Automatic-Transmission Replacement, Fuel-System Flush


New member
I own a 2003 Corolla with automatic transmission and about 77K miles. I bought it used from a shady dealership about 10K miles ago, having gotten into a car accident and needing to buy a car quickly. I know very little about cars.

I recently got an oil change at a quick-lube place, and as always, they were trying to get me to buy other services, notably a transmission-fluid change and a fuel system service or flush.

I went home and went to take a look at the ATF myself, only to find that the dipstick said the ATF should not have to be replaced with normal driving. After 15 minutes of driving and a double-dip with the dipstick, the fluid appeared brown. So do I really need to have the ATF changed?

Meanwhile, the guy a the lube place showed me some black sludge he found in the engine and told me it shows I need my fuel system flushed. How do I know if he's telling the truth?




New member
brown or black ATF is bad. it should be pinkish colour, definitely get it flushed. I flush mine ever 25,000 miles. pour in type of fluid instructed in the car's manual. the longest interval i changed my fluid was about 35,000 miles after 3 years and the fluid was still pink with a brownish tint. im guessing the ATF in your car was never changed or its over 50,000 miles old. if everyone in america changed their oil and ATF when required so many expensive car maintenances would go away.


RF Overlord

New member
If the transaxle fluid is brown, it needs changing. That "lifetime fluid" stuff is bunk. What it really means is the lifetime of the warranty. What ever_green said above is exactly correct.

As far as fuel system flushes from a Qwik-Lube, forget it. It's a scam. If the car is running well, just put a bottle of Chevron Techron or Gumout Regane in the tank a couple of times a year and it will do all the cleaning you need.



I know Karate, Kung Fu, and 47 other dangerous wor
The transaxles in the 9th gen Corollas use Toyota Type T-IV ATF and not interchangeable with some fluids out there. Whatever ATF was used, make sure it says that it meets the specs for Toyota Type T-IV.

Also, many owners find that the fluid can take on a pretty dark color, even if less stressful driving conditions (ie. highway cruising). Doing a drain and refill every 30K-60K miles would be very beneficial in those cases. Granted, will not get all the old fluid out, but is less of a "shock" the transaxle and the introduction of fresh fluid has been shown to greatly boost the additive properties of the existing oil already in the transaxle (refreshing of the additive pack).

I agree with the others - fuel system is pretty hardy on this car. Unless you've been filling up from unknown gasoline sources, the additives in current gasoline blends is more than enough to keep the engine clean. I'd be more interested in where the tech supposedly "wiped" the sludge from the fuel system? That has all the earmarks of a scam job there.


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