picked up a 97 mark viii parts car - odometer not working no forward gears

jruppert

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Alright, so i picked up a 97 Mark VIII and it was listed as a parts car. Got it for $400. I believe it has 135,000 miles.

Anyway, the guy said the tranny was junk. I knew this going into possibly buying. What made me skeptical was that he said the transmissions that they put in these were not very good and that the aod was a better tranny. So... I kinda figured he didnt know what he was talking about. I had my suspicion on the fact that it could be a bad range sensor switch. So I took my chances. I went to look at it and noticed the odometer not working. It just shows dashes. It also has an ABS light. I hooked up my actron and got a code for Transmission Range Sensor circuit low. That made me feel better about the tranny. I think its possible that I may have a working transmission. But it doesnt explain the dashes on odometer. I did not see any codes for ABS. Thought that was odd... So car, the engine sounds pretty good. It has the chrome octostars.

So what do you guys think?
 
First I'd calibrate the mlps to see if that fixes the tranny issue, it might correct the odo issue too.

Mlps
Vss
Ecm

are my guesses.

Since you have no forward gears it would be kinda difficult to see if the speedometer is working. Start at the mlps and see what happens.
 
I had a 97 a while back with dashes in the odometer. It was the ABS module. When you started it, it would flash the miles then go to dashes. It did not rack up miles. It was always the same number. I think you did good for $400. Best of luck with it.
 
I bought this with the intent of using engine and transmission for a cobra kit car that i am building. Just curious how much the engine is worth alone? If I were to sell, I would not be able to ship.
 
I bought this with the intent of using engine and transmission for a cobra kit car that i am building. Just curious how much the engine is worth alone? If I were to sell, I would not be able to ship.


You should be able to get your money back by selling the motor, not much more.
 
I got underneath to take a look at the switch. I noticed it off a little bit. I put the car in neutral and lined up the marks. To make things easier I took the rod that connects to the arm off. This allowed me to line up. However, after I lined it up the rod was not lined up to the bracket or arm. It was off slightly. Not sure what to make of it. I still had no forward gears. Shifter does appear to be off a little.
 
I decided to bite the bullet and buy a new MLPS. I placed the car in neutral and lined up the marks. Still has no foward gears. I was really hoping to see this fix it. It even had a code for transmission range sensor low circuit. Noticed that after I had it connected that the shifter inside was off a bit. I even had issues trying to start in P. I had to run gear selected down to 1 and back up to P to start. Otherwise I needed to start in N.
 
Usually if it is electrical you will have second and reverse, just reverse is likely mechanical.
 
i concur.
sounds like you will have a very crispy forward clutch pack.
rebuild time.
building an AOD is fairly straightforward, and the 4R70W is essentially the same.
if you are handy with some tools you should try rebuilding it yourself.

worst case you just pick up a used trans from copart or something if you get in over your head.
 
Thanks for the suggestions. I keep hearing people say that the +03 is a better unit than what we have. Is there much needed to upgrade? From what I understand, the valve body was improved. Anything else? If any changes are made, would it still play with the factory computer?
 
Thanks for the suggestions. I keep hearing people say that the +03 is a better unit than what we have. Is there much needed to upgrade? From what I understand, the valve body was improved. Anything else? If any changes are made, would it still play with the factory computer?

I'm fairly sure we can't use 4R70Ws past 2003 because they no longer have the location for the speed sensor that our cars require. You're thinking of the improved 4R70W that came with the '98 Mark VIII.
 
Even newer ones are a compromise. PERSONALLY a 98 Mark VIII transmission would be my choice. LATE 2000/2001 to 2002/2003 they removed the stiffener below the 2/3 accumulator piston and you frequently see it causing issues. You can get a thicker plate, or add a stiffener, and the JMod fixes some issues with the newer VB in an older car (like possible slow shifts).

03 is questionable if it will have the teeth on the output shaft, so you have to check that out. Most 04 and newer the OSS count is completely different and requires a speedcal like device, and you don't have the VSS.

Hopefully the transmission still has the tag on it, for the engineering number:
98 is F8xx-7000
99 is XWxx-7000
2000 is YWxx-7000
2001 is 1Wxx-7000
2002 is 2Wxx-7000
ETC

An example of Crown Vic engineering and model numbers: http://www.idmsvcs.com/2vmod/tranny/modelnumbers/crownvic/index.html

labelledtranscase02.jpg
 
i tell you what though, i ran my 93 to 170k on the "weak" unimproved trans with my foot flat to the floor around half the time.
then had it rebuilt and JMOD'd, and have put another 35k on it with no hiccups at all.

the newer transmissions are better, but the older transmissions are not so compromised that they are unusable.

i wouldn't throw 600 hp at an old trans without work either, but stock power is no big deal.
and i do know someone who threw 600 hp at a JMOD'd 98 trans as well. he was in the 10s.
 
At stock power I really don't think there's a real performance/life difference between a J-Modded '97 and a J-Modded '98.
 
The mechanical diode is a huge improvement in the 98+, but the same snap ring issue is present in both. I have the feeling I broke the roller clutch in my 97 Cougar. That is with a simple PI intake swap, 91 octane tune, and SLIGHTLY bumped shift points (and the JMod). Also I realize they are easy to replace, but I found in both my 97 4r70w's the old style accumulator pistons and trashed bores.

I guess I would pick the 00 transmission in my 00 Grand Marquis as the ideal one, older style OD circuit and plate, mechanical diode, better frictions.
 
I appreciate the help on this. It looks like I will look for a 98 instead of monkeying around with this 97.
 

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