Question about transmission flush method

Pezgoon · Post by **Pezgoon** » 18 Jun 2016, 07:52

Hey there, so I've read the methods and a few posts about it but I didn't see anyone ask a seemingly obvious question to me. Why wouldn't you want to disconnect the lower radiator hose (return) put the tubing on the radiator and flush the cooling section as well

The oil cooler is gonna be full of sht too, and if the return line is not a suction line and its a pressure fed system only from the feed line then the old fluid will only be somewhat gravity fed into the transmission and then will get no new fluid circulating through to clean it out (since the feed is disconnected)

So why wouldn't you want to do it on the return portion of the cooler to power clean the ENTIRE system rather than just the transmission?

Am I missing something?

Also would it be possible to get two hoses and disconnect it on the return and have it from the cooler dumping into a container and then run another hose to the return line, hold it way up with a funnel and pour it into there? I know it has no suction but with the gravity feed do you think it would do a complete circuit? Similar to putting the return hose into the quarts and sucking them up

Thanks

Post by **scot850** » 18 Jun 2016, 07:59

The answer is yes I guess to your question. You could remove both lines and gravity feed the fluid down into the radiator cooler. Keeping the system clean with fresh fluid is the secret. That is why some guys drain and fill the system with fresh fluid each oil change. Overkill in my opinion. As long as you don't power flush you should be ok. The other thing is radiators have a finite life, so chances are you will change it as often as your transmission flushes.

Neil

Pezgoon · Post by **Pezgoon** » 18 Jun 2016, 08:16

What is the average life we get out of these radiators?

BTW its a 93 850 with 71k on it

I have to do the fluid as its 23 years old and the car has been essentially sitting for the last 5 years being driven once every few months

My biggest concern is the moisture that is in the tranny from it not being driven, so by not flushing the cooler with it I am concerned about the old fluid being full of moisture still sitting in there, and even any of the suspended particles in the old fluid just continuing to circulate through the tranny.

Is there anything wrong with disconnecting the return line on the radiator and doing the regular flush technique at that point in the system rather than the feed line? So that it is flushed out at the same time as the rest of it?

I know you say that the radiator is replaced at the same time but some people do their flush every 30k, I've never heard of a radiator lasting only 30k...

My 23 year old one still looks great, but I'm sure it may not look so great on the inside

So I'm really just curious as to why no one flushes the cooler at the same time, regardless of whether the radiator is replaced or not? If there is no suction on the return to the tranny then that means the old fluid is always gonna be in the cooler, at least in some amount.

Food for thought?

Post by **oragex** » 18 Jun 2016, 08:44

didn't put the correct fluid depending on the transmission and also you no need to drain the pan, just with the return line is enough. This will flush the transmission pan, the torque converter and the transmission cooler (inside the engine radiator) all together.

Pezgoon wrote:Hey there, so I've read the methods and a few posts about it but I didn't see anyone ask a seemingly obvious question to me. Why wouldn't you want to disconnect the lower radiator hose (return) put the tubing on the radiator and flush the cooling section as well

Lower line is outgoing, upper one is the return line - is why he's placing the plastic tube on the radiator side instead of the transmission line side, the fluid will be flowing out of the radiator.

The lower outgoing line has the same connection but on my 13yrs old S60 is so badly corroded, I'd be afraid to remove it from there.

Pezgoon · Post by **Pezgoon** » 18 Jun 2016, 11:03

Oh okay, I was reading the modified transmission flush on here and it was the opposite so it caused me alittle confusion, I may still drain the pan just in case anything has collected in it over the years otherwise that is how i will do it.

I got the Valvoline max life full synthetic, it meets the volvo standard and 50$ for 12 qts vs 120 for mobil 1 was a much better deal for me especially right now with the car how it is

Post by **oragex** » 18 Jun 2016, 13:03

Thinking, draining the pan is a good idea because it has a magnetic plug so you get the occasion to clean it nicely.

My advice, don't go Valvoline MaxLife. I had it and didn't like how it shifted on cold engine in cold winter mornings - and you don't seem geographically located too far away. But what put me off the most was the fluid expansion with temperature. Basically, I could not get dipstick proper reading with this fluid, in summer it was showing hot level and ever higher at fully warmed up, in cold winter I had a few times when the car would not advance in D because the fluid was too low.

I also had the Mobil 1 3309, it seems a little 'light'. The one I like the most is the Toyota Type 4. Now, people will comment these fluids are all the same, but I respectfully disagree. They are all 3309 fluids, but the other components are not in the same volume. Toyota Type 4 is sold by a main dealer - I believe the larger in the world, and Toyota has several vehicles with the same Aisin transmission as Volvo.

Post by **erikv11** » 19 Jun 2016, 05:28

I use cheap fluid, SuperTech Dex 3 from Walmart. Along the same lines, I think flushing the cooler is overkill. Once you do a 14 qt flow-through flush, drain and fill the pan every 30k. That's working great for all my Volvos, including in Iowa winters.

Radiator life is superb if you buy the Volvo branded one, I will speculate it is reasonable to expect a minimum of 10 years. I've never had to replace a radiator more than once, but I've only bought them from Volvo. The oldest one I have is from 2006, I first put that part in the car I wrecked now it is in my S70. The other brands seem to last a year or two at the worst, or run trouble-free at the best.

Pezgoon · Post by **Pezgoon** » 19 Jun 2016, 09:13

Erikv11, this is interesting to me, if they only last about 10 years what is it that makes you replace them? I see nothing wrong with mine and I had to have a brake line changed which I had a mechanic do it O_O

While it was there my father asked him to change the coolant as well which I partially wasnt happy about as I have to still do all the hoses so I didn't see if any crap came out with the coolant. The radiator in the beast is the original one so its 23 years old, it only has 71k on it though and it seems to have no leaks at all and certainly looks better than everything attached to it. Should I be concerned with its current state?

No issues with the supertech? I was considering it but I wanted synthetic and they didn't have any at mine so I went with the valvoline and the valvoline listed not only that it met every manufactures guidlines but that it met three of volvos so I went with it.

At this point I don't care that much because I have yet to drive the thing longer than five fckin minutes. I want the thing on the road so I can see if its even worth driving and all this work I've done

Post by **scot850** » 19 Jun 2016, 23:17

The problem with the radiators is they use plastic end caps attached to aluminum core. The plastic decays and goes brittle with age. The engine can move a lot and it tends to strain the top hose attachment point and it can sheer off, or the radiator cracks at the join between the plastic and aluminum, for me this is also on the same side as the upper hose (RH side). Life span can be also dependant on the torque bushes and engine mounts. So there is no magic number of years, but I'd agree 10 + years is good, and I also use Volvo only. Keep an eye on it and watch for dampness at the joints either side. Also suggest it is worth squirting penetrating oil on the 2 lower radiator bolts from time to time to prevent them rusting and snapping the captured nuts off when you do have to remove the radiator.

Neil.

Pezgoon · Post by **Pezgoon** » 21 Jun 2016, 07:23

Will do thanks, I did notice dampness where the lower transmission line attaches but the coolant level was normal so I'm not sure if ita coolant or transmission fluid ( I think it may have been that but I didn't measure before doing the flush

Oragex I thought the dexron 2 and mobil1 3309 were NOT interchangeable? Mine requires dexron 2 and since that's more of a basic atf I will probably have better luck than you with the max life, we shall see anyways.

Also I see why no one does the return, there was no way for getting to it without taking the battery tray out so I just did it the normal way at the top hose