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Clutch fluid replacement?

I wanted to know if anyone has ever replaced the clutch fluid on a perfectly well running car. I’ve checked the owner’s manual and there’s no mention of it.



On the other hand, they say that the brake fluid should be replaced because it tends to absorbs moisture from the air. Moisture will eventually condensate and accumulate at the bottom of the brake lines, rusting out the metal parts in contact.



Well, clutches use brake fluid. So water will probably also condensate at the bottom. Yet there is no mention of replacing clutch fluid??





Your opinion would be greatly appreciated.

I do not know about “clutch fluid,” but if you are referring to gear oil, that should be replaced every 30-60k miles. I don’t think any other service is required for a manual transmission until the clutch is replaced.

I was referring specifically to the clutch, which uses brake fluid. I have never heard of clutch fluid replacement either, until a friend of mine mentioned it.

The logic being that brake fluid will absorb moisture. So if it is replaced in the brake lines, why not replace the clutch fluid? Same stuff.

But the owner’s manual does not mention it.

A quick Google search has come up with a couple of sites calling for replacing clutch fluid “periodically”…

Does your manual tell you exactly what kind of fluid to use? If you plan to keep the vehicle for a long time, it makes sense to change it the same as brake fluid, probably every 3 years regardless of mileage.

I’ve replaced the brake fluid and “clutch fluid” on my 92 Accord (264000 miles) every two years since I bought it new. Only thing is, it’s a real bear to bleed the clutch hydraulics if you drain all the old fluid out. Have to pump the system about 1 million times to get the new fluid into the system. I recommend not draining all the old fluid out before adding new fluid. That way the system is never without fluid.

Same as the brakes: DOT 3 or 4.

“I’ve replaced the brake fluid and “clutch fluid” on my 92 Accord (264000 miles) every two years since I bought it new.”

That’s it.

If I may ask: what made you do it? It is not written anywhere in the owner’s manual.

I replace my clutch fluid when I replace my brake fluid, only replacing the clutch fluid is a little easier. I drain out as much as I can with a siphon pump and refill it.

He probably does it for the same reason I do it, even though it isn’t in the owner’s manual; it is cheap and easy to do.

Normal maintenance includes opening all bleeders and letting them drip while under the vehicle and topping off with fresh fluid when the oil is added. High mileage fleet vehicles that get monthly service accumulate hundreds of thousands of miles with no hydraulic failure.

I approve the easy method because the system is so small that it will make a difference. Brake fluid will absorb moisture and the water will not accumulate at the bottom.

If it makes you feel/rest better go for it.

However I know in my car ownership and family’s with vehicles running well into 200k-300k range they never performed as maintenance.

One of the reasons to change the brake fluid is that the absorbed moisture lowers the boiling point of the fluid. Since disk brake calipers can get quite hot, boiling the fluid can be physically dangerous i.e. loss of braking action. The clutch fluid does not experience the same heat build up. Also, if the clutch hydraulic fluid were to boil you would lose the ability to disengage the clutch but it isn’t as physically catastrophic since you can pop the tranny into neutral or shut off the engine to eliminate power.

However, I agree that the brake and clutch hydraulic fluid should be flushed on a regular basis to also reduce corrosion in the systems.