Clod weather shifting problem

[lemanski63]

Hello all - like many parts of North America, Northern Alberta is in the middle of a cold snap which has ben going on for two weeks now. My 2002 XC70 has been OK, up until Friday. Leaving work, the car seemed to slip in 1st gear for about 1 city block. Even at 3000 rpm, the car was crawling. After a few minutes, all was well. I was on a really icy section in the strip mall where I work, so I put it down to that, but facing a family trip to Jasper Alberta to do some skiing (350 km away), I put a call in to my indy mechanic friend who replaced my exploded bevel gear in the spring. He reminded me that it was freaking cold, and that it was possible that the tranny software prevented full-speed operation in extreme cold temps. I was advised to check fluid before I left, but the manual does not refer to a transmission dipstick. The trip to Jasper was uneventful.

Saturday morning, we woke up to -38C Needless to say no skiing, but the same problem when I went out later that morning - no problem with reverse, but the car would crawl at about 3000 rpm for about two blocks - after a few minutes of that, everything was allright. Since I had a lot of time on my hands, I checked this forum, and found the dipstick location - after 1 hour of drive time, the trans fluid level was just up to full cold, and the fluid looked pretty brown (the previous owner had told me that he changed it sometime between 50K miles and when I bought it at 85K miles). Also, my new water pump seemed to be leaking a little bit. Sunday, it was just as cold and the same problem - 1st gear slippage for about two blocks, then no problems as the fluids warmed up.

I got a hold of another mechanic buddy of mine in Jasper who has a lot of Euro experience, fortunately his shop and hoist were open, and we had a look to see if I could make it home. Looked like the water pump issue was just from the vent hole, and since no one in town had 3309, he topped off with less than .5 liter of Dexron/Mercon - our logic being the wrong lubricant is likely better than none. We made it home with no transmission issues, no shifting problems (other than some weird climate control problems, but that's another subject).

Three questions -

1 - has anyone else experienced this type of problem - first gear slippage at extremely cold temperatures, and what might be the solution?
2 - I was taking a calculated risk with mixing in the Dexron/Mercon - a flush is coming soon - but could that cause future damage?
3 - asked tounge in cheek - where is the global warming part of climate change, and could we get some right now, especially in Northern Alberta? -38C is bloody cold!

I'm going to work tomorrow and will report on the condition - wondering if the top up has made any difference.

[MT71]

Hi lemanski63,

Canadian winter can be pretty tough on cars. I think that our tranny have different mode according to the temperature, driving style, etc. Maybe the tranny software is not ajusting properly.

The fluid level seems to also have impact on the performances of the transmission. If you mixed two type of a/t fluid, I would strongly suggest you to drain your transmission fluid and start with fresh one. Look for the Gibbons method in this forum. The general opinion is to avoid flushing.

We have many expert here, I'm sure they will chime in.


Also, welcome to the forum....Marc

[duncan]

One thing worth mentioning is that the car purposely holds the gears longer when it is cold. I am not sure if this is what you describe, but when starting off with cold fluids it will hold first gear much longer than normal. So for me it will hold first gear until 3k, which definitely makes it feel like it's crawling. This is to warm up the catalytic converter. Once you are up to normal operating temperature, it will shift as you'd expect.

[BLUEH20]

The wrong transmission fluid is worst than a slightly low fluid level. Change it out--then come back and read the rest of my tripe.

Go! Go! We'll be here when you get back.

Got it do--go on you and shame on you buddy.

You transmission will shift slowly, slopply and some times not at all when it is very cold to extremely cold. The older and more worn out the fluid is; the longer it takes for normal operation. The transmission fluid must warm to it's operating temp for proper operation--the norm is approx 178 degrees or very close to that. It gets there in a matter of minutes.

Is your vehicle equipped with the "W" buton for Wet Weather? If so use it during these icy days--it locks out first gear and has you run from Second on. This will causse the vehicle to feel sluggish out of the hole but it does help quite a bit with traction and wheel control.

[JRL]

NEVER use the "W" button

[Aviator]

You're right Duncan, however I don't think that's the problem, simply because he hasn't complained of the problem at warmer subzero temps or even the low pos temps. The transmission will always start in first gear unless there is some way of making it NOT start in first, i.e the "W" button, or using Geartronic and bumping into second.

Dave.

[lemanski63]

Thanks folks! I know I committed evil by mixing the fluid - going in for a flush the Monday right after Christmas. I only need to drive to and from work for the next few days, no epic trips planned over the holidays - less than 100 miles likely (please forgive the mixing of metric, I'm in Canada but my XC is from the US).

The update is, although it was not quite as cold this morning, shifting was fine to and from work.

Thanks for all the input and suggestions, I'm glad to hear that so far it doesn't look like my tranny will go to the great big smelter just yet....

[BLUEH20]

JRL

Expand on your pronouncment.

[duncan]

BLUEH20,

Then general thought is that "W" mode is excessively hard on your car, as you are starting off in a high gear. This of course is tough on the transmission especially, which our vehicles are not exactly known for. Someone else can elaborate on this, but I have heard many warnings to never use "W", unless you absolutely have to (not likely).

[billr99]

BLUEH20,

Then general thought is that "W" mode is excessively hard on your car, as you are starting off in a high gear. This of course is tough on the transmission especially, which our vehicles are not exactly known for. Someone else can elaborate on this, but I have heard many warnings to never use "W", unless you absolutely have to (not likely).

I've only used the "W" button a couple of times and have never had it activated from a dead stop. The times I've used it (not in the XC by the way, but an older V70) I was in a situation where the tranny was continuously shifting between second and third because of the slow speed and a bit of up and down to the terrain. Further, because of the lack of traction every shift was throwing the car around. The only thing "W" really did in this case was to keep the tranny in third gear and it allowed me to drive the car more with the throttle (the preferred method being the old manual shift guy that I am). I suspect in a similar situation in the XC, I'd just go to geartronic mode and hold the gear that way. I never used the "W" in my 5-speed R either so the bottom line here is that I see little benefit in the mode. Seems more a gimmick for those who are not really comfortable in the cut-and-thrust of real winter driving.

Cheers,

Bill