It'* possible, and I refuse to 'downgrade' my car lol. They screwed up, they're paying for it. I was thinking the same thing, and I hope they don't try to throw that at me, because that'* a good way to anger me lol. It popped in my mind for a split second before I realized I'm not settling to allow them to fix their mistake for cheaper.

Yes I realize that and I don't blame you.
I was looking for information about what could be done to swap a different trans into, I don't know, let'* say my car. I don't really give a flip about the performance aspect of it, I am more concerned with mileage and reliability. When the time comes for a transmission swap I will get my neighborhood salvage yard to swap it for me and I was just wondering if the PCM is all that would be required to make a different ratio work.

According to my recent research and knowledge, the PCM should be the only thing 'stopping' you from changing gear ratios. I'm more for the performance aspect of things.

Word.

I have a Pontiac 400 for that.
My other cars

Does the different gear ratio in the tranny affect your speedo/odometer at all? Just curious

Possibly.

The speed sensor takes its reading from the differential. The diff has a "tone wheel" on it, and the sensor counts each time a "finger" passes by it. If the diff in the car now has the same number of fingers on the tone ring as the original (and I suspect it does), the speed will be calculated correctly. Back in the old days, when rear-drive was king, speed was taken from the output shaft of the transmission. Changing gear ratios inside the transmission did not affect the speedometer readings. Changiing the final drive ratio, however, would throw it off, as well as going to a different tire size.

The problem lies in the shift tables. Currently, his pcm is set up for 3.06. Meaning at a certain speed, certain TPS postion, and any other input, the trans needs to make the shift to the next higher or lower gear. The current trans, however, has a different schedule to follow, but can't do it well enough to do its job properly because it is being given wrong information.

It'* got "Special Ed" syndrome, in other words.

My SSEi suffers from this too. It works well enough, but not to its full potential (my ratio changed from 2.97 to 2.93 when I rebuilt the trans. Not enough to harm it, but enough to notice a difference in shift behavior)

The speedometer will always be correct as long as the tire diameter is correct. The speed is taken from the outside (drive the wheels side) of the diff.

So I called the transmission place today.

They took my paperwork and couldn't understand why the transmission that was in there, was even functioning as well as it was.

They called the salvage yard that provided the transmission and they said somehow their inventory got screwed up. They were also impressed with all the documentation I provided. So they're in the process of finding me a new low mileage 3.06 unit.

They were having a hard time figuring out where I got all the information, so I explained that there was actually a forum out there dedicated to these cars with thousands of members. That cleared things up a little bit lol.

I enjoyed hearing such a positive response. They're unsure when they'll be receiving the replacement unit, and offered to let me have my car back until then. I think I may... as the 98 Plymouth Grand Voyager 'Expresso' is a bit of a gas guzzler.

Excellent.




Call of the hounds.