Having just finished a timing belt job, front seals and new breather box I felt ready to challenge my first rear main seal. I also decided that this would be a great time to upgrade to an AW71L with a roller bearing tail shaft. Off to the pick and pull to see what was available. There were a couple of 940’s with around 150K on the odometer. To be honest I really didn’t want to have to yank a 150lb transmission on my back. A couple of rows down I spotted a green 1994 940 with 84K on the odometer with a missing transmission and engine. I grabbed another 946 EGR ECU that I didn't need and headed out. At the counter I asked about the tranny from the green 940. The guy said yeah we sold the engine a few days ago and you can have the transmission for 150. (I’m a loyal customer at this yard) I don’t have to tell you guys that I felt like a kid in a candy store. The following morning I went back to pick up it up. Once home it spent a week on the bench. First I drained the fluid and cleaned the sediment inside the pan. 3 pan bolts snapped (IMHO Swedish steel is better than Japanese) so I had to purchase some cobalt drill bits on EBAY to drill and re-tap. This took some time but went ok. I also replaced the bolts on the overdrive solenoid. One broke but managed to get it out with vise grips. Also replaced the front seal and the shifter seals. Once on the lift I started to pull my original transmission. I took my time and didn’t run into any problems. I have an air gun I used to remove the transmission bolts. I also removed the complete exhaust system from front pipe back. The rear main seal was genuine Volvo from Tasca. ($ 17) I used Mobil 1 grease on all the seals. Installed the rear main approximately 3mm deeper than before. With the transmission out I undercoated the tunnel with 2 cans 3M rubberized undercoating. (6.99 can at Wal-Mart) I really like this stuff and the noise reduction was significant. Remember Volvo can’t really access the tunnel when they undercoat. I also removed the rear muffler guard. There was some corrosion from the dissimilar metals of the guard and the chassis. I used a dremel to remove the rust and applied 2 coats of POR 15. After the POR dried I sprayed another 2 cans of 3M undercoating in the area under the muffler guard. Here again the noise reduction was significant. My front pipe was rusty and the front support bracket was rusted off so I replaced with a SS Miller down pipe. It was $168 from eEuro and is made with T409 stainless steel. It was lighter than the original and I have yet to issue a quality verdict on it. My original EGR cat(very large)was supper clean inside and decided to reuse it. The spin flange bolts where seized inside so I had to cut and drill them out. After this I sanded it and painted it with Barbeque paint. I used a cheap HF single stage transmission jack to remove and install the transmission. It was a grunt to get the transmission up on the jack as its just a single stage. No major problems putting every thing back together. I used loctite on the flywheel bolts and torqued to spec. The transmission lines were frozen at the transmission so I cut them replaced the ends with some non-frozen ones and spliced them in with 5/16” compression fittings. After everything was back together I changed and flushed the fluid with 3 gallons of Super Tech ATF fluid from Wal-Mart. It took 2 test drives before I noticed the actual shift into overdrive. It happens at slightly less than 50 and is pretty sutle. Overall I’m really happy. The transmission shifts very nicely and much better than the orginal. The engine noise on the highway is noticeably less and MPG should go up. I purchased a 5/16” Magnefine filter on EBAY and will install it after the next fluid flush shortly. At that time I will also change to synthetic. Is an oil cooler is worthwhile? Who says old Volvo’s don’t get better with age.