JDM 2000 BH5 4EAT to MT swap - questions, I’m so lost

[Twitch_6]

Hello all. First off, this is my first post on LegacyGT, so if I’m doing this wrong please forgive me.

 

As the title says, I have a JDM 2000 Legacy GTB E-Tune (BH5) with the 4-speed automatic that has the “semi auto” shift buttons on the wheel. I’ve had the car for roughly 18 months, and I love it. It’s my first “nice” car (aka not a beater), and my first turbo car. I bought the car with about 85k km, it has just over 104k km, and for the most part looks like new.

 

Over the last several weeks, I’ve noticed an increasing “clunk” when shifting into reverse. It doesn’t do it all the time, sometimes it clunks when I shift into reverse after being parked, sometimes it clunks when I shift into reverse while driving. More recently, within roughly the last week, I’ve noticed the clunk randomly happening when the transmission downshifts from 4th to 3rd. Again, this doesn’t happen all the time, it tends to happen when I’m braking down hill, and the transmission downshifts to 3rd around 70ish km/h. I can also replicate the clunk by putting the transmission in “manual mode”, and downshifting from 4th to 3rd, or 3rd to 2nd. Again, it doesn’t clunk every single time, but it does it randomly.

 

So here’s my questions and dilemma….

 

First, is this a known issue with these transmissions, and is it a relatively simple fix? The car had a transmission flush about 2 years ago, roughly 20-25k kms ago.

 

Second, and this is my bigger issue…as of right now, I would like to keep the car long term, and slowly work on building it. As such, I have a really hard time justifying spending money to fix the 4EAT transmission when my goal is to swap it for a manual. I know my two options are either a 5MT with upgraded gearing, or a 6MT from an STi.

 

But that’s about as much as I’ve been able to figure out before being overwhelmed with jargon and things I’m not familiar with. I do most of my own maintenance, I’ve pulled a 2.5 motor and done head gaskets on an old Impreza I had, but I’ve never done any kind of swap before.

 

1. Will a USDM manual, either 5 or 6 speed, work in my JDM car? Or do I have to source a manual transmission from Japan?

 

2. What model years are options in terms of donor cars? Both for either a 5MT, or a 6MT.

 

3. Ideally, I would be interested in buying a rebuilt transmission. I live in BC Canada, are there any companies that sell rebuild Subaru MTs? Or more specifically, would rebuild a 5MT with heavier duty gears (I’ve read the stock

5MTs are a bit like glass). I’ve read that there are some shops in the US that do this…is it reasonable to buy a rebuilt transmission in the US and ship it to Canada?

 

4. What other parts am I looking at requiring? A clutch and associated parts of course, but do I need a new rear end as well? New drive shaft? New rear axels?

 

5. And lastly, money. Roughly what am I looking at paying for all the required parts, if I do the work myself? Roughly what would it cost to pay a shop to do this job? Are there any reputable shops in western Canada that would do this job?

 

Sorry for such an open ended question that I’m sure has been asked and answered several times. Like I said, I’m a bit overwhelmed with everything at this point, but I’m really stressing about what to do with my car. It’s not my daily driver (I have a company work van), but it is my only personal vehicle, and I can’t really afford to buy something new (or if I do, it’ll be another beater).

 

Thanks in advance for any help. Additionally, if there’s any threads or guides on this forum that would help me or point me in the right direction, I would greatly appreciate any links. Cheers

[doublechaz]

I don't know about the swap, but your current symptoms sound like a dead trans or engine mount, or less likely a ujoint or the carrier bearing.

 

Ideally you would have an assistant shift it back and forth from forward to reverse while you have the hood up standing beside the car, not in front, watching and listening for the origin of the noise. Also, on the ground beside the car, not in front, if a lower angle is needed.

 

I rate the 5MT as fine when it is asked to do what it was designed to do. If you are going to run double the torque through it that the designers expected, then yeah, it will blow up. If you are going to run 250 ft lb then go with the STI trans that was designed for that. If you are going higher then you'll either have to go built or accept the failures. Passenger car tires fail when you put 70 psi in them. Guns blow up when you make your own ammo with double the powder. Your ankles will break if you jump 19 feet.

[Twitch_6]

I don't know about the swap, but your current symptoms sound like a dead trans or engine mount, or less likely a ujoint or the carrier bearing.

 

Ideally you would have an assistant shift it back and forth from forward to reverse while you have the hood up standing beside the car, not in front, watching and listening for the origin of the noise. Also, on the ground beside the car, not in front, if a lower angle is needed.

 

After talking to a couple people, I’m starting to think you might be right that it’s a transmission or engine mount, or maybe the rear diff bushings. I did a bunch of testing earlier this evening, driving the car back and forth trying to repeat the clunk. It tends to happen most often when I drive forward, stop, and put it in reverse. The more gentle I stop, the more gentle the clunk is, but it’s there almost every time. And from the driver’s seat, it sounds and feels like the clunk comes from the rear of the car.

 

That’s a good idea to have someone help me diagnose…I wouldn’t have thought of that lol. I’ll follow your safe advice.

 

Is the carrier bearing that you mentioned the one in the middle of the drive shaft?

[doublechaz]

Yes, the carrier is in the middle of the drive shaft. Good idea on the diff bushings as well.

 

Finding noises is not easy.

 

Another thing you can try if you can't find someone to help is to do the test next to a building or a retaining wall that the sound can bounce off. It helps to be able to position with a wall on one side and then the other. It's pretty hard to find one for each side where traffic and background noise work well for this.