96 Civic LX 5 speed. I parked the new civic, found a rather large spot under it in the morning. Looks like trans fluid. Looked underneath and noticed a lot of wet around the oil pan. Where the transmission and the engine mate up looks to be where it mates up.

I'm assuming the PO let this go on for a while, and might be related to the noise I get on deceleration in first/second (noise on deceleration Youtube post).

I don't see any easy way of checking that seal. I have heard a transmission swap isn't too bad a deal, if I have to pay someone $500 to change a seal, I might just buy a rebuilt for $500.

 

Given the age and depending on the mileage, it's possible that it's oil from the rear main seal.

 

Check the transmission fluid level (transmission is filled with either Honda Manual Transmission Fluid, or motor oil, not heavy gear oil). You have to unscrew the plug on the outside back to check it. The plug is behind where the right side CV axle goes in.

Also check the engine oil level. Clean the oil off and watch closely for where it comes out. If it came out of the engine it is typically dark or black. The stuff in the transmission would be like new motor oil.

 

The leak is clear fluid. And yeah, the leak area looks to be the rear main seal. I didn't know if that was still called that on these 'sideways' engines.

 

Anyone have a link to a transmission replacement walkthrough? Having trouble finding any on the internet.