Looking to change over to an Automatic

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5050GRIP
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Joined: Thu Dec 27, 2012 1:06 am

Looking to change over to an Automatic

Post by 5050GRIP »

I have a 2003 5SP non turbo, and have to commute to the city, it has been a pain in the arse over the last 2 years of commute. The current gear box is on its way out, only a little life left in it. I was going to just swap out the gear box to another 5 speed but I thought that I would give a slush box a try since they are more than 5 times more plentiful than what I currently have.
So far what I know, I will need a new ECU, shifter knob, maybe tranny cooler and THATS IT!
What else will I need to swap over to a ready to drive auto box?
Acro2pilot
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Re: Looking to change over to an Automatic

Post by Acro2pilot »

TCU, wiring harness, entire shifter assembly w cable, front axles, not sure but possibly the rear driveshaft, trans mount, pedal box, and I am sure I missed a few bits. Be sure to verify front and rear ratios match exactly. Another swap to consider would be to stay manual and swap to an STi 6 speed from a JDM importer. I don't know where you live but they are all over the place, VA JDM here in D.C. is good. The swap is pretty well documented and that trans can take a ton of abuse. If your thinking about staying with stock size tires this would work well and be plenty strong enough for a later STi engine or H6 swap. If you thinking about a lift and bigger tires then the auto is the way to go. But if you want a tough tranny the STi 6 can't be beat.

Swap info here, some minor adjustments for Baja hardware will be needed: http://forums.nasioc.com/forums/showthr ... ?t=1412230
5050GRIP
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Re: Looking to change over to an Automatic

Post by 5050GRIP »

Thank you for the reply.
You said TCU, as in Traction Control Unit, thought that was part of the ECU/ECM?
Wire harness as in full harness for the engine and dash?
hocrest
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Re: Looking to change over to an Automatic

Post by hocrest »

TCU- Transmission Control Unit

Having done this swap in the other direction, the biggest job will be the wiring. There is a substantial wiring harness that goes along with the AT and the TCU. This harness will not be in a MT car. Rather than trying to make it up, you would be better off getting the bulkhead harness out of a donor. To have a chance of matching up, the donor for the harness would have to be a turbo Baja.

Before you go too far, take a look at the wiring diagram to see what all is going to be involved with swapping in an AT.
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bajaguy
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Re: Looking to change over to an Automatic

Post by bajaguy »

Took my transmission 3 weeks to find what they thought was "the last Baja TCU in the US." Good luck finding one. There are plenty of us that would readily trade an auto for a manual. I just ticked 110K on my 05 auto, what does yours have?
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5050GRIP
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Re: Looking to change over to an Automatic

Post by 5050GRIP »

About 225K, yeah the box is making a sort of gear whining noise while driving, mostly in lower gears, gets more pronounced after it warms up. Difficulty disengaging clutch and syncros in 1,2. I changed the oil twice in the box withing the last 50K. Its barely noticeably at highway speeds but gearing down makes low noise. Started happening when I took a 250m drive without added 4 extra psi to rear tires, while the vehicle was loaded up. Pressure was at 30F, 29R.
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