2006 XC70 Transmission Grabbing/Slipping

[kderrick]

My xc70 has just under 100K miles on it, I bought it at 96K. My commute to work crosses a mountain range (1800' climb and descent) whic I do, of course, twice a day.

I first noticed my problem during the ascent on a day when the traffic was in stop-and-go mode due to an accident. I've since seen it in other stop-and-go traffic on the flat (San Jose spends a lot of time doing stop-and-go on the freeways).

Symptoms occur during automatic shifts - I think between 1st and second, but it may happen between 2nd and 3rd as well.

I've seen:

• RPM flare during down shift followed by sharp grab (as if it slips into neutral then engages at too high RPM) on both up and down shifts
• Jarring up shifts between 1st and 2nd - no obvious RPM flare.
• Apparent brief 'drop out' of gear and grab back when crawling.

This only seems to happen in stop-and-go traffic (i.e. low speed, lots of low-range shifts), usually after half an hour or so of driving. I am not making any large changes in the accelerator (i.e. I pull off slowly when the "go" part of stop-and-go happens).

I consistently get a very hard grab when shifting from reverse into Drive (such as when reversing out of the driveway and changing gear to pull off). I can avoid this by pausing in Neutral for a few second between reverse and drive.

Traffic is always horrendous and dangerous when these things happen so I haven't been able to focus on the instruments to characterize it thoroughly.

I took it into my specialist after the first occurrence (trustworthy and worked on my cars for 17 years, and there's no Volvo dealer in my city).

No codes found. But they did a full CAN-bus update to ensure I had all the latest firmware in the ECUs. Nothing for the transmission, but the ETM got updated. We also reset the adaptation. I've done easily 500 miles since then, so it's had time to adjust.

Oh, and this morning I got the "Reduced Engine Performance" message when I first started her. A restart a few minutes later did not re-trigger it, and I've not seen it since.

Before I take it back again, I'd really like some good hypotheses to explore.

Thanks

[oragex]

Is it a 5 or 6 speeds? The 5 speeds was ok, but the 6 speed Geartronic (it has the 'manual' shifting mode) is known for failure.

In stop and go traffic, or mountain driving, the fluid heats up even more, causing it to loose it's properties. I would replace it asap with the proper spec. Also make sure the radiator fan works properly.

[precopster]

Geartonic was optional on all 5 speed variants so this isn't an indication of which transmission is fitted. My wife's 2002 XC70 has Geartonic as does my 2001 XC70 and 2006 XC90 all fitted with 5 speeds.

The six speed didn't make it to the pre-2008 P2s in any case and wasn't even fitted to 2009 S60s which share the same platform.

The fluid simply has to go as a first measure. All that mountainous driving is destroying the fluid with heat. 4 or 5 successive drain and fills will replace 90-95% of the fluid by dropping 3.5 litres from the drain plug. If your mechanic has a new transmission seal clip from Volvo you can perform the Gibbons method which gets rid of more fluid in one session and may only need to be done 3 times for a complete transference.

There are a couple of synthetic brands of JWS-3309 compliant fluid out there. One may be Amsol. Synthetic fluid will best handle the heat generated.

A transmission shop may be best suited for this work. Most of them have now realised that high pressure flush machines can dislodge dirt from the pan area so if you're going this route ask them what pressure the machine runs at. If at the same pressure as the transmission's own pump then this is fine and can be done in one session.

To find out why you have reduced performance you'll need a scan of the car and it will be an engine related problem; not transmission.

[kderrick]

Thanks all. Pretty sure it's a 5 speed, those it does have the geartronic feature. Will have to track down a transmission specialist, it'll probably be over in the valley as we don;t have a lot of choice here on the coast.

So, if a flush and replace of the transmission fluid doesn't fix it ... what else is it likely to be?

[abscate]

I'm guessing you are Santa Cruz?

Song has a great indie who helped him sort out a tough problem on his Volvo..I'll try to find a link. I might have out the reference in the Mechanic forum?

Here you go...t he moderators here are just great, aren't they??

https://www.matthewsvolvosite.com/forums ... 27&t=75746

[vtl]

One may be Amsol. Synthetic fluid will best handle the heat generated.

I've had pretty bad experience with Amsoil (thicker one) in transmissions, which started to show wear signs.

In CA he can easily get Aisin 0T4, Idemitsu Type-TLS or Mobil 3309.

As for the heat - that's the job for additional oil cooler.

[kderrick]

I'm guessing you are Santa Cruz?

Song has a great indie who helped him sort out a tough problem on his Volvo..I'll try to find a link. I might have out the reference in the Mechanic forum?

Here you go...t he moderators here are just great, aren't they??

https://www.matthewsvolvosite.com/forums ... 27&t=75746

Yep, Santa Cruz so you know the traffic I deal with.

The phrase "shift flare" got me a much more focused set of google results and it seems I have the right (or wrong!) transmission (AW55-5X) to need the B40 cover replacement as well as the transmission flush.

ipd seems to have the parts I need:

https://www.ipdusa.com/products/5538/10 ... aw55-50-51
https://www.ipdusa.com/products/4808/10 ... h-hose-kit
https://www.ipdusa.com/products/10891/1 ... uid-funnel
https://www.ipdusa.com/products/10543/1 ... nsmissions

Is this something a relatively non-mechanical car owner can manage on their own? The B40 cover looks like it will either be straightforward or a complete nightmare

I've been going to Specialized since 2000 - but they didn't pick up on this even after my description. To be fair, Larry took it out and spent an hour trying to reproduce the problem. So maybe I'll give AE a shot at it, if it's not something I can do in an afternoon: though they don't mention transmissions in their list of services (which seems to list just about everything else)

[kderrick]

I've had pretty bad experience with Amsoil (thicker one) in transmissions, which started to show wear signs.

In CA he can easily get Aisin 0T4, Idemitsu Type-TLS or Mobil 3309.

As for the heat - that's the job for additional oil cooler.

ipd grades Aisin as a "Better" quality level - is there a "best" quality ATF?

Also, you mention an "additional oil cooler". Is that an additive? Or do you mean an extra physical component? If the latter, is that some optional part on an XC70?

[abscate]

I don't think the flare issue was still a problem in 2006, I would hear precopster out on this before you sink effort into these parts

[precopster]

The B4 servo cover problem.affected transmissions with serial numbers beginning with 1A to 1L which were mostly manufactured between 2000 and late 2001. If the flare is between 2nd and 3rd gears on upshift the B4 cover may have deformed enough to cause a problem.

Just rereading your symptoms and decided that they are a pretty good match for valve body failure; particularly the solenoids in the valve body.

There are kits to reclearance them for under $150. If this is too risky jist replace the valve body with a rebuilt by Reamman or VBX.
I would without a doubt still be replacing the fuid in total and looking into an external cooler based on your driving.