Piston Slap: Crystal Ballin’ With Yo Tranny! (Part II)

Aaron writing :

Hi Sajeev,

Big fan of TTAC items and pistons. My problem is that I noticed that my car (Honda Civic 2007) was shaking, throttled slightly, and had low RPMs, especially going up a slight incline. This usually happens at 30 km/h or 40 km/h. I took it to the Honda dealer (4 months ago) and he told me the torque converter (tc) needed to be replaced (300 for tc plus 900 for labor and all).

My university was a bit busy and I took some time to think about it. The problem might be a little worse now so I recently went back to the dealer for more cost details and now they say the price of the tc has gone up to 800 plus another 800 for labor. The guy suggested maybe just change the transmission fluid (because it’s getting dark) and drive the car until it breaks down and get a new transmission for $3000 because the transmission will probably die soon anyway.

I do not know what to do now. I’m considering going to a transmission shop and see if they can change the tc, but I’m scared to go to a random mechanic. I know a little mechanic that I go to for little things, but I don’t know if his shop can change the tc (is it that complicated?). I’ve also searched online and found other people saying that if the torque converter fails, the transmission will probably fade soon. Some other people have said that if the torque converter fails, it could cut off the rest of the drivetrain that might have otherwise worked just fine. Then I found another group of people saying that I should drive the car without changing the transmission fluid because even changing the fluid could cause the transmission to fail sooner.

I just want to know which of them are actually true and what my next course of action should be. If the torque converter can be changed for a reasonable price and my transmission still works, I’d like to do it. Or maybe I should see if I can rebuild or replace the entire transmission.

Thank you,
Aaron

PS I don’t know if this matters, but the car once severely overheated (about 3 years ago) and about half the engine had to be replaced under warranty. The engine has run flawlessly ever since and the only other issue is that I recently (2 months ago) had to replace my starter and battery. The battery connectors look pretty bad too, so I’ll be replacing them soon. Hmmm, maybe I should sell my car.

Sajeev answers:

Oh great, another mysterious problem with the box/crystal ball transaxle – someday the B&B will put me on the ropes for that blind guess.

That said, on a more serious note, how many miles does the Civic have?

Aaron answer :

Hi Sajeev,

Thanks for the quick reply. It has 156,000 km (96,000 miles). True, the car drove quite hard. I just did a quick stall speed test (squeeze the brake and step on the gas) and the revs are up to 2500rpm in forward and reverse. It seems quite normal. I drove trying to recreate the problem (light acceleration and flat roads or slight inclines).

Happens in:

• 15 or 20 km/h (9 or 12 mph)
• 30km/h (18mph)
• 40km/h (25mph)
• And at 55 km/h (34.18 mph), the thrill is less at that speed

There is also a sound when this happens, it sounds like metal spinning against metal in a liquid. However, this sound can only be heard if the emotion is not too violent. If it is violent, it seems that the car wants to stop. I checked the transmission fluid and it looks pretty brown and has a slight burning smell. If the car accelerates faster (at least above 2000 rpm), it seems that there is no problem. No problem at idle either.
Thank you,
Aaron

Sajeev concludes:

Excellent review! At this age (less than 100,000 miles) chances are new and the right fluid will fix it: flush the old fluid out of the converter and also drop the pan to change the filter. Which might be asking a lot for many stores, but I would like to see all the old ATFs removed from the system. Will this solve the problem? Will complete removal of the varnished ATF cause even more trouble than a shiver?

Perhaps in both respects. Or maybe one and not the other. Do you see how much fun this is for me?

My best guess: do what the dealer said, change the fluid. If that fails, get a rebuilt transaxle from a knowledgeable Honda shop. Because opening up a transaxle for anything and not doing a rebuild is probably a waste of time, work, and money.

It’s usually best to extend this time with anything…including a fluid change. Although the fluid change actually shortens the lifespan of the tranny. Very funny!

[Image: Shutterstock user Scharfsinn]

Send your questions to [email protected]com. Don’t skimp on the details and ask for a quick fix if you’re in a hurry… but be realistic and use your make/model specific forums instead of TTAC for more timely advice.