View Full Version : AOD, OD problems

06-08-2004, 11:19 PM
90 SC AOD, car shifts fine around town, 1 through 3rd, when I get on the highway OD works fine for about 8-10 minutes at 70mph then all of a sudden slip, bang ba bang bang, quickly throw it in neutral and pull over, once I come to a stop I can bring her back up to 40 or so....then push it up over 45 to let her drop into OD and then its fine but the banging and slipping comes back sooner probably within 2-5 minutes.... This only happened 3 times in an effort to determine if this was a tranny problem or if it was a half shaft or bearing grinding up. I drove it home in 3rd to be safe. Turns out definatley not a half shaft problem. I jacked up the car put it in neutral and tried to sping bother rear tires, there is a squeaking that comes with the spinning of the drive shaft but the noise is coming from the tranny. Rear tires do not spin freely. Ideas? How messed up do you think my tranny is? Car has 56k on it, bought it from original owner with 13k. While in my posession I have only spun the tires by accident in the rain, I have completely babied the car. The only time I have wacked the throttle is in frustration of Rt 128 and Rt 93 traffic in Boston at higher speeds, shifting down from OD to 3rd at about 50\60 mph (not manually via moving the shifter but just by opening her up to WOT). I had the tranny fluid\filter changed at the Ford Dealership locally at 35k miles. Everything was fine until now. The only item I replaced related to the tranny was the plastic grommet on the TV cable. (Broke while removing in order to remove the throttle body to re-torque the lose valve cover bolts), I replaced it with the nice brass one w\clip from Ford. I never adjusted the TV cable, I just put it back the way it was. I was told there is another grommet on the tranny side under the car, could that have popped causing me to fry the tranny? Or mess up the TV cable settings?

Not sure what else I can tell you so that you guys might be able to offer me some advice.

Being a tranny novice, what does the valve body control in the tranny? How would I check it? By reading other posts I thought I might start there.

Thanks in advance.....
Derry, NH

stocker 89
06-09-2004, 01:20 AM
Is my guess. When a AOD gets old its clutch packs are used up and worn out in your case it could be a worn out OD band. You could need a rebuild. Is it possible sombody switched transmission before you bought the car? What happens is with cool thicker tranny fluid the bands and packs are able to grip better but as soon as the fluid gets thin and hot that is when the problems start to present themselves. I had a trans where it was all good for the first 20 ta 30 minutes as soon as the trans got hot and went into heatsoak it would start to slip in first and OD .I thought it was a outawack transbreak at first turns out it was just old and wornout. This trans also had over 100,000 miles. A transmission fluid cooler will keep temps down and add years of life to your transmission. Makes me wonder why ford didn't put a cooler on stock.......

06-09-2004, 02:50 AM
It sounds to me that the OD band is burned out. I would bet that after a few minutes in OD at 70 mph for example the band heats up from the small slipping that is going on, then expands from ther heat and quits holding. The next time you have trouble just move the shifter to D while on the highway. The rpms will shoot up some, but that is becasue you are in 3rd gear now. If the trans acts fine in D, and only has problems while over 45 MPH in OD then you have found the problem. Unfortunately, you have to disassemble the trans to replace the OD band. This means a complete rebuild to regain the OD gear. Most likely you are ready for a complete rebuild as all the clutches are getting thin by now. How many miles does the car have on it now?


06-09-2004, 02:55 AM
try some LUCAS TRANSMISSION FIX, see if it helps, get 2 bottles just to be sure. that stuff is thick like syrup, mmm mmm good

06-09-2004, 07:37 AM
try some LUCAS TRANSMISSION FIX, see if it helps, get 2 bottles just to be sure. that stuff is thick like syrup, mmm mmm good :eek: :eek: THAT,S THE GOOD STUFF!!!!!!! :D :D

06-09-2004, 08:19 AM
you will need a rebuild because the OD band isn't the only thing that gets cooked. the longer you drive on the thruway in D the more parts you will get to replace. the transmission additives will buy you a little time but they do not replace ground up metal pieces and burnt OD bands. have it rebuilt with a kevlar OD band and a shift kit. a shift kit and tranny cooler will help it run cooler and last longer. or , if you're rich get an Art Carr or Lentech. I'm sure someone would chime in about those miracle transmissions.

06-09-2004, 07:55 PM
thanks for all the replies, I figured it was the OD band as it only happens when I am in OD. I put 80 miles on the car after the first time it did it. My buddy in college had a 90 SC and cooked his OD band and it cost him $900 back in 1992. I fully expect this to be a big $$$ job, the question is if it cost him $900 back in 1992 I am sure that could easily be $1300-$1500 now. So if that's the number then the Art Carr for $1450 almost seems like the simplest thing.

So next question? Are there any New England (MA, RI, NH) SC guys out there that know a good tranny shop? I may have to get hooked up with the local Mustang Club, they might have a shop that sponsors them and would certainly know the ins\outs of the AOD.

Thanks for the help, why couldn't this thing have blown up last November and not this Spring!! Dam! Been waiting all winter to drive my SC :-) For now it sits in the garage while I keep my 92 Wrangler putting along....

06-10-2004, 02:30 PM
It costed me $900 to have my tranny rebuilt this past december. They installed a kevlar OD band and a trans-go shift kit which I already had. I'm very pleased with the shift kit. They didn't seal the dipstick tube too well though so now it has the drip. too bad i moved 1800 miles away because they guarantee their work for 6 months.

06-10-2004, 03:36 PM
The leaky dipstick is a result of idiots working on the trans. They pay some dude to do the R & R and that's all he is capable of doing. This results in bent dipstick tubes and tubes that leak. These places don't take the time to remove the dipstick before dropping the tranny and upon install slop some RTV on it instead of replacing the o-ring seal.

Don't get me started on Transmission shops. :mad:

If it were me I would drive on the trans in D until I could find a reputable shop. You aren't going to do anymore damage to the OD band and everything get's replaced if they do a good rebuild anyway.


06-10-2004, 04:05 PM
It costed me $900 to have my tranny rebuilt this past december.... they guarantee their work for 6 months. The shop I talked to was looking in the $1300 range for the job and gave a 2yr/24,000 mile guarantee. 6 months, to me, sounds shoddy.

Here's why: If the OEM tranny is warranted by Ford for 7yrs/70,000 miles, why doesn't a rebuild have something close? If the job is done right, it should be as solid as new. I can understand that a shop is worried about abuse, but if Ford wasn't, and they do the job right why shouldn't it be at least a 5/50? If it isn't as good as new, why not just go buy a new one for the same price? :confused:

Unfortunately, I think finding a good shop costs a lot of time and $ to research and read the print. When you're looking, go look at the shop floor to see just how organized and clean they are.. ask where they get and what brand of rebuild kits they use, how long it takes for each step. Finally, ask for referrals that you pick that are at least 1 year old, and call the BBB. That's about all you can do, short of interviewing everyone who walks through the door.

06-12-2004, 10:11 AM
for 1300 you may as well get a new lentech tranny and install it yourself.

06-12-2004, 10:27 AM
go on e-bay and search aod, you should be able to pick up a rebiuld for 499.00 with warranty and clutch packs made for 400HP

06-12-2004, 11:54 AM
...or rebuild it yourself. Its not that hard to do.


Randy N Connie
06-13-2004, 11:46 AM
92bird Do you have a e-mail address's where all the parts can be purchased
to rebuild a 1990 and 1993 SC AOD transmissions.That would be a upgrade.
And any specal tools needed.

Thanks RANDY

06-13-2004, 12:16 PM
Randy, the only special tools you need are the lip seal installers. These are a must. A clutch spring compressor is helpful, but a couple of "c" clamps will suffice as well. Bushing installers/replacers are needed, but if you are just doing a one time rebuild for yourself, you can take the parts down to a trans shop an they will install them for you (They might charge you $5 or something, but cheaper than buying the install tool)

If you haven't already, check out this article I wrote about rebuilding the AOD: Inside your AOD (http://b10.ezboard.com/fthunderbirdundergroundfrm1.showMessage?topicID=65 12.topic)

The trans I built in that article is for sale, too. It has many upgraded parts. Email me for more info. I'm selling the trans without a valve body, so you'd have to get a lentech VB or similar. I built it for a friend who was supposed to paint my car, but he flaked on me so I'm stuck with it now. If it doesn't sell I may drop it in my '92 SC (330.5 rwhp and 402.8 tq) in lieu of the M5R2.. It is a very thorough rebuild and all the clearances have been logged and are in spec. I'll sell for a fair price, or trade for some cool SC stuff.

Also, you can buy performance rebuild kits on Ebay. I've dealt with a few of those guys and have been satisified with both their product and service.

Jeramie [email protected]

Randy N Connie
06-13-2004, 12:27 PM
Jeramie I read your post on the TBU,NICE.I have two AOD's I want
to rebuild.A 1990 & A 1993.I want to do two because I don't look
for either one to last over about 200 miles.Two AOD'S should get
me to the track and back for two to three month.I get about 6
passes at the track and the AOD is junk.

If I would buy yours and rebuild two more.I might be able to drive my SC all summer.I have another AOD to if I would have 4 rebuilt I might even get to run into the fall.

Thanks Randy