more gearbox/torque converter issue plus coolant loss

[john langrick]

Hi, I have been reading with interest of similar problems and their resolutions.

Xc90 d5 d5 geartronic 2003 160k. Car has been fine until recent long journey 400 miles there and back with four adults and luggage. I started to notice a slight judder between 50 and 60, which I read is when torque converter achieves lock up. I never really notice this judder before.

On the return journey, when cruising about 70mph, there was a slight jerk, after which the transmission service light came on. First time this has happened in my ownership of almost 2 years. I stopped at services and checked around and could see nothing obvious and then continued on my journey.

After another 200 miles, after meeting slower traffic, I noticed that the car appeared to be stuck in 4th ( ie limp mode). I continued to drive, but after about 30 mins of 50mph driving, got the message 'coolant low'. By this time was 10 mins from home where I stopped car. On restarting the gearbox was back to normal (other than transmission service required message) and after topping up coolant header tank which was almost empty.

Checked codes and had TCM error 002f 'lock up function slipping or not engaged'. This cleared by myvteader and all appeared well. Car ran fine for a few weeks but only driven about 20 miles daily, never exceeding 50 mph, but all gears working fine.

I lent son car to take family for a weekend break. Son contacted me when he arrive as he had coolant low message, before setting back, he topped up header tank when returned to me, had almost empty header tank and again error code 002f stored.

My belief is that the torque converter is worn, tho problem occurring when coasting. A very interesting post by 'misspentyouth' being very helpful in his own diagnosis that the two sensors before and after torque converter will generate this message if input varies from output. In his resolution the pipes in gearbox cooler had failed, leaking coolant into the gearbox with resulting problems.

I thought I might have same, but transmission fluid, appears clear, although a tad light browner than red, and is at the correct level and certainly not emulsified, something I would expect if coolant was leaking into it.

Both myself and my local indi have searched for obvious coolant fluid leaks, but cannot see any. This includes all radiator hoses, heater hoses, header tank etc. This was done with engine running (hot) and cold. Also, with local running, no further than 20 miles per day, water level constant, gearbox operating fine.

It appears the loss of water coincides with gearbox limp mode. Does this make sense? Could the water overheat and potentially boil if the gearbox overheats?

Note the engine temp never appears to rise over the normal, which is very slightly over 50% reading. Cooling fan operates similar to all volvos I have owned.

I do plan to get the gearbox and torque converter fixed by a specialist garage. My first quote is between 2 and 2.5k, plus vat. This has 1 year or 12k warranty, which I am prepared to pay. But this coolant loss issue is worrying me more. (Will get more quotes).

I am happy with this car and although it is costing me a lot, my choice is that I am prepared to suffer the cost.

So again, question is, will gearbox limp mode cause such excessive overheating to cause coolant loss?

Many thanks to other members and treads on similar issues which have been helpful, and for reading so far!

[Tannaton]

I believe your problem is almost certainly the radiator has failed and is leaking coolant into the transmission fluid (there is a heat exchanger in the radiator to cool/heat the transmission fluid).

This requires urgent attention, the more you drive it the less of a gearbox will be left.... (if this is in fact the problem).

It may not show up in the transmission fluid as the water can boil off but it will leave the antifreeze behind.

It’s too much of a coincidence to have these symptoms occur at once. - I would get the rad and trans fluid changed ASAP.

[john langrick]

Hi and many thanks for the response. Been on holiday so sorry for the delay. I have car booked in on Tues for pre MOT check and will discuss my plan to order a second hand rad and get my indi to please do a 'Gibson method' on gearbox.

A very useful post (I hope i have the correct name). Let's hope I get away with it. Failing that I have a quote for fully reconditioned gearbox at £1750 which I am prepared to pay.

So thanks again and will post how things progress.

John l

[john langrick]

Hi,
Radiator replaced. I chose a new nissens OEM radiator
I not have nissens ac condenser, aircon pump and now main rad. Very happy with quality.

I could have purchased a second hand rad for about £40, or a complete condenser/rad/fan pack for about £120. As I already have a new condenser, thought best to buy a new rad too.

I also ad a full gearbox flush, rad hose off etc, plus adaptations reset.

When driving around town I never had problems, but I now notice the gearbox (torque converter) seems to lock much quicker at about 60mph. Gears all smooth, but they always were.

Here's Hoping I get away without a gearbox.

[john langrick]

A quick update, 3000 miles later, no coolant loss, no gearbox errors, in fact no errors at all noted.

Just returned from a 1000 mile trip with five adults, aircon on for about 100 miles, mixed driving, Yorkshire moors and exploring towns. Av mpg 42 mpg, no oil use. Av speed 30mph Not bad for a 15 year old car, but I do drive like a nanna.

Or maybe I should not speak to soon!

Johnl

[Harley Dave]

Glad to hear you've got it sorted and great shout from Tannaton

Cheers

Dave