Theoretically, is it possible for to change an automatic transmission car to a 5 speed manual? What would need to be changed, and about how much would it cost for the conversion?
You’ll need Homers input on this, but anyway: Theoretically, yes.
You’ll need to install a clutch as well, of course. Some cars are pretty well prepared for this (i.e., they come in a manual version as well, so the preparations for mounting a clutch have been made and you can buy the parts over the counter), some are not. It’s a major job under the best of circumstances.
S. Norman
Spiny Norman is right on both counts - it depends a lot on the car, and you should see if Homer can jump in here to contribute (if he gets his net access back).
My experience is that it is normally a Herculean effort, and one that you really should think twice about - and think about whether it might be easier and cheaper to just buy a different car.
Homer responded to this question for a 1990 Z24:
http://boards.straightdope.com/sdmb/showthread.php?threadid=32666
It sounds pretty involved to me! 
Arjuna34
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- It depends on a couple things.
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- One is that (as in the other thread) the car you are working with originally was available with both engine/transmission combinations, so all the ancillary parts are avilable. This can extend to interior pieces in annoying ways: if your automatic has a “digital” dashboard, but the manual transmission lever only fits into an “analog” console that fits into the “analog” dashboard, you can either cobble something together that will look trashy, or you can change your whole dashboard. Which then, if you’re using salvage parts, the salvaged dashboard likely won’t be the same color as the rest of the interior, and even if you buy a new dashboard it may not match the style of the other interior parts.
- Another is that you have a donor car with most of the pieces you need, because buying new pieces from the dealer is expensive. You need to crawl around over and under both cars before you spend any money at all, to try to get a real idea of how many pieces will actually be useable.
- The third, but by no means the least, is that you have a lot of free time and no pressing need for the car right away. As to how much it will cost, that depends on if you want something that looks and works perfect, or if you just need something that is drivable.
- I hear of people doing this with old cars fairly often, because with cars made 15-20-30 years ago, changing transmission types was usually a snap: they used as many identical parts as possible for both, and the interiors were designed to accomodate either. Nowadays it isn’t quite so. - MC
Before I can get more specific, I need to know what kind of car you have.
In my car (the Cavalier) it was a very detailed, yet straightforward, job, and isn’t difficult, if you know cars.
In any vehicle, you’ll likely need:
Shifter
Shift linkage
Brake Pedal
Clutch Pedal
Clutch linkage/master & slave cylinders (depending on transmission type)
Manual transmission console and trim
Speedo cable (possibly different length/connection between manual and auto)
Transmission itself w/bellhousing
Clutch, pressure plate, throw out bearing, shift fork, retainer pins, etc.
Park/Neutral safety switch
Ignition switch
Wiring harness
Possibly ECU
In a FWD, you’ll likely need:
Everything above
Halfshafts
Chassis support, passenger side
I don’t know the procedure for RWD, but I’d assume it’s pretty much the same.
A few things to look out for:
Make SURE that the crankshaft is drilled for a manual transmission. SOME engines have a manual crank and an automatic crank. The Chevy 2.8/3.1 does NOT, the crank is the same for both, that’s why my swap was so ever-lovin’ easy. Make SURE that the vehicle doesn’t have different spindles between the two different cars (only likely in a FWD), make sure that the engine compartment itself is the same (only in FWD) and that the engine mounts will line up. Before you start stripping the other car (and I’d get a junked car with the 5 speed, so you’ll know and have everything you need, even if it’s broken in the junked car, at least you know what you have), use fiberglass, or cardboard, or something, and trace the firewall so you’ll be able to drill and punch the auto car’s firewall correctly. Also, make sure that the bellhousing matches up to the engine. Sometimes, they’ll re-do the bolt pattern on the engine or bellhousing mid-year, transferring from a 4 bolt to a 5 bolt or a 5 bolt to a 6 bolt pattern for strength or durability or some other nonsense, so make sure they match up.
If this is a RWD vehicle, I can’t be much help, but I’m sure if you go to alt.autos.rod-and-custom or rec.autos.rod-and-custom or rec.autos.tech they will be able to.
On a more personal note, the ONLY reason that I did this to my car is because my car a) had all the options I wanted, b) wasn’t paid off yet and c) was only produced with a manual in 5%-10% of the run, in that trim level, making it VERY hard to find a manual like mine. I could also get the donor car VERY cheap.
It took me a week to strip out the old car and mine, and then a week to put mine back together. I haven’t put the donor back together or made it run yet, because I’m GODDAMNED LAZY.
If you have any more questions, I’d be more than happy to help.
I can’t receive Email right now, so don’t bother asking that way.
–Tim
If it helps, the car in question is a 1987 Nissan Maxima. It’s a third-hand car with less than 100k on it. IIRC, it’s a RWD car.
Uhhh… well… I don’t know.
I am only familiar with working on domestic cars, sorry.
Was it MADE as a manual? Most luxury cars aren’t, unless they’re a ‘sport-luxury’ mutation.
Who makes the engine? Nissan, or is it a domestic collaboration?
Maybe there’s a alt.autos.makers.nissan that you can ask around in.
Sorry I can’t be of more help.
–Tim
I’ve never seen a manual Maxima. And that’s in Europe.
A 1987 Nissan is hardly a classic either, so I’d say buy yourself a new car.