OBDII to OBD I Transmission Swap Auto

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f22b1 coupe

Junior Member
I have a 96 EX Auto (OBDII) and the tranny has a mild slip only when it's cold in the dead of winter but it still makes me nervous so I bought a parts car, a 94 EX Auto (OBDI). I pulled the motor and sold it, so now I am left with the tranny, and I have a very basic question, is the harness the same? Is the auto tranny the exact same, or was the transmission different in some way mechanically or electronically/with the sensors that will stop me from just putting the new tranny in. And if so, can I just swap sensors/solenoids over off the old case or is it internally different?
 
Unfortunately not. I'm in KY. I'm beginning to think that this swap is not easy enough for me. I just wanted to be able to take one out and put another one straight back in---no changes, no different tcu, ecu, wiring harnesses, etc...
 
Are you in North Kentucky like Louisville, or further than that? I don't know if you'd be interested in trading, but I'd be willing to meet you halfway (assuming you're not in like Ashland or Bowling Green :p) and we would both come out ahead. I'm in Indianapolis, and the tranny has 200k on it (the car was wrecked in the front at 199,996- talk about crappy luck :p). I drove the car home after I bought it before I stripped it down, so I know the tranny was totally fine in it, and a female school teacher was the original and only owner, no mods, so I'm pretty sure the thing was babied bigtime. They had it dealer serviced (ridiculously expensive, but it was perfect for me :p). So assuming you have good reason to believe your transmission will be in A-1 shape as well, and those miles on mine don't scare you, I think we could do each other a pretty big favor.
 
Well I just called my local dealer and they expressed that there should be no issue at all- so we both may be totally fine putting in the ones we've got. See my only concern was that the TCU would be different, I know the ECU is FOR SURE, but that doesn't mean they can't use the same TU, and by extension, the same sensors and components for the transmission. I still would like to have a quantitative way to confirm the compatibility, but they didn't have access to part numbers which was strange.
 
Update: took a gamble and put it in tonight, its super damn late so I am calling it a night, but as far as externals, everything matched up, and mechanically it was a plug and play. The true test will be when I run it through the gears tomorrow, but I took lots of pics as I did it, I'll share those later when I get time.

Note to anyone else swapping trannies, take the time to replace the input shaft seal (on autos you have to slide the torque converter off first). It's not a bad idea either to do the output shaft seals, the seals around where the axles leave the tranny. It's iffy on the seals I got from Auto Zone, one didn't even have the little shroud for the axle built in even though it was Timken. On the output shaft seals, they wanted to slide in much deeper than the OEM ones and I'm afraid they wont match the axles and I'll have a tranny fluid leak. Again, when I turn the key it will be the moment of truth. The input shaft seal was simple enough though, no concerns on it or the rear main, which I cannot emphasize enough, if you are pulling a tranny or engine, take the damn time and money to do your seals!!!

I was pleased that it was only $35 for the input seal, output seals, and rear main, and I will never have to worry about an oil leak that makes me pull the motor or tranny. I am going to do the oil pan gasket while I'm at it, I've got the exhaust off. Hopefully the gasket isn't shellacked on or whatever like the last accord I did. I also caught that my pan was missing a bolt!!! Either it was that way from the factory, or its been done before, both of which seem unlikely. Fortunately I've stripped down two Civic blocks and I had plenty of spare pan bolts around. I've got oil on the back of my block, up around the oil filter, but I know its not the filter or the valve cover gasket, I replaced it when I did the timing belt a couple of years ago. Anyone ever have an oil pressure sending unit start leaking? That's the only other thing in that vicinity, besides the head gasket *GULP* and I really doubt thats it, runs fine, no smoke, no significant oil loss, just messy back side of the block.
 
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My f22a6 was a mess on the back of the block by the filter... I am assuming from oil spilling out of the filter the few times it was changed.
 
UPDATE: Tranny swap went super smooth. So, for everyone else's sake I subjected my car to an experiment and you can indeed interchange OBDI and OBD II Transmissions.

and Jeepcreep, that's what I was thinking, maybe that the oil filters I've bought have cheap seals, because it sprays up even above the filter, and I know my valve cover gasket is new, and properly torqued, so its not leaking down, its leaking up. I did the pan and real main, so now I have replaced every seal on the engine except the seals behind the timing belt, I was an idiot and didn't know how to do that when I did my timing :( So I will some afternoon tear it down and do those 3 in case it's the cam seal, I've seen that one leak down across the back of the block as well. I am a huge fan now of using synthetic, and replacing high mileage oil seals. I use Mobil 1 Extended Performance (the 15,000 mile oil) and over the course of 1 year, I lose 1 quart at 225k on my F22B1. God I love my Accord :). Btw, did the timing belt on my dad's 02 D17 and at 100,000, with him using that oil from the day the oil was first changed, it looked new. Not like new, new. No engine discoloration from the color aluminum should look, no deposits, no anything, new, at 103k miles. I'll post pics sometime.
 
Good to know. I guess I learn something new every day. Thanks for sharing:)
 
I thought it was illegal to go down obds???? What's the significance of that?? Heard you can't pass inspection with an obd lower than what it's supposed to be......or do obds have to do with other things too? Anyone wanna clarify?
 
I thought it was illegal to go down obds???? What's the significance of that?? Heard you can't pass inspection with an obd lower than what it's supposed to be......or do obds have to do with other things too? Anyone wanna clarify?

Illegal hahaha- well if it is in some states, Indiana is not one of them. Someone else will have to answer your question though- like if someone swapped an OBDI H22 into a 97 Accord, when you went to emissions testing I suppose it would be apparent what had been done, but I don't know that it's illegal. I went through a center in Nashville once in a 97 and even with no CEL light on they hooked up and checked, so I'm sure they would notice. Maybe you could explain it away if you had a golden tongue.
 
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