Faithful 2002 Honda Civic Issues

I have a 2002 Honda Civic with about 167,000 original miles, I had my transmission rebuild about two months ago. Two things happened after: 1. The engine started to heat up. 2. Started to loose coolant for no reason. Well, after adding and driving for 8 weeks it stop losing coolant and cool to normal. Today I got a surprise on my way to school and work. It has started to over heat and the transmission is slipping on the 3rd gear. I do drive about 100 miles every day as I commute to work. Any ideas to start up on the easy fixes?
Thanks!
Emilio.

My first guess would be that they messed up the radiator when they disconnected or reconnected the transmission fluid lines that lead to and from the radiator. Of course, on a car this old, you might just need a new radiator. The passages might be clogged.

My second guess would be that you got a defective rebuilt transmission. It happens.

Is your transmission fluid at the correct level and color? I’m wondering if coolant is leaking into the transmission fluid due to a problem in the radiator.

These are good questions and answers for me. The transmission placed said that they added more coolant to the radiator and it was back to normal driving. I’m a bit skeptical about it. I’m not mechanically inclined and now going to a second shop for a second opinion is going to increase my cost. I appreciate any of your comments. I"m not ready to give up on this car yet.

Getting a second opinion might be costly, but not as costly as a new transmission or a new engine … or a new car. Sometimes you have to bite the bullet and pay for a second opinion. In fact, you might be better off with a second shop. Think about it; if the first shop messed something up, they have a conflict of interest in hiding it or making you pay for it. You need an unbiased opinion and the next shop might be better (and more trustworthy) than the first.

The slipping in 3rd gear must be transmission related and may not be related to dropping coolant levels. Replacing the radiator is not hard (check YouTube) on Civics and they are relatively cheap.