S70 Transmission Problem

[dennisphillips]

Hello,
I have a '98 Volvo S70 with 195,000 miles on it. Recently, the shift-up arrow started flashing, which I understand indicates an issue with the automatic gearbox. It was on for a couple of days, then turned off briefly before coming back on again. I was out of state when this occurred and drove for six hours with the light flashing, but everything seemed fine—no slipping and RPMs stayed around 2800 at 70 mph.

Once I got home, the light went off for a short time before reappearing the next day.

I tried moving the shifter back and forth to clear the contacts on the PNP switch, but that didn’t help.

I checked my transmission fluid, and it's quite dark. I haven’t changed it in a while and drive a lot. Recently, I had a leak from an axle seal, which I replaced, but the lubetech guys put in cheap dex/merc instead of Mercon VI. I plan to do a drain and fill tonight to see if that fixes the problem.

I’d love to hear if anyone else has any suggestions!

[abscate]

Jimmy57 (Volvo techs) recommends DexVI for these transmissions. I use the Valvoline maxlife in all my Volvo ATs except the xc90 where I use Volvo stuff

[yanga001]

Drain and fill fluid, no power flush. What gear does the flare occur in and is reverse affected? Usually reverse is our canary for bad transmissions, if it’s dead or funny, the trans may mechanically have issues.

You should get it scanned to know the actual code. If there are no shift flares then that is a good sign for you.

I once purchased a condemned s70 for parts due to a bad transmission that stuck it in limp home mode. My very rare and obscure issue was rectified by a used TCM which allowed the car to drive normally. Never tore down the old TCM, and I suspected it wasn’t mechanical as my reverse gear was solid.

See if you can get the car scanned cheaply or buy a Volvo bidirectional scanner for like 200-250cad. Volfcr will also work if you can setup virtual box with a vagcom kkl cable. If you are in central Ontario then shoot me a message.

[scot850]

I had a V70 with a orange arrow code. Issue was not the trans itself, but as has been mentioned the TCM. It was not the TCM itself but the contact pins between it and the harness had oxidized/corroded pins. The dealer cleaned the connections and installed/removed it a few times and it cleared the issue.

Neil.

[rolsen11]

Is it common that transmission shift issues are caused by the TCM or is it failing solenoids on the valve body? Or maybe an even mix of both? I ask because my car has an occasional 2-3 flare that is heavily exasperated by putting the car in park and back into drive without shutting the car off or by idling the car in drive for too long, as well as a hard shift when going into drive when I do either of those two things.

[abscate]

Karla kat, the low mile s70 awd rescue, had a tcm code for lockup solenoid failure which was cured with one drain amd fill and a month of running.

[yanga001]

Is it common that transmission shift issues are caused by the TCM or is it failing solenoids on the valve body? Or maybe an even mix of both? I ask because my car has an occasional 2-3 flare that is heavily exasperated by putting the car in park and back into drive without shutting the car off or by idling the car in drive for too long, as well as a hard shift when going into drive when I do either of those two things.

So this gets a bit muddy. I once had shift flares due to Torque on the axles due to bad motor mounts. In my case, it happened sporadically on side roads, highways, and almost in any gear.

I have also driven an Infiniti with an actually bad transmission. It’s flares got better after drain and fills but were still present in stop to first gear.

That gear usually takes the heaviest beating as it’s in stop and go traffic, and needs to overcome the most inertia to get the car moving normally.


My rule of thumb is if the issue only appears in an exact certain situation, (in certain gears, is physically observable, etc) and has worn fluids to match, then it could be more mechanical than electrical.


However, these are aisin transmissions which are extremely strong. The car will likely still keep going for a long while.

[V50M66]

See if you can get the car scanned cheaply or buy a Volvo bidirectional scanner for like 200-250cad. Volfcr will also work if you can setup virtual box with a vagcom kkl cable. If you are in central Ontario then shoot me a message.

The 850 OBDII app and a cheap ELM327 dongle is an Android port of the genuine Volvo tool, and even does more than the factory tool (like getting out of ECC infinite relearn cycles). It’s all you need for 96-98 P80, no $200 crap required.

OP, get the app, a dongle (the $14 Panlong off Amazon is great), and pull codes. Without scanning the thing, you’re just taking stabs in the dark.

[yanga001]

See if you can get the car scanned cheaply or buy a Volvo bidirectional scanner for like 200-250cad. Volfcr will also work if you can setup virtual box with a vagcom kkl cable. If you are in central Ontario then shoot me a message.

The 850 OBDII app and a cheap ELM327 dongle is an Android port of the genuine Volvo tool, and even does more than the factory tool (like getting out of ECC infinite relearn cycles). It’s all you need for 96-98 P80, no $200 crap required.

OP, get the app, a dongle (the $14 Panlong off Amazon is great), and pull codes. Without scanning the thing, you’re just taking stabs in the dark.

The 327 is not a real clone by any means, usually a more entry level solution. That being said, I would get the vag com kkl tool and install volfcr on virtual box as those are a similar price in china. Note, as you get newer in the years, you will see that most brands decided to bury a lot of diagnostic under proprietary can bus codes and access. Hence why we have many bidirectional scanners of odd formats.


I got an old 327 kicking around but it would take a while for me to find the time to compare it on my 98 s70 up north to a vag cable and my 200$ scanner .