2002 V70 XC Transmission problem(s)

philbrooksjazz · Post by **philbrooksjazz** » 15 Sep 2014, 03:15

Here is a short history of my problem

1. 2002 V70 XC, Aisin Warner aw55-50sn transmission - 92K
2. June 2014 - Crack in Radiator - coolant and trans fluid mixed badly
3. Next day, Radiator replaced - tranny and coolant flushed - driving OK
4. Sep 7th, car stopped moving, 'transmission service required' message on. (0700 & 0740 codes)
5. Next day, I tried flushing the transmission, this seemed to work, car driving OK for 6 days.
6. Today, same problem is back, I tried adding some additional fluid, car drove until the transmission warmed up, then same issue. 'transmission service urgent' message on.

The problem starts with the transmission jumping between gears, then no power to wheels. It seems like it happens when I have to drive the car very slowly (< 25 mph) on a hot day. I'm praying that it might be a fluid problem, or possibly an issue where the fluid isn't cooling correctly.

When I flushed the transmission, the fluid was quite milky - not clear like it should be. I fear there is still quite a bit of water in there from the radiator issue. But it clearly seems to work much better when cold. I'm going to try and take it to a transmission shop and get a full drain / flush, to see if that helps.

I know there is much info here about 01-02 V70 transmission problems, can anyone tell me the exact nature of the failure?

Thanks very much,
Phil

Post by **oragex** » 15 Sep 2014, 17:40

The 01-02 transmission problems are not the one you have (although cracked transmission cooler is pretty common as well).

What I think is happening, is the transmission fluid is overheating - giving the service message.

An important thing, make sure the radiator fan is kicking in at high speed, particularly when the transmission starts acting up. The fan has to cool down the engine coolant, the A/C evaporator and also the transmission fluid that is passing through the radiator.

When flushing the transmission, was all the fluid replaced by disconnecting the upper hose while running the transmission - while adding fresh fluid by the dipstick tube? This way all the contaminated fluid is removed. That said, not sure if a transmission can be really totally 'cleaned' once contaminated.

I would also try Valvoline Max Life, some people say it got better results that the regular 3309 fluid, being fully synthetic. In all cases, if the fluid is overheating, it has lost it's properties and it needs replaced.

Post by **JRL** » 16 Sep 2014, 07:56

If the fluids mixed the transmission is HISTORY, PERIOD

philbrooksjazz · Post by **philbrooksjazz** » 16 Sep 2014, 13:03

oragex,

Thanks very much for the info - yes I think the issue is that the fluid is overheating. As to the flush method, that's how I did it, pull the top connector off of the radiator, connect a hose, turn on the engine and let the internal pump fill a container. Then add new fluid into the dipstick hole. I am using the Valvoline Max Life.
There is no indication the engine is getting hot, and the fan seems to be running correctly - all I can think of is that the replacement radiator / heat exchanger is bad or clogged. Is there a sensor that monitors this?

Post by **precopster** » 16 Sep 2014, 15:17

To flush this transmision properly you would need to drain and fill at LEAST 5 TIMES with consecutive drives between each flush to further mix the coolant around.

Pumping the fluid from the top hose would only retrieve the fluid from one (a relatively high) section of the transmission. If there's water/coolant it will settle in the lowest part of the transmission which has a mesh filter. This filter is only retrievable upon full disassembly. The drain plug is lowest on the transmission and would tend to have the most coolant/water content.

luckycharms · Post by **luckycharms** » 29 Sep 2014, 02:06

Im just replaced my transmission with a know good one. Its acting similar. I used the valvoline max life. It drove fine for a couple of days.But,now after driving approximately 50 miles total over a 3 day period, the fluid is black and smells burnt.

ChiNorm · Post by **ChiNorm** » 29 Sep 2014, 12:41

Are you sure that the Valvoline ATF meets the Volvo requirements?

Good luck.

luckycharms · Post by **luckycharms** » 29 Sep 2014, 13:14

The bottle says it does and ther are several posts here saying theyve had great results.

luckycharms · Post by **luckycharms** » 29 Sep 2014, 13:29

The radiator was leaking and the car got hot. Does the TCM somehow sense the transmission fluid overheating and lockout the solenoids?

Post by **vtl** » 29 Sep 2014, 14:54

You absolutely need to reset transmission adaptation after any major work done on transmission and run it through relearn procedure.