wildrage

Hey guys:

I have a '99 v6 automatic, 130kand the car just started revving in drive for no reason last week. I got it home in 2nd gear (luckilly I was close). At first I thought it was the neutral saftey switch...I had a few of them blow out in lincolns that I have owned. I replaced it and the damn thing was actually rusted to the linkage...I thought I solved the problem.

But I didn't. It now looks like the problem is with OD. The car runs fine with OD off, but with OD on, it will neutral out after about 20 seconds of driving. For example, it will neutral out after driving at 35mph at a constant rate for a few blocks. Turning OD off fixes the problem.

The strange thing is, this all started happening at once. The transmission was working flawlessly and OD just gave out with no noises, prior slipping, etc.

So far I have:

- Changed Neutral Saftey Switch
- Checked fluid (it was nice and red, right level, and not burnt).

I plan on pulling the pan and changing the filter tommorow.

Any body have any ideas? Other then the OD band might be blown? Any ideas would help.


Thanks,


James

corvetteguy

My experience with the 89 GT is if the fluid
gets a little low problems will follow.

On my 97 F150 the trans fluid must be changes at 30K
and every 30K thereafter. When was your fluid changed?

The friction modifiers wear out and the trans slips. New Mercon V
will help in most early problems.

nyuk98gt

wildrage:

The OD band is the weakest link in the 4R70W transmission. If you haven't done it, zip over to TCCoA.com and read "Transmissions 101" in the Tech Articles/Transmissions section. There are 18 or so chapters and the author is a former Ford tranny engineer and, obviously, knows his stuff. There's a chapter on troubleshooting that you will find helpful.

Since the problem is with OD, I have my money on the band. Less likely is one of the solenoids but, if this was the problem, you would have trouble with other shifts.

HTH,

Chris

wildrage

I dropped the pan and changed the filter today and still have the same problem. The fluid looked fine and nothing was abnormal. When I orignally had the problem I had an error code. I forget exactly what it was, but something like "Transmission sensor out of range."...all the sites that I looked at pointed towards the nuetral safetey switch.

Could the problem I'm having have anything to do with the Neutral Saftey Switch?Orperhaps the linkage? I had to remove the linkage to pry off the rustedNeutral Safetey SWitch.I'm sure I aligned the Neutral Switch up properly when I installed the new one. Could either a faulty Neutral Saftey Switch or a problem with the linkage cause any issues with O/D? I didn't think it could, but wanted to verify it.

Also, any other things that I could check? I'm trying to explore all possibilities before brining it to a shop.

Thanks,


James

onesickstang01

hey i had the same problem, undo battery connection and then connect it, drive the car with O/D on and see if it still does it. if it does then it is most likely the band, if it doesnt do it at first the it could be the selenoid. but since your problem happens after a while anyway you might not be able to tell. id still say to try it though

nyuk98gt

wildrage:

OK, that extra info helps. There's a brake on/off (BOO) switch but that is easy to check out. If you moved the manual lever position switch (MLPS), then it is likely that it is not in exactly the correct position. The Haynes manual has a good write-up and you can find tons of threads on MLPS's at TCCoA.com (T-Bird and Cougar Club of America). There is an accumulator (piston) that serves the OD band and there might be some gunk in there. I am sorry to suggest that now that you had the pan off but I thumbed through the "Transmissions 101" last night and realized I should have mentioned the accumulator. Of course, if your transmission fluid is clean and the transmission clutches have never failed, then gunking up the OD servo accumulator is not very likely. That brings us back to the MLPS!

HTH,

Chris

wildrage

Would an incorrectly installed MLPS only cause problems with OD? I ONLY have the problem if OD is on and I thought a misaligned MLPS would cause neutral drops a little more randomly.

If it is the band (which unfortunately it looks like it is), I have a couple questions:

1. I'm assuming this requires a full rebuild, correct?
2. If it requires a rebuild, I'll probably shop for a low milliage direct swap. This may sound like a stupid question, but how dificult is it to swap a transmission? I've done basic things like alternators, water pumps, radiators, intake manifolds, etc. If it is way over my head, what price range should I expect to pay to get it swapped?
3. Until I make a decision on what to do, would it be stupid to drive the car at all? It drives fine with o/d off. I have another car but (of course) it's currently having issues as well. I wouldn't be stupid enough to drive it that far, but assuming the transmision needs to be rebuilt or replaced, I dont see what it would matter....and if it's the MLPS or electrical, then just turning the OD off shouldnt cause a problem.

Thanks for your help.

Jim

wildrage

Another Quick Question:

I read somewhere that the OD band also controls manual 2nd gear. Is this correct? I'm only asking because my manual 2nd works fine...

nyuk98gt

wildrage:

I will have to check the old ATSG to learn if the OD band is used for 2nd gear. I can't answer your MLPS question either. (I'm batting 1000).

** edit: Yes, OD is used for manual 2nd gear. So, if you have manual 2nd gear, the OD band is OK. My money is still on the MLPS or, maybe a faulty shift solenoid.
** end of edit.

For your other questions...

1. Just have to replace the OD band. I'll hunt around to see if somebody has posted a how-to. The ATSG does not say how to do "just the OD band" but it appears to be a matter of feeding the new band in and lining up the hole in the band with the servo (piston with a pin).
2. You should be able to swap out the transmission if you have a floor jack and some muscle. You may want to have a buddy help because the transmission is heavy and awkward to move around by yourself (especially under the car). I would figure 2 to 4 hours of shop time to swap out one for another but you are better off calling a (reputable) shop and asking for a ballpark price (time and materials).
3. You'll be fine driving around with OD off. Your gas mileage will suffer if you get much about 45 or 50 mph.

I'll go track down those answers.

Chris

wildrage

Thanks for your help. It's supposed to get up to a whopping 50 degrees here on Satuday (it's about 12 right now), so I'll get the car back up onto ramps and maybe check the MLPS again with a small mirror. If you think of anything else, please let me know.

Thanks.