Is it the cold weather?

[mr tickle]

On a few occasions since the cold weather started I have been having gearbox slip if I drive up the very steep hill my house is on when the car is cold.
The first few times I was able to continue but only just making it up.

This morning it was slipping so much that I came to a stop as it was slipping fully. I had to turn off the engine for 30 seconds and start again. The initial set off on the hill was then quite good for a few seconds and then began to slip again. I had to stop the car 3 times to make it up.

The box works perfectly when warm with nice smooth changes and I've had no other issues with it other than slip in the last few weeks when cold starting up this hill.

I changed the box oil 6 months ago doing a fill and dump (4 times) and it was also changed when the garage replaced my EGR cooler 3 months ago with the correct volvo sourced oil (I purchased it myself) plus the gearbox software was reset to show oil change.

Could it be that the oil level is a little low (oil tips towards back off the box, not enough oil so it loses drive)?
Or is this a system design in the software to protect the box in very cold weather?
Or could i have another issue?

On the weekend I will check the oil level again in case its low (or high)

2014 XC90 - D5 108k miles autobox.

Many thanks.

[john langrick]

Can you stlll use manually? (Knob to the left).

Cheers

[mr tickle]

Originally Posted by john langrick

Can you stlll use manually? (Knob to the left).

Cheers

I'll try manual 1st gear tomorrow morning

[Tannaton]

When the gearbox fluid is cold the operating profile is changed - there is no torque converter lock-up until you reach circa 60 mph and the shift points are raised. The faster revving and more TC slip is deliberate to get the engine and gearbox up to operating temperature as quickly as possible. However I wouldn't expect it to make the car un-drivable or be significantly different from last year?

Trying the manual mode is a good suggestion, you should still have TC lockup when cold.

[mr tickle]

This morning I tried the hill, in D it began to slip and then I switched over to M where it was still slipping in 2nd and 1st. It always makes it up the first 500 yards or so and it only begins to start to slip when you reach the most steep part. Switching off for 15 seconds or so and re-starting fixes the slip and it will begin normally without slip.

The logical explanation that i have come to is is that because its very cold and the hill is very steep the GB oil can't get around the box in time to give continuous fluid to the compression side(sucking air into the oil pickup tube?). In effect it's similar to the symptoms you would get if you box oil level was low. Could it be similar to race cars that need either dry sumps or baffles to stop the engine oil starvation due to high speed cornering

If I do the hill when warn I have no issues, and it has no problem pulling my boat up it too when warm.

So my options are:

Do nothing and warm the engine up a few minutes before attempting the hill.
Go the long way around
Deliberately over fill the box (probably not a good idea i won't be doing)
Use a thinner oil (Also won't be doing) I'm already using 3324 which isthinner
Buy a manual (also wont be doing, the wife loves this car)

I will be doing option 1 for now.

Like I said in an earlier post I don't think I have a fault with the box, I think its just the effect of very cold and very steep. I will check the level this weekend though to be sure.

Does anyone else live on a very steep hill?

[S60D5-185]

I would check the gearbox fluid level before doing anything else.

It's very easy to do and plenty of videos available. I'm just wondering if the garage have done the last refill and fluid level check correctly.

From memory, the box needs to be up to correct temp and the engine must be running when checking level on that gearbox.

There is a fault that needs sorting.

[Clan]

Originally Posted by mr tickle

I'll try manual 1st gear tomorrow morning

have you got the latest gearbox software ? also check for oil level when running, which model gearbox is it?

[mr tickle]

Originally Posted by Clan

have you got the latest gearbox software ? also check for oil level when running, which model gearbox is it?

I assume a TF80 being the last XC90 year made(2014)
I will do the level check when running and when at the correct temperature.
The car was last serviced at volvo in March 2020. Would they always apply any software updates as routine on a service?

I've done a bit of googling on autos and steep inclines. There are a few websites where they do talk about trannies "going dry" on steep climbs.
To be sure I'll check my levels myself - the garage did it last (not volvo).

[Clan]

Originally Posted by mr tickle

I assume a TF80 being the last XC90 year made(2014)
I will do the level check when running and when at the correct temperature.
The car was last serviced at volvo in March 2020. Would they always apply any software updates as routine on a service?

I've done a bit of googling on autos and steep inclines. There are a few websites where they do talk about trannies "going dry" on steep climbs.
To be sure I'll check my levels myself - the garage did it last (not volvo).

Volvo would yes as part of the "Service Promise software " which you get free at each volvo service .

[mr tickle]

Ok so this evening I have been doing the testing on my gearbox oil level, all done with oil at 50c, with engine running and on the level:

1) Add 1 litre of oil, remove small drain screw nothing.
2) Add another litre of oil, remove screw 100ml of oil!

So it looks like my suspicion was correct, it was low VERY low. 1.9 litres low

Q1 - Do any other parts i.e. oil pipes or water pipes run through the box at all so that it may have leaked that way as the underneath is bone dry no external leaks I can see?

3) The oil was VERY dirty, this is surprising as I did a 20 litre flush 5k miles ago. Since then the garage that replaced my EGR cooler had drained the box oil when checking for a water leak and I purchased the Genuine Volvo oil 4ltrs and gave it to the garage so they could top it back up. this was about 2k miles ago

Q2 How likely is it that the oil could have become very dirty in 2k miles after I had done a flush recently also vs the garage just put the old oil back in and kept my expensive new volvo oil?

I drained out the oil and put in the full 5 litre of oil for now so at least its had a partial replacement. I will order another 20 litre container and do another 4/5 drop and fills over the christmas.

I'm not a very happy bunny, feel like I may have had bad service from the garage and if driving around with dirty oil that was 1.9 litres lower than it should has not done any damage I may have got away with it.

On the plus side though, the clunk I've been getting when going From D to R or visa versa is not box related; the bottom engine mount is worn. I'll get one ordered and it looks very easy to do.

PS happy Christmas