Gone through 3 "genuine good used SVX" (3.54) trans that were trash for one reason or another, I went to the junkyard and bought a '98 Impreza 2.2 4EAT, which has a 4.11 rear end, so I also bought the driveshaft, differential, and axles and the TCU, hoping to swap the whole lot into my '94 SVX.

Both boxes are phase one with what seems to be similar wiring, but my mechanic  thinks the SVX TCU will "not work" on the Impreza box, and using the Impreza TCU may make the car refuse to run at all.

I, of course, am perfectly ignorant about all this, and not sure I understand his argument.  I do know that my car must have a phase 1 gearbox in it to smog in CA, which rules out the desirable 5- or 6MT swap, and phase 2 (99 and on) won't smog either.

Help, I'm in over my head., thought all phase 1 boxes pretty much interchangeable, given the rear end ratio is matched..

I can't really help with details about all that (sorry) but i do have a tranny out of a 94' SVX that had a rebuild 10k ago. Would be willing to sell and ship it if you wanted.

How much?

We don't know anything about your mechanic but if they're not well versed in Subaru's, particularly 90's Subaru's and SVX's, then they're going to know a fraction of a percent of what is possible with an SVX and many other Subaru specific conversions, interchanges, and swaps. 

SVX tcu will run the trans but won't like in a gearing sense.  Just have to make sure the wiring is proper because the harness plugs may be different but basically everything else is the same.

 

It will see a different RPM to Speed rate and maybe throw a code.

 

But ultimately will work.  

It will work just fine. Your mechanic doesn't know Subarus. Find a qualified Subaru mechanic.

 

GD

We don't know anything about your mechanic but if they're not well versed in Subaru's, particularly 90's Subaru's and SVX's, then they're going to know a fraction of a percent of what is possible with an SVX and many other Subaru specific conversions, interchanges, and swaps. 

I've come to know that Subaru information on the net is plentyful.  Every question I've ever asked has been covered in three possibilities. (1) Yes, it will work.  Everybody knows this. (2) It'll never work and if you try you'll damage the car.  Everybody knows this,  (3) Sometimes it may work, when the moon is in the 7th house and your mechanic is fluent in Japanese. Everybody knows this.

(sigh)

The transmission that is in the car is a proper (3.54) 4EAT, but one of the ring gear teeth fell out with the last oil change.   The trans itself seems OK, and since it seems that I may not be able use the junkyard box I bought.  I've had another thought.  Since I have 3-4 dead tranmissions with good R&P sets, why not just change out the busted set for another used set?  Back in the day when R&P sets were face milled, this would be a big no-no, but now a-days they are hobbed.  I know that Subaru will attach a variety of ring gears to a pinion of a certain tooth count, I wonder if hobbed sets don't care as much about being perfectly matched.  I also wonder if the R&P sets can be moved without eventually failing..

 

Any working machinists out there?

Edited September 3, 20178 yr by briankk

The ring and pinion SET can be swapped from one transmission to another, as long as you know how to set the pinion depth and backlash properly. 

 

A ring gear from one ratio will not match to the pinion of another. No way. 

Understood.  Let me put it another way.  A given R&P set is used for a while, or a long time, then moved to another g-box, and properly set up.  The question in my mind is will the re-setup in a different g-box cause a new wear pattern to be superimposed over the old wear pattern, and if so, will it accelerate the deterioration of the tooth hardening, and eventual failure that would not have happened if the R&P set had been left alone in the old g-box?

yes you can swap sets.

 

Just get the backlash setup correct

I, of course, am perfectly ignorant about all this, and not sure I understand his argument. I do know that my car must have a phase 1 gearbox in it to smog in CA, which rules out the desirable 5- or 6MT swap, and phase 2 (99 and on) won't smog either.

This may seem like a stupid question but I'm ignorant to the laws of that state...

How would they ever know you swapped the transmission? This is a car that barely exists. How many mechanics in that state, or even the whole country will be versed well enough in Subarus to know its been swapped, and if it works properly why would they even care to report it? I know they have tough emissions laws there, but seriously, a transmission is a plucking transmission.

This may seem like a stupid question but I'm ignorant to the laws of that state...

How would they ever know you swapped the transmission? This is a car that barely exists. How many mechanics in that state, or even the whole country will be versed well enough in Subarus to know its been swapped, and if it works properly why would they even care to report it? I know they have tough emissions laws there, but seriously, a transmission is a plucking transmission.

 

it's got to match the VIN.  Primarily rules out a swap to manual.  

 

They just will want to know it's an Automatic and must have no codes thrown.

 

So the phase II trans won't work electronically.

This may seem like a stupid question but I'm ignorant to the laws of that state...

How would they ever know you swapped the transmission? This is a car that barely exists. How many mechanics in that state, or even the whole country will be versed well enough in Subarus to know its been swapped, and if it works properly why would they even care to report it? I know they have tough emissions laws there, but seriously, a transmission is a plucking transmission.

In much of CA, most gasoline powered cars are required to undergo a state smog examination,every two years, without which you can't register, or re-register the car.

The smog guy has a list of cars and their requirements, this list is of all the cars allowed in the state, and their OEM equipment.  You present with a car not on the list.. Good-by.  Caught driving a car not on the list, you get arrested and the car is confiscated and destroyed, similar to the fate of car that has been "tampered with", i.e. has equipment installed thats not on the list, or had equipment that is on the list, removed.  Now the important thing to know about this smog stuff, in California, at least, is that the State doesn't care why or how the car has been "tampered with", it just fails, which is the problem with the SVX.  There never was an SVX made with a manual transmission, and the state knows it. Smog check fails right there, theirs nothing you can do about it but to move to a free state.

Now, it happens by chance I live in a bit of CA that does not require bi-annual smog checks, only smog on transfer.  In other words, it smogs when you buy it, but never again.  There some quite unusual vehicles lurking out here in the woods and that has me thinking....`  My SVX runs like a watch, the engine is perfect, throws no codes, I replaced several of the engine sensors and all the vacuum hoses (blue silicone), but the trans has a broken-off ring gear tooth (came out with the oil change), but the TCU doesn't know that, theres no code thrown  I wonder if I were to show up at the smog place, the car might not actually pass, the smog guy does not drive the car, he checks equipment off his list, sticks a probe up the exhaust and checks for codes..  

Then, having it smogged and registered, I could stick in a 5-MT and go my way..

Just thinkin'...

There are states with inspection/emissions that only happens on transfers and it happens exactly like you're thinking.  Transfer, inspect, emissions testing - and then do whatever you want for the life of the vehicle, it doesn't matter.  Very common.

If a tooth is broken off of the ring gear it would make one hell of a chunking noise and lock up when driving. You confirmed the tooth is missing off the gear by looking up through the drain hole?

You bet it makes a hell of a noise.  I suspected the problem upon first drive with "new" transmission installed.  Back to shop, pulled drain plug, out came tooth and various other small metallic bits.  Re-filled diff housing with clean bulk 10/40 motor oil and drive it home, a bit over two miles, it sits in my yard as we speak..  The drive between my place and the shop is reasonable flat, couple of small hill, nothing worrisome, discovered that under load, or backing off throttle, noise gets pretty severe, but at 50-60 mph, feather the throttle and coast, hardly any noise at all.  For what it's worth..

drive it until that broken tooth wears into adjacent surfaces and see if it quiets down?!

LOL