Is there a way to test an automatic transmission for wear?

[Kurtatron]

I’ve owned manual transmissions most my entire life. After a leg injury, I can’t do that anymore.

Being naive about automatics, I wanted to learn about test driving them.

Are there ways to gauge an automatic’s health during a test run? Say I’m buying a used car, what things can I pay attention to? Or do automatics generally just fail suddenly without much warning? What can I do?

 

[The_Jeff]

With dodges you could look at the "adaptives" or at least you used to be able to in 1990's models. That shows how much the computer is compensating for wear.

It's worth scanning ANY used car you look at to see if the codes were just cleared. It's a midsize red flag that nearly everyone ignores, so you're not likely to whittle down the seller based on the I/Ms being incomplete. But it might help you dodge a turkey.

 

[SShooterZ]

I would look for transmission fluid changes. Not necessarily a flush, but was there a drain and fill every 30-50K miles depending on the car and the usage.

 

[slacktide_bitog]

If it shifts smoothly and doesn't have any transmission-related codes, the transmission is good. Just change the ATF regularly to keep it that way

If it isn't too new to have a transmission dipstick, check the fluid while the car is running (and warmed up). NOTE: In a Honda, you check the fluid with the car off, but everything else you check the ATF while the car is running. If the fluid smells burnt, the transmission is on its way out.

How old a car are you looking at?

 

[zzyzzx]

Is there a way to test an automatic transmission for wear?​

Not really, no. I mean as long as it works, you can only look at the mileage and hope for the best.

 

[Chris142]

In my past I had transmissions fail. Usually they work till they don't one day.

 

[Marcozi]

Send a pm to clinebarger. He's the transmission expert.

 

[Lubener]

Initial engagement quality without delay. Quality of the shifts without run away between shifts. Also, the appearance of the fluid. Anything else is more involved such as the amount of debris in the pan, magnet and filter.

 

[brages]

IMO full-throttle acceleration 0-60, look for slipping (slow shifts, flare followed by slamming in to gear, etc)

 

[nascarnation]

Depends on what the failure modes are.
You can pull the pan (if it has one and see what's in there). Not many used car transmissionactions are gonna have that happen. Or look at line pressure in various ranges.
Probably your best bet is be informed on what the particular problems are with the vehicle you're looking at.
Chrysler minivans with failing torque converter thrust bearings, GM transmissionverse with cracking clutch wave plates, Fords with a bushing displacing in a clutch drum cutting off pressure feed holes, Ford/GM 10 speeds with valve body wear issues, etc. There's a lot of parts to fail in a 8/9/10 speed auto transmission these days.

 

[D60]

If it has a lockup converter, make sure it actually locks at highway speed. You can tell by watching the tach. If it's a base model w no tach, good luck -- you could bring a scan tool and watch that

Beyond that, there's not a lot of "testing" for the common man. I'd get after it a few times and see how harsh or slushy shifts are under load, esp UPshifting.

 

[Exhaustgases]

What kind of Transmission? Normal step type or CVT?
Fast an simple test is the stall speed. Can also let you know if the applied clutches or band is slipping, or the pressure is not good.
Test drive and feeling for slippage, and how the shifts feel, shift points etc.

 

[PontiacHO]

I’ve diagnosed more transmission issues by soft driving feeling the shifts and engagement especially at operating temperatures. Less line pressure can detect slipping. Listen for unusual noises. It’s ideal if the test drive includes a cold engine-transmission driving to start off and to include until full operating temperature test with a few full throttle take offs and rolling downshifts. Then smell the fluid for burnt smell. If the fluid has been changed sometimes it’s hard to detect.

 

[Kurtatron]

In my past I had transmissions fail. Usually they work till they don't one day.

That makes me nervous. That’s why I tried to keep to manuals for so long.

So even if a transmission is shifting crisply, smoothly, and quickly at WOT, that doesn’t mean that it’s not moments away from failure?

 

[JunkdrawerDog]

According to WLS radio dj Larry Lujack, check the presets on the radio. If they're all rock and roll stations, odds are the transmission is shot.

 

[goblin]

I’ve owned manual transmissions most my entire life. After a leg injury, I can’t do that anymore.

Being naive about automatics, I wanted to learn about test driving them.

Are there ways to gauge an automatic’s health during a test run? Say I’m buying a used car, what things can I pay attention to? Or do automatics generally just fail suddenly without much warning? What can I do?

This is one of the topics where the artificial brains widely advertised this last year or two can be surprisingly helpful. Ask for a testing strategy providing the exact model, mileage and conditions of the test.

I was almost convinced I shot myself in the foot after my last ATF fluid change till I asked the smart bag of silicon chips and it pointed out while my transmission was behaving weird and what I needed to do to make it re-learn.

 

[Chris142]

That makes me nervous. That’s why I tried to keep to manuals for so long.

So even if a transmission is shifting crisply, smoothly, and quickly at WOT, that doesn’t mean that it’s not moments away from failure?

I took prefer a manual. But autos that are not cvt are usually not THAT bad . Our 07 Toyota had 227k on its automatic and it still shift fine.

 

[ClutchDisc]

I prefer a manual any day over an automatic. But for certain circumstances I have more automatics than I do manuals. Basically I see how they drive, and check the fluid condition. I have yet to buy an automatic without a dipstick on the transmission so that would certainly complicate the checking of the ATF before buying. I have only ever had one automatic transmission failure.

 

[Astro14]

Automatics last longer with clean fluid - look for a car with a history of fluid changes. Even one change on a 100,000 mile car speaks to careful maintenance, and likely, a long life for that transmission.

Case in point - my wife’s 2002 Volvo V70XC. Bought used at 93,000 miles. I changed the fluid for the first time not long after purchase. It has had regular changes since. It is at 308,000 miles on the original transmission. There is more detail to the story than just the fluid changes, I added a cooler and filter, but the point is - they can last a very long time.

 

[Sequoiasoon]

Daughter's '08 CRV with 250k, knock on wood, no issues. It has had many fluid changes. Son's '10 Forte with 198K same thing. Old Sequoia was 196K no issues, multiple fluid changes.

'19 Pilot, 78k with I think 10 drain and fills, added cooler = new torque converter.