SMF clutch slipping

[firehawk]

Two years ago and only about 10k miles or so, I did the smf conversion when my dmf died. Bought a Luk from Oreiley, as they carried it at the time. Now they don't, and my clutch is already slipping. I have not towed more than 8k lbs, and it started slipping while accelerating up hills, and now it is to the point to slipping while unloaded giving it too much throttle.

I have heard only good things about Luk, but it makes me wonder if they were bought out and/or outsourced. My next clutch will likely be a southbend, as I have used them on my cars without issue.

So far, I have only removed the bottom clutch cover, and I can see the ridges of the clutch, so it is not worn, and there is no oil leaks. It really makes me wonder. I would be curious to hear from other users of Luk smf clutches.

 

[dmaxjoe]

My Luk pressure plate came apart and destroyed my bellhousing. But until then it worked fine for about 15,000 miles.

 

[oregon96psd]

Is your master or slave hanging up causing it to not engage all the way?

 

[6.9poweredscout]

I've never heard of anything bad with luk stuff. I like my sbc, but recently had issues when I tried ordering idi stuff.

 

[firehawk]

Is your master or slave hanging up causing it to not engage all the way?

Pedal comes all the way up and has no free play. I can pull the slave and see if the fork moves. It worth a double check, and I will be working on it later today or tomorrow when I swap the t-stat.

 

[6.9poweredscout]

Should definately have free play

 

[rjglenn]

Did you clean and lube the pilot shaft housing where the throwout bearing rides? I had this problem before and it was because the throwout bearing was binding on the shaft and not fully releasing from the pressure plate, causing an otherwise good clutch to slip.

 

[firehawk]

Should definately have free play

Maybe I am missing something. I replaced the clutch when the dmf failed. The clutch was not slipping, but the flywheel was making noise and was obviously bad when I removed it. At that time, the clutch pedal did not have free play, as in a dead spot with no resistance when it was all the way up. I do not remember seeing an adjustment for clutch engagement like my cars have, but was working fine before the clutch swap and for nearly two years after. I'll pull the slave and see if the fork moves. If it does, that is a problem.

 

[6.9poweredscout]

maybe something happened causing something to stick?

 

[madpogue]

I'll pull the slave and see if the fork moves. If it does, that is a problem.

You could also try disconnecting the pushrod eyelet from the stud, and see if that allows the hydraulics to back off further.

 

[firehawk]

Slave looks fine, disengages clutch, and when engaged, springs look fully compressed. Tranny will come out, and will go from there.

 

[RLDSL]

Problem is not all these kits are exactly the same thickness as the factory setup and shims have a habit of getting left out behind flywheels . Napa sells an adjustable pushrod for about 11 bucks for your clutch to set it properly when changing to a non stock assembly
You should have roughly 1" free play at the top of the pedal and the clutch should begin to engage roughly 1" off the floor. Set to these specs and your clutch parts will last.
Since you have the starter cutout switch on your clutch rod , you will need to remove the plastic housing and grind a relief in it so the nut on the adjustable rod will fit into it, then push it all back through the firewall from the engine side attached to the master.

 

[firehawk]

Problem is not all these kits are exactly the same thickness as the factory setup and shims have a habit of getting left out behind flywheels . Napa sells an adjustable pushrod for about 11 bucks for your clutch to set it properly when changing to a non stock assembly
You should have roughly 1" free play at the top of the pedal and the clutch should begin to engage roughly 1" off the floor. Set to these specs and your clutch parts will last.
Since you have the starter cutout switch on your clutch rod , you will need to remove the plastic housing and grind a relief in it so the nut on the adjustable rod will fit into it, then push it all back through the firewall from the engine side attached to the master.

That is some good info. I would much rather give that a try than pull the tranny and buy a new clutch kit.