A neighbor told me my car's transmission fluid was actually fine... after I already spent $800 on a flush

I was about to junk my 2004 Camry because the shifts felt rough, but my neighbor who works at a shop said sometimes a hard flush on an old transmission can make it worse by dislodging gunk. Has anyone else had a shop push a fluid change on a high-mileage car that should have just been left alone?

3 comments

3 Comments

rose_hart10d ago

The neighbor probably isn't wrong and it might not be that serious. I've seen plenty of high mileage Toyotas run another 50k miles on the original fluid with no issues. A flush on a 20 year old car with 200k miles is basically asking for trouble because that gunk could be the only thing holding the seals together. $800 is a lot for a flush too, usually runs half that. Your call but I'd just drive it easy and see if it smooths out over time.

richard_dixon10d ago

Flip it around and look at it from the other side. That old fluid is full of clutch material and friction modifiers that are broken down and useless. Leaving it in means you're basically driving around with dirty oil, grinding those already worn transmission parts together with nothing to help. A flush with good, clean fluid will give those seals a chance to swell back up properly, not just rely on sludge to fill the gaps. And 800 bucks for a flush is steep, sure, but it's nothing compared to a transmission rebuild that costs 3 grand or more. I'd rather pay that now and know exactly what I've got instead of rolling the dice on 50k more miles of unknown damage. You might get lucky, but you're just as likely to end up stranded with a dead truck.

bennett.noah5d ago

That 50k more miles is a pretty big gamble though, especially if the fluid is already dark and burnt. How do you actually tell the difference between "gunk holding it together" and just really worn out fluid that's about to cause a hard failure? I mean, a smooth-running transmission with fresh fluid is one thing, but a clunky one with old fluid feels like a ticking time bomb to me. Is there a real way to check the condition of those seals without just hoping the sludge is working?