New Modified Transmission Flush Method with Pictures

MadeInJapan » Disclaimer
I am adding this typical cover our A$$ stuff: Neither myself, nor anyone else associated with this thread including Matt or MVS are responsible for Any Issue related to this flush. Do this at your own risk.

New Modified Transmission Flush Method with Pictures

Important- Please Read This First (Info for P2 Cars):
I need to add this information at the very beginning of this write up so that there’s no confusion. What is outlined below is for all AWD/FWD Volvo’s up until the design was changed for Volvo P2 cars (’01 and later), but the method is really the same. What is different is that the newer (P2- or ’01 on) Volvo’s transmission fluid flows in the opposite direction. In other words, when you take the tanny-to-radiator line off, you actually let the tranny flush out of the upper hose connection on the radiator with the newer Volvo’s unlike what is written below (therefore you’ll have to get clear tubing that has an outside diameter of 3/4 inch that goes INTO the ATF cooler on the radiator, unlike what is said below of a 1/2 inch inside diameter hose for pre ’01 70 series and 850’s), which shows the hose still connected to the trannyhose itself (earlier than ’01 Volvo’s).

If you have a newer Volvo and don’t do this, you’ll make a mess as fluid will come flowing out of the top of the radiator. Several people on other boards have experienced this and were quite surprised (especially since IPD’s instructions were wrong too). Volvo actually recommends for the P2’s to take the hose off at the tranny, plug the tranny hole with a plastic stopper, and drain from the hose still attached to the radiator (which makes sense but the tranny hole is a biatch to reach). To disconnect the upper hose on the P2 cars, grab the green clamps on each side of the black hose, push in and then pull out. To reinsert, just pinch the clamps again and push the hose in as far as it will go and then release the tabs. For good measure, pull on the hose without pushing in the tabs to make sure it’s secure. It’s actually much easier on these later cars than on the older ones. You can get a case of the Mobil-3309 ATF fluid (JWS-3309 fluid must be used on Aisin Warner 5 speed automatic transmissions and not Dexron III) here at a great savings: http://store.avlube.com/mobilatf3309.html

dasapir originally posted with questions about the transmission flush. After posting back and forth with him he tried a modified flush that I have been wanting to do with my car. After this he sent me an email with his write-up and pictures. I thought it was really excellent and want to add this to the maitenance section. I know that there are at least 3 or maybe even 4 other methods posted, but this is to me the most thorough. Very little is changed from what Dan wrote me. It is below in its entirety.
-MIJ

Volvo Transmission Flush Procedure

1.) The tools required are few: Along neck funnel to access and reach the dipstick and transmission filler tube, a 15/16 or 24mm box/open end (not a 1/2″ drive ratchet since it will not fit between the drain plug and the rear brake fluid lines), 5-6 feet of 1/2″ I.D. clear tubing (5/8″ID will be too wide), snap-ring pliers, and a 6″ electric zip or cable tie for added security after replacing the transmission line clip when you are finished. In addition, a new crush washer for the ATF drain plug (same size as the oil drain plug) and a drain pan will be needed.

tools: Long-neck funnel, 24mm or 15/16″ box/open end, 5-6′ 1/2″ ID clear plastic tubing, snap-ring pliers:

drain pan

2.) Prepare 3 gallon milk jugs marked in 1/2 quart intervals. When flushing the delineations will simplify the process by allowing you to see exactly when to turn off the engine to stop the flow of transmission fluid. If you have an assistant watching the containers and telling when to turn off the engine it will make the job much easier. If not that is why there are 6′ of clear plastic tubing. You will then be able to place the milk jug by the driver-side door and can watch when you are at 2 quart intervals. I used Mobil 1 synthetic ATF. 10 quarts will make a good flush, though you could use 9 and be satisfied.

3.) Place the care on ramps and remember to place the parking brake and blocks behind the rear wheels. The engine should be warm and you should have run through all the gears so the dirt and particles in the ATF is now in suspension. A light for working under the car will also be necessary.

4.) Next you will need to crawl under the car and locate the ATF drain plug. It is located on the driver’s-side behind the front axle. The 2 rear wheel brake-fluid lines run in front and along side. Using the 15/16″ or 24mm box wrench undo the drain plug and drain the transmission fluid into the drain pan.

After the ATF fluid is finished draining replace the drain plug with a new crush washer. Since the drain plug is magnetic, you can examine it for metal particles. prior to replacing it. In any case, it should be cleaned off from sludge and/or metal partcles. Now pour the ATF fluid into one of the pre-marked plastic gallon milk jugs and measure the total amount which was drained. This should between 3-4 quarts. Mine drained 3.25 quarts

ATF drain plug on the driver’s-side. Do not confuse with the oil pan drain plug.

Drain plug looking up with the rear wheel brake-fluid lines running past. It is these 2 lines which prevent accessing the drain plug with a 1/2 inch ratchet. The space is too tight.

5.) Next locate the transmission dipstick/filler-tube. It is located up front on the driver’s-side behind the radiator and between the air intake tube and the covering on the throttle body. The car battery is on the outside toward the wheel. Kinda hidden from view. The transmission dipstick has a yellow handle.

ATF dipstick/ filler-tube. View looking down and toward front of car.

View of ATF dipstick/filler-tube looking from center toward battery side.

6.) Locate the top automatic transmission fluid line coming from the transmission and going to the radiator. This is located on the driver’s side upper outer side of the radiator right next to the battery. In order to remove the line, it is first necessary to pry open the clip holding the line in place. For this you will need the snap-ring pliers. The tips should be placed in the two grooves seen in the picture below. Open the clip by closing the snap-ring pliers, thus spreading open the clip. Remove the clip. Next disconnect the ATF line from the radiator by pulling it straight away.

Transmission fluid line connector driver-side top of radiator. The ATF fluid goes from the transmission to the radiator through this line.

Showing how the snap-ring pliers fit into the transmission connector retaining clip for removal.

7.) At this point the 1/2″ ID clear plastic tubing will need to connected to the transmission fluid line coming from the transmission. The tubing will fit snugly so there is no need for electric zip or cable ties. Do NOT connect the tubing to the nipple on the radiator. Remember, the fluid is coming from the transmission via the line to the radiator, where it will be cooled. You will be draining the ATF from this line. If you connect to the nipple on the radiator, you will have a lot of fluid running out of the line on to the floor and a big mess.

1/2″ ID 5-6′ clear plastic line connected to transmission fluid line coming from the transmission. It should be clear
so you will be able to see the fluid running through the line.

Now comes the part where you will begin the flush. First you will need to replace exactly the same amount of the old ATF which was drained from the transmission pan through the drain plug with new clean transmission fluid. Refill the new ATF through the transmission dipstick/ filler-tube using the long neck funnel. If 3.5 quarts of old fluid was drained when then you will need to refill the pan with 3.5 quarts of new clean ATF. Be sure not to over-fill!

9. Next run the 1/2″ ID clear plastic tube, which is connected to the transmission line, into another pre-marked plastic gallon jug. If you are lucky enough to have an assistant, as I did, to hold the jug and watch the ATF, great, otherwise place the jug near the driver-side door so you can watch it being filled when the engine and transmission are running. Place the car in park. Turn on the car and while the engine is running and with your foot on the brake run through the gears; park, drive, 1st, 2nd, 3rd. Old dirty ATF will start to flow through the line into the plastic milk jug.

Run the engine until approximately 2 quarts have been pumped out or when air bubbles are visible in the hose, then turn off the engine. Now add exactly the same amount of clean new ATF to the transmission via filler tube that was pumped out from the transmission line. Again remember, do not over-fill.

Repeat this procedure for at least a total of 4 cycles (8 quarts) or until the transmission fluid being pumped out of the line becomes a clean red color, indicating that the majority of the fluid in the system has been flushed with new clean fluid (it may take up to 5 cycles). This will take anywhere from 8-10 quarts of ATF to added for replacement from the old ATF pumped from the line and another 3-4 quarts of new ATF replaced from that originally drained from the transmission pan. So, actually a total of about 12-14 quarts of new ATF will have been used.

Clear plastic line in pre-marked gallon milk jug ready to go.

Plastic milk jug with old dirty-brown transmission fluid.

Disconnect the clear plastic tube from the transmission line and reconnect the line to the radiator nipple. Replace the connector clip and for peace of mind, put an electric zip or cable tie around the clip, ensuring it will not pop off. Drive the car off the ramps and on to level ground to check the transmission fluid level according to the owner’s manual. If it everything was done properly, replacing exactly the same amount old fluid with new, the ATF fluid level should be correct. If, per chance, it is too low you can add in small increments. However, if there is too much ATF fluid and it is over the max line the excess will need to be removed. This will require disconnecting the line again and running the engine until about 1/2 quart is removed and again rechecking, etc., etc. That is why it is important to be careful in your measurements. Better a little less, than too much.
Congratulations on a job well done.

Reconnected transmission line with electric zip tie around connector clip.

New Modified Transmission Flush Method with Pictures