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Yes the newly rebuilt C4 is working just fine (pat on back), but I really don't like it reving around 2600 going down the highway. I think this summer will be a good time to consider putting in an AOD but first a couple questions. 1) What is the typical rpm for say 70mph? 2)What is the best year range of an AOD to look for? 3) What year shifter assembly is required and will it work with our console ? 4) I assume an AOD is longer and I would need to find either a shorter drive shaft or have ours cut? What are the negatives of doing this?

Kinda wish I had just done this back when I yanked the C4 a few weeks ago, but "oh well". If I green light myself on this project I'll first rebuild the AOD during latter winter/early spring, then when I'm absolutely bored :jawdrop:.....
 

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1) I'd say about 1900rpm with stock 2:80 gears.
2)88? and up have oiling upgrades, but any really.
3)It's not too complicated to get the vintage shifter to work
4)Not nessecarily. An LTD yoke is usually short enough to fit on the un-modified stock driveshaft, but these things will vary after 40 years.
HTH
--Kyle
 

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2600 rpm is not bad on the highway if you are going 60 - 70 mph. I would be happy cruising at 2600 rpm. Are you planning on running 90 mph + consistently? What rear gears are in your car? Maybe a gear swap would solve your problem. If you decide to do the swap you will need a new crossmember and some electronics. Good luck.
 

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You can review Hoosierbuddy's Mustang webpages for the ultimate in an AOD install.

John Harvey
 

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I used a '85 Lincoln Town Car AOD. I did not want to get into the electronics. It has since been rebuilt with upgrades and it is real sweet. 1400 rpm at 55, 1900 rpm at 70. The shifter I made myself by combining the two. Used the C4 part for hook up to the shifter and the AOD to connect to the trans. Cut and welded the two together and it works good. Stock shifter was able to come real close to being perfect on the shift pattern. A bit of fine tuning on the shift stops on the shifter helps. Mine has as manually selectable gears P, R, N, OD, D & L. Made the cross member as we installed the trans. Simple task. Still have to re build the e-brake cable system. I had the drive shaft shortened & balanced prior to knowing that I could just change the yoke. I am real pleased with the outcome. Be sure to put a shift kit in the AOD. Not sure of the flywheel/balancer changes as I used the engine from the same car so it was a package deal. Cooler lines are a bit different but easy to make work.
 

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Discussion Starter #6
TJH,
I'm running 3.0 gears in back. Don't know if going 2.8 would make that much difference, then again, what do I really know anyhoo? Well I'll (I mean the daughter :lol:) be putting in a few hundred miles before I make such a swap. Yes, I should study the suggested website on this particular subject.
 

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The old 3 speed transmissions are severly outdated by modern standards. Many are swithing to 4 speed overdrives to allow for lower RPM's at highway speeds (better fuel economy). It's no different that the 4 speed guys switching to 5 speeds. Try this link for kit info
windsor-fox.com/main.htm
BTW, 1988 and later are ideal, you won't need electronics unless it's an AODE.
 

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You will like the AOD on the highway. I currently have 2.79 gears and pull about 1600 on the highway. I would guess you would be pulling about 1700 or so. When I had the 4.11's in there it ran about 2300 or so, but it was still very nice.
 

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If you get one from a truck or Town Car it will have a longer tailshaft and you WILL have to shorten the driveshaft. These "long" transmissions have been known to crop up in TBirds and Cougars though it's rare.
The 89 and up AOD's have a couple of upgrades here and there. Notably improved "rear" lubrication. They had some failures in early police cars during "extended high speed operation". This doesn't actually affect the rest of us so I wouldn't worry about it. The most sought after used transmission is found behind TBird "SuperCoupes". Big OD servo and bands. A very closer second would be a truck transmission. I find it intersting that the budget version of B+M's shift kit isn't very useful on a truck AOD as most of the "mods" were already done by the factory.
Generally the newer the better.
You can rebuild an AOD if you've been into C4 successfully. Be aware that you HAVE to have the $90 seal installation kit to assemble one though. No way around it. Unless you can borrow one somewhere like I did.
The only negatives I can think of is that the AOD is bigger and heavier. You will actually lose a tad bit of MPG an HP due to this. It's more than made up for by what you gain with having OD though. And IMHO, all else being equal, a C4 will outlast an AOD every time. The last down side is that once you go AOD, you're ruined. My AOD went out in my truck and I happened to have a spare C4 at the time so I put it in. Drove me nuts, I kept wanting it to shift into that 4th gear. I shortly found another AOD to go back in there.
The only negative to having the driveshaft cut is the price. It will have to be balanced afterwards. The shop that does this around here says that maybe one in a hundred used driveshafts that DOESN'T need balancing. Never minding the ones being cut or modified. Most serious racers seem to get their driveshafts balanced as a matter of course.
 

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I looked into making this swap but decided instead to go with this, http://www.gearvendors.com/index.html

Pricey? Well, yes it is, but I would need new headers, exhaust work, and an AOD that would be built to take the HP and torque my stroker has. After adding up the costs and aggravation I decided to install the GV unit. I have yet to start on this, I will be soon as I am far enough along with the EFI install to get under the car to do some plumbing.
 

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Pricey? Well, yes it is
Is one of those "if you have to ask..."

Doooooh, never mind, I found it :eek: :eek:
 

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I am currently doing this. I drove around town one day, (Bad part of town)found several parked crown vic's, ford Ltd's and some Mercury Marquis. I went up and knocked on about ten doors. Five or six of them were willing to sell for 250.00 or less. I found one for 100.00 from an 82 Mercury. I found an article on Mustang monthlys web site. found some articles on here and Johnpro walked me through everything. Went on Ebay and found a torque converter with a 2500 stall speed that was built by Midwest converters that had less than 600 miles on it and paid 107.00 ordered the master rebuild kit today from EBay for 95.00 I should have this complete in two weeks and give me an email if you need anything.
 

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you can use your stock converter, but I wanted something with a 2400 to 2800 stall speed. I think johnpro's was stock for a while.
 

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2600 rpm is perfectly normal at 65-70 mph with a 3.00:1 rear end. That is right in the sweet spot of SBF torque curves. I'd recommend against the AOD in Red, since it would allow the car to go to a higher speed than a non-AOD. Do you really want your daughter to be driving that fast? Think about it...
 

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I think johnpro's was stock for a while.
While I had a stock converter, I never used it. I'm using the B&M Holeshot 2400, and installed it the day I installed the AOD.

No mods to the drive shaft if you have the short tail shaft, and use the AOD yoke. You can use a C4 yoke, and have just the yoke cut, as well.

Now, maybe freeway traffic just drives faster in Sacramento than the rest of California, but the only way I see someone turning 2600 RPM's on the freeway with a 1:1 drive ratio and 3.00 gears is in rush hour *LOL*. If it were possible for me to run at 2600 RPM's on the freeway, I would never have bothered with an OD transmission.

My '66 with the AOD and 3.50 rear turns about 3000 RPMs at 75mph. Both my kid's cars with 2.80 gears turn about the same with their C4's.

2600 on the freeway would never bother me!
 
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