path, I do expect it to be correct. If I see something that may mislead, I do correct, just as I have been. Something you are alluding too in you last statement.

Thomas,

It only takes one to start a debate, it takes two to continue it.

I'm sorry but I missed the election to vote you in as Newsgroup Master. There was nothing misleading about my statement and I'm sure Sharon received the information she seeked and understood it just fine.

Obviously you have no intention of leaving this one in the past which proves that you are and were looking for a pissing contest.

Enjoyed the dance,

John

Which you clearly did continue.

I missed the vote as well! I am? Gee that is great? Man, I didn't even know there was an election.

You then should not have started the "however I'll just throw in a little shot for fair play." You could have just said to your self, yea, not the greatest choice of words.........mirror, mirror on the wall, look at it. Don't sit there and point fingers.

Thomas,

Ok, here we go again. After numerous attempts and several kind words you are obviously unable to clear your mind and move ahead so I will be the bigger man and do it for us.

Dancing with you reminded me of something my grandfather once told me, "you can't reason with a fool".

Sincerely,

John

Bigger man J.? LOL!

Just wanted to follow up on my original question so that anyone reading the arichives would know what I found out. I took it to my mechanic in NY and he said (as Thomas also said), that this was normal behavior for this car. He changed out the fluid, put in a conditioner, and changed out the filter (at my request). When he pulled the pan he said that the fluid looked relatively clean, so he is assuming that the previous owner did maintain it properly. In any even, I drove it across country and never had a problem until I got here and that wasn't with the transmission at all. I have posted my other problem to the Ford group, but didn't get any help. So, I will post it here in another post.

I just wanted to say that although my original post seemed create some ruffled feathers; I did feel comfortable with the actions of the transmission once Thomas explained what 'normal' was to me. Thanks and take care, Sharon