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Is my brand new clutch slipping??? If not, wtf is going on

8652 Views 12 Replies 8 Participants Last post by  jdbrand
So this is kind of a long story so i will keep it as simple as possible. A few months back my 2011 5.0 started to develop an issue that i thought was the clutch slipping. It was acting strange higher up in the RPM's. It seems to hit a wall higher in the RPM's (like the clutch was letting go) but the RPM's wouldn't jump up, it just seemed to struggle and lose power. I thought with all the computer stuff it was the clutch slipping and the ecu was just trying to correct it in some crazy way. However, about 2 weeks ago I had a new Exedy Mach 5 clutch installed by a reputable speed shop. I got the car back and it seemed fine, of course i was pretty easy on it. Then tonight after some break in, I decided to step on it and see what happen. Well it was good for a second but then when i grabbed second gear it started all over again. So now i'm concerned its not a clutch issue and could be a bigger issue.

The check engine light has never come on and i'm just curious if i glazed the flywheel after the resurface and if not, WTF is going on.
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What kind of milage did you put since the clutch install? I hear at least 300 miles at varying speeds to break it in... last thing you want is a glazed flywheel. a slipping clutch with show you it's slipping when you get on it,usually the rpm jump up, and you're not feeling it you know if they machined your existing flywheel before the new clutch install? If that was my clutch being installed I would def have machined the flywheel... there always is a glaze from the original clutch,leaving that glaze on and having it combine with a different friction material,potentially not compatible with one another can easily alter how a new clutch breaks in...a good level of prep to BOTH clamping surfaces is always the safest route to a great clutch break in.
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The flywheel was turned prior to the clutch install. the break in was a couple hundred before i got on it in anyway. when i did roll on it, I didn't go wide open at first. I took it pretty easy and built the RPM's slow.

The RPM's aren't jumping like i have experienced in previous cars. It just seems to hit a wall around 4000 rpm's and lose a bunch of power then seems to come back to life around 6000 and stays alive till redline.

I don't think its the clutch based on the fact that it dead hooks from a stop and still breaks traction going in to 3rd gear. I just can't imagine what else it could be thats not throwing a code instantly.
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when you do a clutch on these cars you have to take it to the dealer to have the crank relearn done on the computer. your car is pulling timing up top cause something is not right, don't drive the car hard until you do the crank relearn or you might replacing a motor soon
Does this happen with traction control all the way off? If not, Are you sure you're not starting to spin and the car is pulling timing?
Not a clutch issue..... If it isn't flaring up in RPM, it isn't the clutch. A clutch can't cause the car to bog or fail to increase RPM. It's not like it could be grabbing too well.
/\ I agree, sounds like a tune issue. Don't understand why the clutch was the blame to begin with.
The computer is retarding timing to avoid knocking / detonation it sounds like. Our coyote engines run the leanest typically around 3500 - 4500 RPM (stock tune). If you have an aftermarket tune then I would get it checked out as well.

Just get the computer reflashed at your dealer and you should be OK...
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I suspected the tune at first. The clutch wasn't really a suspect, it was just an old issue that i had taken care of.

I just don't understand what changed to make the tune go bad if that is the case. Something mechanical had to happen in order for the car to start pulling timing so bad.
Does this happen with traction control all the way off? If not, Are you sure you're not starting to spin and the car is pulling timing?
Its not breaking traction, it happens when i'm fairly light on the throttle and at speeds that its not really possible to break traction.
Yeah it sounds like the car is pulling timing. Flash it back to stock to see what happens, or try different gas.
Sounds like they didn't reset the CPS properly, and you're confusing the computer.
Well.....So far i'm batting ZERO. I went to the Ford garage and had a CPS relearn done and its still doing the same thing, He actually went through the process twice just to make sure and it didn't work. So then i went home and and got my new tune and loaded it up in the car with the same result. It still seems to be pulling fuel or timing out around the 4000-6000 rpm range. This is puzling me. I'm going to try to reload the race tune tomorrow and see what happens. Then if that fails i'll just try to log and send it off so some on ecan tell me whats going on. I'm starting to think its a mechanical issue but i don't under stand how its not throwing CEL if its pulling that much fuel and timing. It's a very noticable power loss.
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