I checked the trans fluid over the wekend, and it is a light brown/pink, so I plan to do a fuill flush. I have three quick questions.

First, I noted the instructions on the faq, but am unclear on what size diametre hose is needed to fit into the dipstick tube.

Second, I understand one should be extremely careful with the trans fittgin where it meets the rad as coolant/trans fluid can mix here. How is this possible and how can I make sure there is no contamination of euither fluid?

Third, I will be putting in cold fluid when the engine will be warm, and the fluid coming out will be of a different volume as a result. Given hot fluid expands I am not sure how to make sure the right amount goes in. Do I measure at the full dipstick marker when hot or cold?

Thoughts appreciated.

The flush was a complete success. Volvo is crazy not to recommend flushing on a regular basis, the fluid was black as dirty engine oil. It took 12 litres to do the flush, although we went did an extra three quarts just to be sure it was clean.

The car is quieter, shifts MUCH more smoothly. A well spent $60.

Thanks for the tips everyone.

IPD sells a tranny flush hose that screws in easily. They also sell a nifty flexible skinny transmission fluid hose funnel.

If a moron like me can do it... anyone can!

I used plastic milk jugs marked with quarts and had my son run the engine until two quarts were flushed out. Then we poured two more quarts of new fluid in.

Just kept it up till we'd added in about 12 quarts of new tranny fluid.

It really is very, very easy to do. Easier than an oil change almost.

The metal transmission line is rigid. (The top one I think ) which way should I push/move the line to the drain bucket? Top or to the passenger side?

Dear 960brickster,

Good p.m. and hope this finds you well. Some answers:

(a) to add trans fluid, I use a funnel, rather than a hose. However, if a funnel's tapered end isn't long enough, I'd guess that 3/8" (10mm) diameter plastic tube will fit in the dipstick tube. I secure the hose to the dipstick tube with lightweight wire.


(b) The transmission lines attach to the in-radiator transmission fluid cooler via two brass fittings, which have an hexagonal base. That allows a wrench to be put on them, to keep them from turning, when the trans line fitting is turned, to loosen it, so that the trans line can be disconnected from the radiator.

If a wrench is not put on the hexagonal base of the radiator fitting, it will turn, when the trans line fitting is turned. If the radiator fitting turns, it will break the seal inside the radiator's transmission fluid cooler. That will ruin the brand new radiator.

The reason: breaking the seal lets coolant get into the transmission fluid (the cooling system is pressurized, which forces coolant into the ATF cooler, if there's a leak in the cooler). Coolant water in the ATF dissolves the glue, that adheres the transmission's clutch-pack facings. Microfibers of clutch material will clog the transmission's fluidways, ruining the transmission.

In short, put an adjustable wrench on the hexagonal fitting on the radiator and hold that wrench absolutely steady. Put another wrench on the transmission line fitting and turn that wrench to disconnect the transmission line from the fitting on the radiator.

(c) The AW30-40 or AW30-43 trannies hold about 8.5 quarts of fluid. Plan on using 10-11 quarts, to be sure to remove all old fluid. As the flush process requires the engine to be running, the incoming fluid will heat up pretty quickly. The volume difference between cold fluid and hot fluid will not be significant.

When you drain the old fluid, use gallon milk bottles. When you have drained two gallons, add a further pint, slowly. This is the difference between MAX from MIN values on the dipstick. Because over-filling means draining fluid from the pan, check the level repeatedly as you add the last pint. Top-up by adding fluid slowly. The trans will not be damaged by being a pint low, the moreso that you'll bring up the level to MAX in a couple of minutes.

Hope this helps.

Yours faithfully,

spook

Thanks for the guidance.

So, the large brass 1" nut is ti be unscrewed, but I need to put a crescent wrench on the fiting closest to the rad. Any idea what size on the part closest to the rad?

What measure of torque is required when tightrening back on? Is there any need for thread treatments?

Regarding removing the line from the radiator.

Long ago I learned this trick. Always use two wrenches. The fitting on the line and the one attached to the radiator usually take different-sized wrenches. They must be either open-end or adjustable or flare wrenches.

This entire rain dance is to avoid exerting any twisting force on the fitting in the radiator against the radiator itself. The metal is thin and, as Spook said, breaking that seal will at min ruin the radiator, plus maybe ruin the tranny, too.

Position the two wrenches so that they form a "V" of 45 degrees or a little less. That way you can get one hand on the "V" and squeeze it together, hard. All force is exerted on the two fittings, none on the fitting-to-rad seal.

Usually with that type of fitting once loosened it is almost finger-loose.

Move the line out of the way gently. When it's time to reattach, it must be perfectly straight-on or the fitting can be easily cross-threaded. When re-attaching, use the "V" system to tighten up.

Once you see how that "V" with two wrenches works, you will use it in many applications. It often makes things easier.

You might get a flare nut wrench for the line fitting. Such a wrench is like a box-end wrench with an opening in the box to slip over the tube. They work very well. Do not attempt to make a flare wrench by cutting a box end wrench. The forged grain structure is too weak to hold. BTDT

Good Luck with the job.

Bob

:>)


PS: Note that using empty gallon jugs is good. I use empty 2 liter cola bottles. A full one is about 2 quarts, so I have a measure. They seal tightly so I can carry them to a recycling place and not worry about leakage if one tumps over.

FYI, It's a 95 960 2.9 l sedan.

Hey Brickster--On the top line for the fitting going back into the rad I went to lowes and found a pipe coupling that was of the thread dia. that had and used a flaired metal tube through the center of it. I cut one side of the flared tubing off and then put the threaded coupler through it with the flared side going to the rad. I then used some jb weild to hold the coupler and pipe together to keep it from sliding back from the flared end. After the jb weild set up--you just take the top fitting off from the rad-insert the fitting you have made and hook a small hose to the back and empty in milk jugs or what ever-I used a 5 gall bucket marked with two qrt marks inside the bucket. Follow all the work listed above and it's easy as pie. When the fluid starts coming out cherry red you'll be there.