[doolyd]

So after reading a couple of threads on another forum apparently the LUK Clutch Kits are suspect due to the plastic throw out bearing. I think Jerry had an email to them inquiring about this change but I wanted to know if anyone has has any issues with them.

I need to replace my clutch (really my TOB) but I am going to do everything and just wanted to get feedback.

I found a different post for on a Suburban/Truck forum about the same issue but I was looking for confirmation.

"I've always used luk in the past with no problems to date...the last kit I bought a couple months ago for my '86 2wd with 4.3L and 3sp (same clutch setup as 465 though...12"..she lasted 145,000mi!!), and the throwout bearing had a "plastic" sleeve, but the area of contact with the pressure plate and the innards were still steel. I called them up to ask, like you, WTF, they said in testing the composite (not really plastic) sleeve held up better in testing, with less fork wear, then the steel version..I installed it, no problems so far, she's my daily driver, about 10,000mi on it thus far..holding up well...I wouldn't worry about it...the composites they have today are very well engineered.."

 

[doolyd]

Nobody has recently put in a new clutch with the plastic throw-out bearing sleeve?

 

[doolyd]

Went to the dealer and they have an OE kit with an all metal throw-out bearing so it looks like I will go that route. NOBODY USE LUK any more.

 

[K.wag]

That is a little premature as some engineered composites DO have more strength than steel and last longer. Just like I am sure people said the same about synthetic winch lines. I would want some proof of testing that shows they don't before I would discredit them.

 

[Jerry Bransford]

The Luk throwout bearing is not plastic as some think/claim it is. It has some non-metallic content now but not in areas where steel would contribute any needed strength. Just like shocks have plastic content, their urethane bushings, not everything needs to be made from 100% steel.

 

[TJ4Jim]

Replaced my clutch with a new LUK 2 weeks ago and did not see any plastic.

 

[gfiber]

Just received a new Luk clutch Kit Wednesday October 1, 2014 from Parts Geek and the throwout / clutch release bearing has some plastic / composite where the bearing rides on the front bearing retainer. I am in process of gathering up all the parts for a new clutch install. I expected to get a full metal clutch release bearing, hope this one holds up. Anybody know where to get a good one made of all metal?

 

[Jerry Bransford]

None of the plastic in the Luk TOB is structural. The clutch friction material isn't steel either.

 

[Water Dog]

None of the plastic in the Luk TOB is structural. The clutch friction material isn't steel either.

^^^This...! I have used Luk clutches in at least three clutch jobs this past year, and all are holding up fine. The structural parts are encased in steel (the release arm pressure points), and the bearing itself is steel. The composite make up of the bearing sleeve that rides on the transmission bearing retainer is a non wear item and no issue. Here's a picture of the Luk on the right compared to an Autozone on the left.

 

[dmartin1189]

luk clutch kit

I am on my second Luk clutch kit with the 50% plastic throwout bearings. the first failed at less than 2,500 miles and the second failed at 40,000 miles. The dealer has 100% metal throwout bearings. So the question would be about heat transfer in a 100% metal throwout vs a 50% plastic bearing. As the bearing lives on the front of the tranny it can get rid of built up heat threw a metal type bearing, wereas the plastic ones retains it. That is the only reasoning I can come up with. All my other vehicles go 100,000 miles plus with metal style throwout bearings. Makes you wonder if they wanna sell replacement clutch kits more often by making a "wearout' part!!
99 jeep TJ
95 Dodge Ram 1500
99 Jeep XJ

 

[Water Dog]

I am on my second Luk clutch kit with the 50% plastic throwout bearings. the first failed at less than 2,500 miles and the second failed at 40,000 miles. The dealer has 100% metal throwout bearings. So the question would be about heat transfer in a 100% metal throwout vs a 50% plastic bearing. As the bearing lives on the front of the tranny it can get rid of built up heat threw a metal type bearing, wereas the plastic ones retains it. That is the only reasoning I can come up with. All my other vehicles go 100,000 miles plus with metal style throwout bearings. Makes you wonder if they wanna sell replacement clutch kits more often by making a "wearout' part!!
99 jeep TJ
95 Dodge Ram 1500
99 Jeep XJ

You are the only one that I've heard of that has had a low mileage LUK failure (apparently actually two)...kind of makes me wonder if there is something else contributing to it or if it was the install rather than the bearing.

A lot of us have run LUK's for 100's of thousands of miles with no issues.

There is virtually no heat transfer through either type of bearing from the transmission as the bearing sleeve is not a tight fit on the transmission bearing retainer, and the only time the throw out bearing spins is when you have your foot on the clutch.

 

[kjmccarx]

I just got my LuK 091 clutch and it too has a plastic thow-out bearing. I was considering going to Jeep and buying an OE bearing, but I think I'll see how the plastic one holds up. Like many people have said, steel isn't always better. And just because MOPAR uses steel doesn't mean they're right.

I'll be pretty pissed if it gives out in 2,500mi because that will be in the middle of me heading back to school in AZ from the holidays in Oregon.

Here's the bearing included with my 091 clutch kit. Along with a long plastic rod thing whose purpose is currently unknown to me... But I'll find out when I take my old clutch out.

 

[Water Dog]

I just got my LuK 091 clutch and it too has a plastic thow-out bearing. I was considering going to Jeep and buying an OE bearing, but I think I'll see how the plastic one holds up. Like many people have said, steel isn't always better. And just because MOPAR uses steel doesn't mean they're right.

I'll be pretty pissed if it gives out in 2,500mi because that will be in the middle of me heading back to school in AZ from the holidays in Oregon.

Here's the bearing included with my 091 clutch kit. Along with a long plastic rod thing whose purpose is currently unknown to me... But I'll find out when I take my old clutch out.

As mentioned above, the plastic part (actually a composite material) is a completely non wear part. The rod thingee is a clutch alignment tool to center your clutch plate.

 

[kjmccarx]

As mentioned above, the plastic part (actually a composite material) is a completely non wear part. The rod thingee is a clutch alignment tool to center your clutch plate.

Yeah, that's why I'm not worried. Just seems odd that dmartin1189 had two fail fairly soon. But like you said, there could have definitely been other factors at play, or maybe he/she just got unlucky.

 

[piste]

This thread is a bit old, but I wanted to log another unhappy experience with the plastic Luk throwout bearing.
Just about a year ago I put in a new engine, rebuilt the trans and replaced the clutch - including a new flywheel. Then a few weeks ago it starts getting hard to shift and the clutch engagement point is now close to the floor. It gets worse and you can barely shift. After looking inside the clutch housing with my scope, I see what looks like broken metal.
Irritated I pull the trans and find the attached pics. I'm not sure if the side clips loosened first thus the stress and back bracket or the back bracket failed first spreading the clips.

5K miles, under a year and failure.
In all the clutches I have done, I have never had a failure before. Obviously I would not recommend the plastic one.