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I have a 98 civic ex coupe, auto trans is the B4RA.

My second trans broke yesterday (third for the car, second for me), both broke from having backwards momentum while shifting into drive and applying throttle. It won't go into any gear (reverse, D4, D3, or 2) and when I try I hear a bad clunking and feel grinding.

My question is that I would like to know what part of my trans that I broke so I can try and rebuild it. The first time it happened I decided just to do a swap with one from the junkyard, it worked great for a year until it broke the same way the first one did. My plan is to try and figure out what broke and attempt to rebuild the trans myself.
Any insight would be appreciated, also if you know of any good rebuild walkthroughs (or videos) for this trans I would be thankful. I tried finding some last time this happened and couldn't find a video for this specific trans.
Thanks

 
Rep Power: 222

Don't shift into drive and give it gas while rolling backwards, that's how you keep breaking them

 
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Thanks for responding Colin
Though, I was already aware of that.

Neither time that it broke was there extreme backwards force put on the trans, the first time it happened I did it on a slight backwards incline while going from reverse to drive (I wasn't aware how sensitive the trans is) and I was barely moving backwards still.
The second time was when my wife was driving, and I'll have to slightly correct my first post, it wasn't while switching gears but while she was in drive and sitting in traffic on a hill where road construction was ahead. She had her foot on the brake until she was ready to go and just from switching from brake to gas while on a hill was enough to break this trans. That one had worked for a year with no problems, I drove it a LOT and it worked great.
I think it must be a bad design, I've never heard of this kind of failure before, and I can't find anything on this specific symptom in a Google search

 
Rep Power: 222

I've owned 4 of these 6th gens that were automatics and I never had any problems with them and 3 of the 4 were sub $1000 beaters. You'll have to pull the case apart to see what is actually broken. You could try getting a Japanese imported used trans, they're supposed to low mileage. Or try a junkyard again. Or local buy and sell

 
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I applaud that you want to rebuild this yourself. It's a pretty serious job to take these apart and replace all the clutch packs and such. You might not find it cost effective to fix vs buy another one. However, if you do, take a look at something like this rebuild video to get some idea of how much work this is going to be:
In addition, I think I've heard the best kit was the TCI master rebuild kit. If you do rebuild it, post some pics, this is not the easiest job and hard to find a DIY.