So, I did my first brake job on my car a couple weeks ago (detail here: https://themustangsource.com/forums/...elcome-536979/) and I also bled the clutch/brake fluid at the same time, and replaced it with Castrol DOT 4 fluid instead of the stock DOT 3. Since I did that, the clutch/shifting action feels different: it's not as forgiving - shifting/rev-matching needs to be almost perfect where it definitely didn't before. I swear this isn't a placebo effect but I don't know how the clutch fluid could/would affect that.

Thoughts?

 

can I ask you, have noticed that your clutch may be slipping, resulting in a clutch burning type smell when you rev/drive hard?

 

I haven't, and I drove it pretty hard for about 80 miles on my favorite backroads last weekend. Also have had to start from a stop on some pretty steep hills and not noticed any issues.

Thinking I did the fluid flush wrong or just that the clutch may be wearing out?

 

well, From a few pointers, my buddy (mechanic) told me that the good ol' pump brake action is recommended with two guys.


One guy pumps, and the other constantly keeps topping up the reservoir, to avoid getting air in the system.

He said that if it were to be a one man job, open the bleeders and let it drip on its own, which is a really slow going process and keep an eye on the reservoir and keep topping it up accordingly until enough fluid has passed through.


So, I'm not really sure if your issue has anything to do with air being in the system. dot 4 definitely wouldn't have any adverse affect either. dot3/dot4 can be blended.


I'm just trying to think of different possibilities and was thinking out loud with my original post asking.


Its possible your clutch could be wearing out, all depends on how those 70k miles were put on but again, I doubt that your issues you're seeing have anything to do with how worn the clutch is.

 

No that's awesome, thanks for thinking through all the possibilities! Since the brakes feel + work correct, I have to think there's no air in the system, unless it's possible to have air in the clutch system but not the brake. Wouldn't think that would be possible with a shared reservoir.

 

Try pumping the clutch at least 100 tomes and see if it's better.

 

Yeah, like Joeywhat said, try pumping the clutch all the way through nice and steady. when i replaced my clutch line. i pumped it 150 times before i began to feel some resistance in the clutch. i was at around 350 times pumped before I dared drive it.

 

Oh I've done that, plus done the vacuum pump fluid bleeding method. It's been driven for going on two weeks and probably close to 1,000 miles so I have a hard time thinking that's it. It's going to the shop next week to have the hard brake line I jacked up fixed, so I might have them take a look then too.

 

Could it be that the old brake fluid absorbed a bunch of moisture over the years, and was more compressible compared to brand new fluid? That would explain the feeling of a more instant engagement/disengagement of the clutch.

That feeling of having to be +/-200 rpm is how my car feels like. It's hard to drive it smooth. I have to concentrate on matching the RPM precisely. I drove my buddy's GT the other day. He has the standard 3.31 gears. It felt a lot more forgiving during up/downshifts as well.

 

That's where I was going too, though I have 3.31s so I don't see that difference!