I've read the other posts, but thought I'd ask one more time. Is there a return line I can remove to the transmission and cycle the motor on and off to "push" out say a gallon of fluid each time the engine is started, turn off, refill the transmission, and do over?

I've used this method with a powerstroke diesel to change all the fluid at once. I removed the cooler line at the radiator, put a piece of tube on the return line and put it into a gallon jug. With a helper, we cycled the engine on until the jug was filled. Shut off and re-filled the transmission and did again until 3 full jugs of "old" fluid.

Is there such a return line on the Discovery SD? Is it possible to use low pressure air from an air compressor to blow air into the line removed from the front of the transmission pan to "push" the remaining fluid through?

I've already dropped the pan and changed the filter. Pan looked really good, but the fluid is somewhat brown so I'd like to change it all. I know I can change about a gallon at a time, but it will take me many drains to dilute the old fluid well enough for my liking.

Thanks for your help.

 

The tranny cooler line is there, plus there is a pressure test point on the bottom side. Both are shown in the RAVE. I did the same with my Kia minvan, but only did 2 quarts at a time.

 

Would you be able to describe where to remove the line? It looks like some pieces under the radiator need to be removed to access the lines there.

Where is the test port located on the tranny. Will return fluid come out there or is fresh fluid picked up first and discharged there?

I'm assuming that the air compressor thing does not work for either of these.

Do you have any pictures of the cooler line or the test port?

Thanks.

I do not have the RAVE.

 

Well now, another potential student of my favorite "Brit Lit". Follow links in my signature and you can download all of the RAVE for free.

I would point out that if fluid is dark, and shows particles when you wipe the dip stick on a clean white paper towel; those particles come mainly from one source, the clutch disks. If a smell like a burned coffee pot is there, then tranny work could be in your future.

The quantity of fluid trapped in the torque converter does not come out on a simple drain, so people usually have to drain and refill like three times, with short use inbetween and cycle manually thru all gears.

Heres a detail on the tranny cooler lines, they are on the driver side of the radiator, loop under to a "towel bar" on front of radiator. Lines on battery side are the oil cooler for engine. O rings in all of them. Also here are some pages on the tranny test port (high pressure 100 - 150 PSI), and what is involved to get at the filter (for others going down this trail).

After looking this over, and the rest of it in the RAVE workshop manual, you may decide a trip to a shop, like one that sells the BG products, for a machine connected flush might be in order.

 

ok stupid question, why is it that the top trans line in the pdf runs under the center of the rad to the remote cooler but the one on my d1 runs around through the left wheel well for rocks and debris to hit it and rot it out?

also this has no torque converter drain plug?

 

My 97 is pretty much like the RAVE, but it is away at college and I only see it on weekends, can't go peek. No drain on TC.

 

my line is rusted real bad so I grabbed the lines off the 95/96 I got the springs from in the jy and that line still runs through the wheel well, it is the shortest distance between those 2 coolers but a horrible location probly saved LR .20 by making the line shorter

 

Downloaded the RAVE. Great stuff, thank you.

Looks like I'm going to just get a case of Dextron III and start rotating it through until it's clean unless someone has a FAQ with pictures to tell me exactly where to disconnect the return/cooler line? It sounds like from your last post you have done this procedure before. I'm just a bit ignorant on this procedure. Now if it is a Ford F350 Powerstroke, I could help you there.

Can you tell me if Mobil 1 synthetic ATF meets the specs for Dextron III ?

If it does, I'll flush it out with cheapest and then buy the mobile 1 and finish the flush.

$10 a quart for mobile 1, $15 a quart for the Pentosin ATF is a bit pricy.

Thanks.

 

I've not done it on my D1, have done it on other vehicles. Have taken the rad in/out of D1 several times, the tranny cooler fittings have O-rings. Whichever line is cooler is the return line. You would need to force some clear tubing over the fittings to hit the drain bucket. That lets you see the color coming out. I'll let others comment on just refill a quart at a time thru dip stick, or rig up a funnel on the return line. With the dipstick re-fill, I know it is going into the sump.

Mobile 1 is fine, see ATF | Mobil 1™ Synthetic ATF#

What ever you flush it with will still be in the torque converter. I flushed my van until it came out looking new, then two more quarts.