[Transmission] Screw it, I'll do it myself.

[ootdega]

AOD is going out, and it's going out fast. Problem is I am poor, and living isn't getting any cheaper. I've already tried the easy stuff, and that helped for a while.

I have two other AODs, and I've taken one of them apart. The other one is two bolts away from removal. I have a master rebuild kit and a shift kit. The disassembled one was in pretty good shape, but a few parts were left in the elements and they're ruined. Sun gear with drum and clutches. Might just buy a new one preassembled if I can.

I won't be able to install it myself, but I can at least rebuild it. I have multiple manuals, but I thought it would be prudent to ask you fellas for input.

The donors are from a 1989 and 1990 Grand Marquis. The one being replaced is a 1989 Crown Vic unmarked interceptor. It has everything but the exhaust and cooling. I don't think the police package changes anything about the transmission, but you folks know for sure. I'm pretty sure the engine has had work done, though. It's not an HO, but it has noticeably more power than the Mercury had. I'm sure this is exacerbating the problem.

What should I look out for and what would make this easier? I'll have to do it in my living room, for the record. When I say poor, I mean REALLY poor.

[sly]

police package changed the shift pattern. Police went PRNOD2 instead of PRNOD1 and had a longer tailshaft housing by about an inch. That's pretty much it.

As for making things easiest... rebuild into the 89 case. It has the proper shift lever angles since 90 changed to the cable shift lever setup from the rod setup IIRC. You may be forced to rebuild into your currently in use housing if the tailshaft housing is different since the output shaft will be longer as well. You can use the other cases if yours has the short tailshaft housing or you have the longer driveshaft to swap in as well.

[gadget73]

what he said about the shift pattern. The valve body is slightly different. Somewhere I've seen a pic of what specific valve is different but I don't remember where.

The cases are the same, its just the shift lever thats different. It needs to come out as part of the rebuild anyway, there are seals for the shift lever and the TV lever that goes through it which should be replaced. You can swap the lever to the 89 part but honestly there isn't any point in taking apart 2. 1989 was the last revision for the case and internal bits so they ought to be identical, assuming both cases have an E9 part number on them. If one is earlier than E9, its not original and I'd probably vote for not using that as your core if you have the option of a later unit.

These should all be the same tailshaft length but a tape measure will confirm. Difference is about 1 inch. Only Lincolns got the long output so far as I know.

Maybe consider swapping to the "A" or A+ servo for the overdrive. It applies more clamping force. At a mininum, make sure its a B servo, not a C servo. Stock should be B but some early ones used a C. I had an official Ford reman in my first Mark VII and it was an early case with the C part, where it should have been a B.

There is something about a set of seal lip protector tools you'll need for assembling all this. Looks like a bunch of plastic plumbing fittings.

when you take it apart, its going to make a mess even if you drain it so have pans to try and contain the inevitable bloodletting. Haul the case to the carwash and blast it as clean as you can get it, or if you have a dishwasher you don't care about and never want to use for dishes again, stick it in there and give it hell. Maybe find one on the side of the road that works and just cobble it up to the garden hose. Only needs to work once. Dishwashers actually make pretty good parts cleaners.

[matth825]

I think the valve that is different is the 1-2 shift valve. Selecting the “2” position locks out first gear forcing a second gear start.


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[gadget73]

that would make sense, I just know somewhere I've seen a pic of the two valves so you can ID what you have in case of a mystery valve body.

[ootdega]

The cases are the same, its just the shift lever thats different. It needs to come out as part of the rebuild anyway, there are seals for the shift lever and the TV lever that goes through it which should be replaced. You can swap the lever to the 89 part but honestly there isn't any point in taking apart 2. 1989 was the last revision for the case and internal bits so they ought to be identical, assuming both cases have an E9 part number on them. If one is earlier than E9, its not original and I'd probably vote for not using that as your core if you have the option of a later unit.

I will have to take apart both. The one I took apart was the 90. The 89 is still in the Mercury. I need to leave the one in the Vic alone so I can still drive it. I don't have anywhere to put the car anyway. The Mercury is already taking up half my mom's backyard.

The 90 needs parts from the 89 to replace the ones that were left in the snow (against my will). I kept the rest in a Tupperware bin and WD-40'd the shit out of them, so they should be fine. Finding all the sprag rollers will be a pain, but whatever.

The shift lever won't come out either. That stupid pin is stuck. There's a trick I haven't tried, but I might as well just use the other case anyway.

Maybe consider swapping to the "A" or A+ servo for the overdrive. It applies more clamping force. At a mininum, make sure its a B servo, not a C servo. Stock should be B but some early ones used a C. I had an official Ford reman in my first Mark VII and it was an early case with the C part, where it should have been a B.

That part is more expensive than I was expecting, so it'll have to wait, but I need to fix this damn computer to get it out of way first regardless. It's been sitting here in a hundred pieces taking up space for several months, and the backup PC is set up on a chair in front of the couch. Depression is a hell of a drug. I hate my life, if you couldn't tell.

As for making things easiest... rebuild into the 89 case. It has the proper shift lever angles since 90 changed to the cable shift lever setup from the rod setup IIRC. You may be forced to rebuild into your currently in use housing if the tailshaft housing is different since the output shaft will be longer as well. You can use the other cases if yours has the short tailshaft housing or you have the longer driveshaft to swap in as well.

The tailshaft won't be an issue. I've already been through that rabbit hole when researching the Mercury project.

Haul the case to the carwash and blast it as clean as you can get it, or if you have a dishwasher you don't care about and never want to use for dishes again, stick it in there and give it hell.

Funny enough, I do have a spare dishwasher. It's a countertop model, but it should be fine for most of the parts.

police package changed the shift pattern. Police went PRNOD2 instead of PRNOD1

I just know somewhere I've seen a pic of the two valves so you can ID what you have in case of a mystery valve body.

Couldn't I just...look at the dash and see if it ends in a 1 or a 2? Did they bother to change that?

In theory, shouldn't I just be able to swap in the valve body from the Vic? That part is easy to remove.

[sly]

Yes, if the trans has not been modified from original, checking the dash will sort out the valve body shift pattern issue.

[gadget73]

right, only question is if someone used a non-police trans in a cop car, or put a police trans in a civi car. Or if someone changed the cluster for some reason. We're talking about a 30+ year old car, lots of things may have been changed by now.


The police cars were 140 speedos and had "2" as the lowest number though. I don't honestly know about the regular P72 fleet models, they were probably not 140 speedo but I don't know about the transmission shift pattern.

[ootdega]

It's probably a detective cruiser. It has all the goodies except the ones that would be visible. Aside from the push bar; it definitely had one of those from the factory, or at least provisions for one. VIN number history is blank, other than that it was apparently built in Canada. Kinda spooky.

It definitely wasn't a civvie retrofitted with police parts. It has the reinforced frame and a siren switch. No evidence of standard front suspension.

The cluster is an 85, not 140. Shows PRND1. But I mean, I don't get the impression that using a standard valve body would make a significant difference either way.

[gadget73]

no, you just need to know which you have if you plan to put a shift kit in or something. There is also an early and late transmission and the valve bodies go with the case. The later transmission case has a hole in it where it looks like something should be, the early ones had an accumulator in that spot. The late ones re-located that part to the valve body.

https://www.cartechbooks.com/blogs/techtips/ford-aod-and-4r70w-transmission-history-and-evolution

about halfway down you'll find a pic of the trans with the valve body out and 3 round things visible. The smallest one is just an open hole on the late version.