Transmission going on 2006?

[openplanet]

2006 xc70 purchased three months ago with 223,000 miles. Two recent, transmission-related symptoms that I fear may portend serious problems, but would like to check here.

*brief, fast chattering (not grinding) prior to downshifting
*on highway, brief power loss followed by a mild "clunk"

Neither of these give me much confidence, and together...gulp. I knew I was taking a risk with the purchase ($4500). That chicken may now be coming home to roost.

Thoughts? Thanks!

[Astro14]

First - check the fluid level. Car must be on level ground, engine idling, fully warmed up. Use the dipstick.

Next - Change the fluid. Use the IPD kit, buy 14 quarts, and change it all using the cooler line flush method (Gibbons method) described in the IPD kit.

[openplanet]

Thanks very much.
So can I conclude that, given the symptoms I've described, there's a reasonable chance that a complete flush and refill could solve the problem?
I know you don't have a crystal ball...just wondering, based on your experience, what odds you'd give.
Again, thanks.

[Astro14]

Yeah - there's a chance. In this case, diagnosing over the internet and chat forums, it's hard to tell, but I would try the cheapest (fluid check) followed by the next cheapest (fluid flush) - that way, you'll know. It'll either get better - or it won't - in which case, you're looking at a rebuild.

[vtl]

Gibbons method really makes little sense. Transmission diverts only a small fraction of circulating fluid to a cooler line, especially when it is not boiling hot. The new fluid will get mixed in sump and in torque converter, so why bother with a mess? Just do 3 drain&fills, with a few miles driven in between.

I'd also recommend using Volvo ATF. It is cheap enough ($58 for 4 liters at FCP), our transmission likes it the best and it lasts the longest.

Your first symptom is called a shudder, it is an indication of worn out ATF, it has no friction modifier left. You can add 2-3 oz of Lubegard HFM, but really drain&fill with Volvo ATF.

Could you describe driving pattern/condition of your highway symptom with more details?

[Astro14]

Gibbons method really makes little sense. Transmission diverts only a small fraction of circulating fluid to a cooler line, especially when it is not boiling hot. The new fluid will get mixed in sump and in torque converter, so why bother with a mess? Just do 3 drain&fills, with a few miles driven in between.

I'd also recommend using Volvo ATF. It is cheap enough ($58 for 4 liters at FCP), our transmission likes it the best and it lasts the longest.

Your first symptom is called a shudder, it is an indication of worn out ATF, it has no friction modifier left. You can add 2-3 oz of Lubegard HFM, but really drain&fill with Volvo ATF.

Could you describe driving pattern/condition of your highway symptom with more details?

We disagree. The pump sends 100% of the fluid through the cooler, so, the fluid exchange works. It’s not instant because of mixing in the pan, but it does work and does exchange the fluid completely.

Drain and fill will mix the fluid - so, it is a mathematical certainty that you won’t get anywhere near the fluid exchange percentage using a series of drain and fill. Reason: capacity is 8quarts. Drain is 3.5 quarts. You exchange about 45% each time. Do it three times, and you’re nowhere near the completeness of a cooler line (Gibbons) flush. Do it five times, and you get close to the efficacy of a cooler line flush, but it will have taken more fluid.

Now, it may be that 45% new fluid will be enough to make a noticeable difference. It may not.

I’ve done both. Cooler line flush works better if the goal is a complete fluid exchange.

Fluid choice is up to you. The specification for this transmission is JWS-3309. Genuine Toyota (and Aisin is a Toyota company, so, Toyota makes the proper fluid) T-IV is often cheaper, and meets JWS-3309. Volvo fluid isn’t any better than Toyota T-IV, or Mobil 3309. I’ve used AMSOIL and Valvoline Import Multivehicle with success. Success being defined as a smooth shifting transmission that has nearly 300,000 original miles.

Seriously- in this case, choose whatever fluid meets JWS-3309 and is cheapest.

Drain and fill is easier than a cooler line exchange, but I would pick up the IPD kit, grab* a case of T-IV from your local Toyota place, and do a cooler line flush.


*If you ask nicely, they might give you a discount for T-IV bought over the counter, my dealer always does.

[vtl]

We disagree. The pump sends 100% of the fluid through the cooler, so, the fluid exchange works..

Nope.

[Astro14]

Nope.

Interesting picture - wish I could see all of it.

The pump has one output. The red line. So, 100% of the fluid leaves the pump through that line.

One input, the hashed suction line. From the pan.

I can't see all of the diagram, but the converter and lube line appear to end up in the pan. They're the only lines that return to the pan. So, it appears, that all of the fluid returning from all the valve body and other lines, end up in the lube and converter line. What I can't tell, is how much of that return is bypassed to the pan.

Any idea?

Because the Gibbons/cooler line flush is Toyota's recommended procedure for a fluid change on the Aisin transmissions I've owned. That's how the manufacturer suggests you change the fluid.

The manufacturer of the transmission suggests a cooler line exchange, not multiple drain and fill.

I am out of town and don't have access to VIDA - what does Volvo suggest for fluid change?

[vtl]

Interesting picture - wish I could see all of it.

The pump has one output. The red line. So, 100% of the fluid leaves the pump through that line.

One input, the hashed suction line. From the pan.

I can't see all of the diagram, but the converter and lube line appear to end up in the pan. They're the only lines that return to the pan. So, it appears, that all of the fluid returning from all the valve body and other lines, end up in the lube and converter line. What I can't tell, is how much of that return is bypassed to the pan.

Any idea?

Very little. The cooler line can't hold much pressure, valve body has to mediate it, especially in colder temps.

Transmission's oil pump is comparable to the engine's one. No way it can squeeze it all through that tiny cooler line.

Because the Gibbons/cooler line flush is Toyota's recommended procedure for a fluid change on the Aisin transmissions I've owned. That's how the manufacturer suggests you change the fluid.

The manufacturer of the transmission suggests a cooler line exchange, not multiple drain and fill.

I am out of town and don't have access to VIDA - what does Volvo suggest for fluid change?

It suggests doing fluid change through cooler line, because a tech can disconnect it easily and attach both ends to the machine, which will exchange fluids automatically.

[Astro14]

Back to the OP’s question and a recommendation, now that I’ve been educated on this…

OP, did you at least check the fluid level? Have you tried some form of fluid change?